CN113840556B

CN113840556B - Touch interface for an active footwear system

Info

Publication number: CN113840556B
Application number: CN202080035315.3A
Authority: CN
Inventors: S.H.沃克; P.梅诺
Original assignee: Nike Innovate CV USA
Current assignee: Nike Innovate CV USA
Priority date: 2019-03-14
Filing date: 2020-03-13
Publication date: 2024-02-27
Anticipated expiration: 2040-03-13
Also published as: WO2020186171A1; CN113840556A; EP3937717A1; CN118044673A; EP3937717A4

Abstract

The footwear system may include an interface system for controlling one or more aspects of the footwear. In an example, the interface system may include a touch sensor including two or more electrodes configured to receive user touch input bridging at least two of the electrodes, and the sensor may be configured to receive user touch input at a plurality of locations along a length of the sensor. The measurement circuit may be configured to measure capacitance indication signals from two or more electrodes, and the capacitance indication signals may include information about the location of the user touch input on the sensor.

Description

Touch interface for an active footwear system

Priority claim

The present application claims priority from U.S. patent application Ser. No. 16/353,739, filed on day 14, 3, 2019, which is incorporated herein by reference in its entirety.

Background

Various shoe-based sensors have been proposed to monitor various conditions. For example, brown provides several examples of shoe-based sensors in U.S. patent No.5,929,332, entitled "Sensor shoe for monitoring the condition of a foot". Brown mentions that a foot force sensor may include an insole made of a relatively thin, planar, flexible, resilient dielectric material layer. The foot force sensor may include a conductive interconnect device that may have a resistance that varies based on an applied compressive force.

Brown further discusses shoes worn by diabetics or persons suffering from various foot conditions, and applying excessive pressure to a portion of the foot tends to cause ulcers. The base may include a Force Sensing Resistor (FSR), and a switching circuit coupled with the resistor may activate an alarm unit to alert the wearer to reach or exceed a threshold pressure level.

Devices for automatically tightening articles of footwear have been previously proposed. Liu in U.S. patent No.6,691,433 entitled "Automatic tightening shoe" provides a first fastener that is mounted to the upper portion of the shoe, and a second fastener that is connected to the closure member and is removably engageable with the first fastener to maintain the closure member in a tightened state. Liu teaches a drive unit mounted in the heel portion of the sole. The drive unit includes a housing, a spool rotatably mounted in the housing, a pair of pull wires, and a motor unit. Each wire has a first end connected to the spool and a second end corresponding to a wire aperture in the second fastener. The motor unit is coupled to the bobbin. Liu teaches that the motor unit is operable to drive rotation of the spool in the housing to wind the pull wire on the spool to pull the second fastener toward the first fastener. Liu also teaches a catheter unit through which the pull wire may extend.

Drawings

In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. The same numbers with different letter suffixes may represent different instances of similar components. The accompanying drawings illustrate generally, by way of example and not by way of limitation, various embodiments discussed in the present document.

FIG. 1 generally illustrates an exploded view of components of an article of active footwear according to an example embodiment.

Figures 2A-2C generally illustrate a sensor system and a motorized lacing engine according to some example embodiments.

Fig. 3 generally illustrates a block diagram of components of a motorized lacing system according to an example embodiment.

Fig. 4 is a graphical representation showing pressure distribution data for a nominal or average foot (left) and a high arch foot (right) in an article of footwear when a user of the article of footwear is standing.

Fig. 5A and 5B generally illustrate a representation of a capacitance-based foot presence sensor in an insole of an article of footwear according to an example embodiment.

Fig. 6 generally illustrates a capacitive sensor system for foot presence detection according to an example embodiment.

Fig. 7 generally illustrates a schematic diagram of a first capacitance-based foot presence sensor according to an example embodiment.

Fig. 8 generally illustrates a schematic diagram of a second capacitance-based foot presence sensor according to an example embodiment.

Fig. 9A, 9B, and 9C generally illustrate examples of capacitance-based foot presence sensor electrodes according to some example embodiments.

FIG. 10 shows a flow chart illustrating an example of using foot presence information from a footwear sensor.

FIG. 11 shows a flow chart illustrating a second example of using foot presence information from a footwear sensor.

Fig. 12 generally shows a graph of first time-varying information from a capacitive foot presence sensor.

Fig. 13 generally shows a chart of second time-varying information from a capacitive foot presence sensor.

Fig. 14 generally shows a chart of third time-varying information from a capacitive foot presence sensor.

Fig. 15 generally shows a graph of fourth time-varying information from a capacitive foot presence sensor.

Fig. 16 generally illustrates a graph of time-varying information and signal morphology constraints from a capacitive foot presence sensor according to an example embodiment.

Fig. 17 generally shows an example of a graphical representation of a capacitance-based foot presence sensor in a midsole of an article of footwear and located below a dielectric stack.

Fig. 18 generally illustrates an example including a graph showing the effect of a dielectric filler on a capacitance indicating signal from a capacitive foot presence sensor.

Fig. 19 generally illustrates an example of a graph that shows a portion of a third signal from a capacitance-based foot presence sensor in footwear that indicates capacitance.

Fig. 20 generally shows an example of foot presence signal information over multiple sitting periods.

Fig. 21A-21D generally illustrate examples of different planar electrode configurations.

Fig. 22 generally shows an example of a graph showing a relationship between sensor sensitivity and sensor shape.

Fig. 23 generally illustrates an example of a graph showing the relationship between sensor sensitivity and the type of corrective insert.

Fig. 24 generally shows an example of a graph showing the relationship between sensor response and simulated sweat.

Fig. 25 generally shows an example of a graph showing the relationship between sensor response and simulated sweat in the case of an average signal.

Fig. 26 generally shows an example of a state diagram of the sweat compensation method.

Fig. 27 generally shows an example of a graph showing foot presence sensor data.

Fig. 28A and 28B generally illustrate an example diagram of a footbed assembly with a rear seat cover.

29A-29D generally illustrate an example of a footbed assembly having a first hook and loop cover for a lacing engine.

30A-30D generally illustrate an example of a footbed assembly having a second hook and loop cover for a lacing engine.

Fig. 31 generally illustrates an example of a footwear system state machine.

Fig. 32 generally illustrates a chart showing values of foot presence sensor signals over time and including a footwear donning event.

Fig. 33 generally shows a graph that shows the values of the second foot presence sensor signal over time and includes ground effects.

Fig. 34 generally shows a scatter plot showing the relationship between wear duration and foot presence sensor signal amplitude.

Fig. 35 generally shows a perspective view of a housing structure with a capacitive interface.

Fig. 36 generally shows a side view of a housing structure with a capacitive interface.

Fig. 37 generally shows an example of a relationship between the position of the input body and the capacitance signal.

Fig. 38 generally shows an example of a relationship between the position of the input body and the spool position.

FIG. 39 generally illustrates an example of a relationship between an input gesture and a spool position.

Detailed Description

Concept of self-tightening shoelaces first the imaginary power laces worn by the movie (return to future II) that was shown in 1989 by Ma Di microphone fley (mark McFly)Sports shoes are widely used. Although->At least one power tie athletic shoe has been released that has an appearance similar to a motion picture prop version in coming back to future II, but employs an internal mechanical system and wrap aroundFootwear platforms are not necessarily adapted for mass production or daily use. Furthermore, previous designs of motorized lacing systems have relatively suffered from problems such as high manufacturing costs, complexity, assembly challenges, lack of applicability, and weak or fragile mechanical mechanisms, to name just a few. The present inventors have developed a modular footwear platform to accommodate motorized and non-motorized lacing engines, which addresses some or all of the problems discussed above, and the like. The components discussed below provide various benefits including, but not limited to, serviceable components, interchangeable automated lacing engines, robust mechanical designs, robust control algorithms, reliable operation, simplified assembly processes, and retail level customization. Various other advantages of the components described below will be apparent to those skilled in the relevant arts.

In an example, a modular automatic lacing footwear platform includes a midsole secured to a midsole in an article of footwear for receiving a midsole of a lacing engine. The midsole plate is designed such that the lacing engine may be added to the footwear platform at the time of purchase. The midsole panel, as well as other aspects of the modular automated footwear platform, allow for the interchangeable use of different types of lacing engines. For example, the motorized lacing engine discussed below may be replaced with a human lacing engine. Alternatively, a fully automated motorized lacing engine with foot presence sensing or other features may be housed within a standard mid-floor.

The automated footwear platforms discussed herein may include outsole actuator interfaces to provide tightening control as well as visual feedback to the end user, for example, using LED illumination projected through the translucent protective outsole material. The actuators may provide tactile and visual feedback to the user to indicate the status of the lacing engine or other automated footwear platform component.

In an example, the footwear platform includes a foot presence sensor for detecting when a foot is present in the shoe. When the foot is detected, one or more footwear functions or processes may be initiated, e.g., automatically, without further user input or commands. For example, the control circuit may automatically initiate lace tightening, data collection, footwear diagnostics, or other processes when it is detected that the foot is properly seated in the footwear against the insole.

Activation or activation of the automatic lacing or footwear tightening mechanism prematurely can affect the user's experience with the footwear. For example, if the lacing engine is started before the foot is fully seated against the insole, it may be difficult for the user to put the remainder of his or her foot into the footwear, or the user may have to manually adjust the lacing tension. The inventors have therefore recognized that the problem to be solved includes determining whether the foot is properly or fully seated in the article of footwear, such as the toes, midsole, and heel portions being properly aligned with corresponding portions of the insole. The inventors have further recognized that problems include using as few sensors as possible to accurately determine foot position or foot orientation, e.g., reducing sensor costs and assembly costs, as well as reducing equipment complexity.

Solutions to these problems include providing sensors in the arch and/or heel area of the footwear. In an example, the sensor is a capacitive sensor configured to sense a change in a nearby electric field. As the foot enters or leaves the footwear, a change in electric field or a change in capacitance may be achieved, including certain portions of the foot being farther from the sensor than other portions of the foot. In an example, the capacitive sensor is integrated with or housed within the lacing engine housing. In an example, at least a portion of the capacitive sensor is disposed outside of the lacing engine housing and includes one or more conductive interconnects to power or processing circuitry inside the housing.

Capacitive sensors suitable for foot presence detection may have a variety of configurations. The capacitive sensor may comprise a plate capacitor, wherein one plate is configured to move relative to the other, for example in response to pressure or pressure changes applied to one or more plates. In an example, the capacitive sensor includes a plurality of traces, e.g., arranged substantially in a plane parallel or coincident with the upper surface of the insole. Such traces may be laterally separated by an air gap (or other material such as styrofoam) and may be selectively or periodically driven by an AC drive signal provided by an excitation circuit. In an example, the electrodes may have a staggered, vanity configuration. Such capacitive sensors may provide a varying capacitance signal based on movement of the electrodes themselves relative to each other, and based on interference of an electric field in the vicinity of the electrodes due to the presence or absence or movement of a foot or other object.

In an example, the capacitance-based sensor may be more reliable than a mechanical sensor, for example, because the capacitance-based sensor need not include moving parts. The surface of the capacitance-based sensor may be coated or covered with a durable, electric field-permeable material so that the electrodes may be protected from direct exposure to environmental changes, humidity, spills, dirt or other contaminants, and human or other materials do not directly contact the electrodes of the sensor.

In an example, a capacitive sensor provides an analog output signal detected by the sensor that is indicative of the magnitude of the capacitance or indicative of a change in the capacitance. The output signal may have a first value (e.g., corresponding to a low capacitance) when the foot is present near the sensor, and a second, different value (e.g., corresponding to a high capacitance) when the foot is not present.

In an example, the output signal may provide further information when a foot is present. For example, there may be a detectable change in the capacitance signal associated with a step event. Furthermore, there may be a detectable long-term drift in the capacitance signal that may be indicative of wear and/or remaining life of a shoe component (e.g., insole, orthosis, or other component).

In an example, a capacitive sensor includes or is coupled to a capacitive digitizer circuit configured to provide a digital signal indicative of an amplitude of capacitance sensed by the sensor. In an example, the capacitive sensor includes a processor circuit configured to provide an interrupt signal or logic signal that indicates whether the sensed capacitance value meets a specified threshold capacitance condition. In an example, the capacitive sensor measures a capacitive characteristic relative to a baseline or reference capacitance value, and the baseline or reference may be updated or adjusted to accommodate environmental changes or other changes that may affect the sensed capacitance value.

In an example, the capacitive sensor is disposed under the foot near the arch or heel area of the insole of the shoe. The capacitive sensor may be substantially planar or flat. The capacitive sensor may be rigid or flexible and configured to follow the contour of the foot. In some cases, an air gap (e.g., which may have a relatively low dielectric constant or low relative permittivity) may exist between a portion of the capacitive sensor and the foot when the shoe is worn. A gap filler (e.g., having a relatively high dielectric constant greater than air or a greater relative permittivity) may be provided over the capacitive sensor to bridge any airspace between the capacitive sensor and the foot surface. The gap filler may be compressible or incompressible. In an example, the gap filler is selected to provide a suitable compromise between dielectric value and suitability for use in footwear in order to provide a sensor with sufficient sensitivity and user comfort under the foot.

Various components of the automated footwear platform are discussed below, including the motorized lacing engine, foot presence sensors, midsole board, and various other components of the platform. While much of this disclosure focuses on foot presence sensing as a trigger for a motorized lacing engine, many aspects of the design discussed are applicable to human lacing engines, or other circuits or features that may interact with the foot presence sensor, for example, to automate other footwear functions, such as data collection or physiological monitoring. The term "automated", as used in, for example, "automated footwear platforms," is not intended to encompass systems that operate without specified user input only. Rather, the term "automated footwear platform" may include various electric and manual, automatic and manual activation, lacing or retaining systems for tightening footwear, or mechanisms for controlling other aspects of active footwear.

FIG. 1 generally illustrates an exploded view of components of an article of active footwear according to an example embodiment. The example of fig. 1 includes a motorized lacing system 100 having a lacing engine 110, a cover 120, an actuator 130, a midsole 140, a midsole 155, and an outsole 165. The lacing engine 110 may include user exchangeable components in the system 100, and may include or may be coupled to one or more foot presence sensors. In an example, the lacing engine 110 includes or is coupled to a capacitive foot presence sensor. The capacitive foot presence sensor, not shown in the example of fig. 1, may include a plurality of electrodes disposed on the foot-facing side of the lacing engine 110. In an example, the electrodes of the capacitive foot presence sensor may be housed within the lacing engine 110, may be integrated with the housing of the lacing engine 110, or may be disposed elsewhere in the vicinity of the lacing engine 110 and coupled to the internal power or processing circuitry of the lacing engine 110 using one or more electrical conductors.

Assembly of motorized lacing system 100 in the example of fig. 1 begins with securing midsole plate 140 within midsole 155. Next, the actuator 130 may be inserted into an opening on the outside of the midsole plate 140, e.g., opposite the interface button embedded in the outsole 165. Next, the lacing engine 110 may be inserted into the midsole panel 140. In an example, lacing engine 110 may be coupled with one or more sensors disposed elsewhere in the footwear. Other assembly methods may be similarly performed to construct motorized lacing system 100.

In an example, lacing system 100 is inserted under a continuous loop of lacing wire and the lacing wire is aligned with a spool in lacing engine 110. To complete the assembly, the cover 120 may be inserted into a midsole plate 140 securing device in the midsole plate 140, secured in a closed position, and latched in a recess in the midsole plate 140. The cover 120 may capture the lacing engine 110 and may help maintain alignment of the lacing wires during operation.

The midsole panel 140 includes a lacing engine cavity 141, medial and lateral lacing guides 142, a front flange 143, a rear flange 144, upper (top) and lower (bottom) surfaces, and an actuator cutout 145. The lacing engine cavity 141 is configured to receive the lacing engine 110. In this example, the lacing engine cavity 141 holds the lacing engine 110 in the lateral and anterior/posterior directions, but does not include features that lock the lacing engine 110 in the cavity 141. Optionally, the lacing engine cavity 141 includes detents, protrusions, or other mechanical features along one or more sidewalls to forcibly retain the lacing engine 110 within the lacing engine cavity 141.

The lacing guides 142 may help guide the lacing wire into position with the lacing engine 110. The lacing guides 142 may include chamfered edges and lower beveled surfaces to help guide the lacing wire to a desired position relative to the lacing engine 110. In this example, lace guide 142 includes an opening in the side of midsole plate 140 that is many times wider than a typical lacing wire diameter, although other dimensions may be used.

In the example of fig. 1, midsole plate 140 includes an engraved or contoured front flange 143 that further extends on the inside of midsole plate 140. The example front flange 143 is designed to provide additional support under the arch of the footwear platform. However, in other examples, the front flange 143 may be less visible on the inside. In this example, the rear flange 144 includes a profile having an extension on both the inboard and outboard sides. The illustrated rear flange 144 may provide enhanced outboard stability to the lacing engine 110.

In an example, one or more electrodes may be embedded in midsole plate 140 or disposed on midsole plate 140, and may form part of a foot presence sensor, such as a capacitive foot presence sensor. In an example, lacing engine 110 includes sensor circuitry electrically coupled to one or more electrodes on midsole board 140. The sensor circuit may be configured to use the electric field or capacitance information sensed from the electrodes to determine whether a foot is present in an area adjacent to midsole plate 140. In an example, the electrode extends from a forward-most edge of the front flange 143 to a rearward-most edge of the rear flange 144, and in other examples, the electrode extends over only a portion of one or more of the flanges.

In an example, the footwear or motorized lacing system 100 includes an interface with one or more sensors that may monitor or determine the presence of a foot in the footwear, the absence of a foot in the footwear, or a foot position characteristic within the footwear. Based on information from one or more such foot presence sensors, footwear including motorized lacing system 100 may be configured to perform a variety of functions. For example, the foot presence sensor may be configured to provide binary information regarding whether the foot is present in the footwear. In an example, a processor circuit coupled to the foot presence sensor receives and interprets digital or analog signal information and provides binary information regarding whether the foot is present in the footwear. If the binary signal from the foot presence sensor indicates the presence of a foot, the lacing engine 110 in the motorized lacing system 100 may be activated, for example, to automatically increase or decrease tension on the lacing wires, or other footwear tightening means, such as tightening or loosening the footwear around the foot. In an example, the lacing engine 110, or other portion of the article of footwear, includes a processor circuit that may receive or come from the foot presence sensor.

In an example, the foot presence sensor may be configured to provide information regarding the location of the foot as it enters the footwear. Motorized lacing system 100 may generally be activated, for example, to tighten a lacing cable, such as against all or a portion of an insole of an article of footwear, only when the foot is properly positioned or seated in the footwear. The foot presence sensor that senses information regarding foot travel or position may provide information regarding whether the foot is fully or partially seated, such as with respect to the insole or with respect to some other feature of the article of footwear. The automatic lacing process may be interrupted or delayed until the information from the sensor indicates that the foot is in the correct position.

In an example, the foot presence sensor may be configured to provide information regarding the relative position of the foot within the interior of the footwear. For example, the foot presence sensor may be configured to sense whether the footwear is "fit" well to a given foot, such as by he determining the relative position of one or more of the arch, heel, toe, or other portions of the foot with respect to a corresponding portion of the footwear configured to receive such foot portions. In an example, the foot presence sensor may be configured to sense whether the position of the foot or foot portion changes over time relative to a designated or previously recorded reference position, for example due to loosening of the lacing wire over time, or due to natural expansion and contraction of the foot itself.

In an example, the a-foot presence sensor may include an electrical, magnetic, thermal, capacitive, pressure, light, or other sensor device that may be configured to sense or receive information regarding the presence of a body. For example, the electrical sensor may comprise an impedance sensor configured to measure an impedance characteristic between at least two electrodes. The electrical sensor may provide a sensor signal having a first value when a body, such as a foot, is located near or adjacent to the electrode, and a second, different value when the body is away from the electrode. For example, a first impedance condition may be associated with an empty footwear condition, while a second, smaller impedance condition may be associated with an occupied footwear condition.

The electrical sensor may include an AC generator circuit and an antenna configured to transmit or receive high frequency signal information, including radio frequency information, for example. Based on the proximity of the body to the antenna, one or more electrical signal characteristics, such as impedance, frequency, or signal amplitude, may be received and analyzed to determine whether the body is present. In an example, a Received Signal Strength Indicator (RSSI) provides information about a power level in a received radio signal. The change in RSSI, e.g., relative to some trace or reference value, may be used to identify the presence or absence of the body. In an example, wiFi frequencies may be used, for example in one or more of the 2.4GHz, 3.6GHz, 4.9GHz, 5GHz, and 5.9GHz bands. In an example, frequencies in the kilohertz range, such as about 400kHz, may be used. In an example, a change in the power signal in the milliwatt or microwatt range may be detected.

The foot presence sensor may comprise a magnetic sensor. The first magnetic sensor may include a magnet and a magnetometer. In an example, the magnetometer may be located in or near the lacing engine 110. The magnets may be remote from the lacing engine 110, such as in an auxiliary sole or insole, configured to be worn over the outsole 165. In an example, the magnet is embedded in the foam of the auxiliary bottom or in another compressible material. When the user presses the auxiliary bottom while standing or walking, a change in the position of the magnet relative to the magnetometer can be sensed and reported via the sensor signal.

The second magnetic sensor may include a magnetic field sensor configured to sense a change or interruption in the magnetic field (e.g., via hall effect). When the body is close to the second magnetic sensor, the sensor may generate a signal indicative of a change in the surrounding magnetic field. For example, the second magnetic sensor may include a hall effect sensor that changes the voltage output signal in response to a detected change in the magnetic field. The voltage change at the output signal may be due to a voltage difference being created across the electrical signal conductors, such as a magnetic field transverse to the current in the conductors and perpendicular to the current.

In an example, the second magnetic sensor is configured to receive electromagnetic field signals from the body. For example, varshavsky et al, in U.S. Pat. No.8,752,200 entitled "Devices, systems and methods for security using magnetic field based identification," teach authentication using a unique electromagnetic signature of a human body. In an example, a magnetic sensor in an article of footwear may be used to authenticate or verify that the current user is the owner of the shoe via a detected electromagnetic signature, and that the article should be automatically laced, e.g., according to one or more specified lacing preferences (e.g., tightness) of the owner.

In an example, the foot presence sensor includes a thermal sensor configured to sense a temperature change in or near a portion of the footwear. When the wearer's foot enters the article of footwear, the internal temperature of the article may change when the body temperature of the wearer himself differs from the environment of the article of footwear. Thus, the temperature sensor may provide an indication of the possible presence or absence of the foot based on the temperature change.

In an example, the foot presence sensor includes a capacitive sensor configured to sense a change in capacitance. The capacitive sensor may comprise a single plate or electrode, or the capacitive sensor may comprise a multi-plate or multi-electrode configuration. Various examples of capacitive foot presence sensors are further described herein.

In an example, the foot presence sensor includes a light sensor. The light sensor may be configured to determine whether the line of sight is interrupted, for example, between opposite sides of the footwear cavity. In an example, the light sensor includes a light sensor that is covered by the foot when the foot is inserted into the footwear. An indication of foot presence or position may be provided when the sensor indicates a change in sensed light or brightness conditions.

Any of the different types of foot presence sensors discussed herein may be used independently, or information from two or more different sensors or sensor types may be used together to provide information regarding the presence, absence, orientation, fit to footwear, or other information regarding the foot and/or its relationship to footwear.

Figures 2A-2C generally illustrate a sensor system and a motorized lacing engine according to some example embodiments. Fig. 2A illustrates various external features of the example lacing engine 110, including the shell structure 150, the shell screw 108, the lacing channel 112 (also referred to as the lacing guide relief 112), the lacing channel transition 114, the spool recess 115, the button opening 122, the button 121, the button membrane seal 124, the programming head 128, the spool 131, and the lacing grooves 132 in the spool 131. Other designs may be similarly used. For example, other types of switches may be used, such as a sealed dome switch, or the membrane seal 124 may be eliminated, and so forth. In an example, the lacing engine 110 may include one or more interconnects or electrical contacts to interface circuitry internal to the lacing engine 110 with circuitry external to the lacing engine 110, such as an external foot presence sensor (or component thereof), an external actuator (such as a switch or button), or other device or component.

The lacing engine 110 may be held together by one or more screws, such as the shell screws 108. The cabinet screw 108 may be located adjacent to the main drive mechanism to enhance the structural integrity of the lacing engine 110. The cabinet screws 108 also serve to assist in the assembly process, such as ultrasonic welding to hold the enclosure structure 150 together for external welds.

In the example of fig. 2A, lacing engine 110 includes lacing channels 112, lacing channels 112 receiving lacing or lacing cables once the engine is assembled in an automated footwear platform. The lacing channel 112 may include channel walls with chamfered edges to provide a smooth guide surface against which the lacing wire may run during operation. A portion of the smooth guiding surface of the lace channel 112 may include a channel transition 114, which may be a widened portion of the lace channel 112 that leads into the spool recess 115. The spool recess 115 transitions from the channel transition 114 to a generally circular portion that closely follows the contour of the spool 131. The spool recess 115 can help retain the lacing wire wound on the spool, as well as help maintain the position of the spool 131. Other aspects of the design may hold other means of spool 131. In the example of fig. 2A, spool 131 is shaped like one half of a yo-yo ball, with lacing grooves 132 passing through the flat top surface of a spool shaft (not shown in fig. 2A) extending downward from the opposite side.

The exterior side of lacing engine 110 includes a button opening 122 that receives button 121, button 121 may be configured to activate or adjust one or more features of the automated footwear platform. The button 121 may provide an external interface for activating various switches contained in the lacing engine 110. In some examples, the housing structure 150 includes a button membrane seal 124 to provide waterproof and dust protection. In this example, the button membrane seal 124 is a transparent plastic (or similar material) up to a few mils (thousandths of an inch) thick that may adhere from the upper surface of the housing structure 150, for example, on the foot or under the outside. In another example, the button film seal 124 is an approximately 2 mil thick vinyl adhesive backing film that covers the button 121 and button opening 122. Other types of buttons and sealants may be similarly used.

Fig. 2B is an illustration of a housing structure 150 that includes a top 102 and a bottom 104. In this example, the top 102 includes features such as a cabinet screw 108, a lacing channel 112, a lacing channel transition 114, a spool recess 115, a button opening 122, and a button seal recess 126. In an example, the button seal recess 126 is part of the top 102 that is released to provide for insertion of the button membrane seal 124.

In the example of fig. 2B, the bottom 104 includes features such as a wireless charger access 105, a connector 106, and a grease isolation wall 109. Also shown, but not identified, are various features of the housing screw base for receiving the housing screw 108, and the portion of the grease isolation wall 109 for retaining the drive mechanism. The grease isolation wall 109 is designed to retain grease or similar compounds around the drive mechanism away from the various electrical components of the lacing engine 110.

The housing structure 150 may include one or more electrodes 170 embedded in or applied to the structural surface in one or both of the top 102 and bottom 104. In the example of fig. 2B, electrode 170 is shown coupled to bottom 104. In an example, the electrode 170 includes a portion of a capacitance-based foot presence sensor circuit (e.g., see the foot presence sensor 310 discussed herein). Additionally or alternatively, the electrode 170 may be coupled to the top 102. The electrode 70 coupled to the top 102 or bottom 104 may be used for wireless power transfer and/or as part of a capacitance-based foot presence sensor circuit. In an example, the electrode 170 includes one or more portions disposed on an outer surface of the housing structure 150, and in another example, the electrode 170 includes one or more portions disposed on an inner surface of the housing structure 150.

Fig. 2C is a diagram of various internal components of the lacing engine 110 according to an example embodiment. In this example, lacing engine 110 further includes bobbin magnet 136, O-ring seal 138, worm drive 140, bushing 141, worm drive key, gear box 148, gear motor 145, motor encoder 146, motor circuit board 147, worm gear 151, circuit board 160, motor head 161, battery connection 162, and wired charging head 163. Spool magnet 136 helps track the motion of spool 131 through detection by a magnetometer (not shown in fig. 2C). The O-ring seal 138 serves to seal dust and moisture in the lacing engine 110 that may migrate around the spool shaft. The circuit board 160 may include one or more interfaces or interconnections for foot presence sensors, such as capacitive foot presence sensor 310 discussed below. In an example, the circuit board 160 includes one or more traces or conductive plates that provide a portion of the footpresence sensor 310.

In this example, the primary drive components of the lacing engine 110 include a worm drive 140, a worm gear 151, a gear motor 145, and a gear box 148. The worm gear 151 is designed to inhibit back drive of the worm drive 140 and gear motor 145, which means that the primary input force transmitted from the lacing wire via the spool 131 can be split over the relatively large worm gear and worm drive teeth. This arrangement protects gear box 148 from the need to include gears of sufficient strength to withstand dynamic loads from active use of the footwear platform or tightening loads from the tightening lacing system. The worm drive 140 includes additional features to help protect various fragile portions of the drive system, such as the worm drive key. In this example, the worm drive key is a radial slot in the motor end of the worm drive 140 that interfaces with the pin through a drive shaft out of the gearbox 148. This arrangement prevents the worm drive 140 from exerting undue axial forces on the gearbox 148 or gear motor 145 by allowing the worm drive 140 to move freely in an axial direction (away from the gearbox 148), transferring these axial loads to the bushing 141 and the housing structure 150.

Fig. 3 generally illustrates a block diagram of components of a motorized lacing system 300 according to an example embodiment. The system 300 includes the following components of a motorized lacing system, but not necessarily all, such as a housing structure 150 including an interface button 301, a capacitive foot presence sensor 310, and an enclosed printed circuit board assembly (PCA) having a processor circuit 320, a battery 321, a charging coil 322, an encoder 325, a motion sensor 324, and a drive mechanism 340. The drive mechanism 340 includes a motor 341, a transmission 342, a lace spool 343, and the like. The motion sensor 324 may include a single or multi-axis accelerometer, magnetometer, gyroscope, or other sensor or device configured to sense movement of the housing structure 150 (or movement of one or more components within the housing structure 150 or coupled to the housing structure 150), and so forth.

In the example of fig. 3, the processor circuit 320 is in data or power signal communication with one or more of the interface button 301, the foot presence sensor 310, the battery 321, the charging coil 322, and the drive mechanism 340. A transmission 342 couples the motor 341 to the spool 343 to form the drive mechanism 340. In the example of fig. 3, the button 301, foot presence sensor 310, and environmental sensor 350 are shown as being external, in part or in part, to the housing structure 150.

In alternative embodiments, one or more of the button 301, foot presence sensor 310, and environmental sensor 350 may be enclosed in the housing structure 150. In an example, the foot presence sensor 310 is disposed inside the housing structure 150 to protect the sensor from perspiration and dirt or debris. Minimizing or eliminating the connection through the walls of the housing structure 150 helps to improve the durability and reliability of the assembly.

In an example, the processor circuit 320 controls one or more aspects of the drive mechanism 340. For example, the processor circuit 320 may be configured to receive information from the buttons 301 and/or from the foot presence sensor 310 and/or from the motion sensor 324, and in response, control the drive mechanism 340, for example, to tighten or loosen footwear about the foot. In an example, the processor circuit 320 is additionally or alternatively configured to issue commands from the foot presence sensor 310 or other sensors to obtain or record sensor information, as well as other functions. In an example, the processor circuit 320 adjusts operation of the drive mechanism 340 in accordance with one or more of detecting the presence of a foot using the foot presence sensor 310, detecting the orientation or position of a foot using the foot presence sensor 310, or detecting a specified gesture using the motion sensor 324.

In an example, the system 300 includes an environmental sensor 350. Information from the environmental sensor 350 may be used to update or adjust a baseline or reference value of the foot presence sensor 310. As explained further below, the capacitance value measured by the capacitive foot presence sensor may change over time, for example, in response to an environmental condition in the vicinity of the sensor. Using information from the environmental sensor 350, the processor circuit 320 and/or the foot presence sensor 310 may thus be configured to update or adjust the measured or sensed capacitance value.

In an example, under various conditions, the foot presence sensor 310 may be disabled or signals from the foot presence sensor 310 may be ignored by the processor circuit 320. For example, if the drive mechanism 340 is activated and actively spooled or unwound, the processor circuit 320 may be configured to ignore interrupts or other signals from the foot presence sensor 310. In an example, if the footwear is being charged, for example using charging coil 322 or wired charging head 163, processor circuit 320 may be configured to ignore interrupts or other signals from foot presence sensor 310.

Fig. 4 is a graphical representation showing pressure distribution data for a nominal or average foot (left) and a high arch foot (right) in an article of footwear 400 when a user of the article of footwear is standing. In this example, it can be seen that areas of relatively greater underfoot pressure are included at the heel area 401, at the ball area 402 (e.g., between the arch and the toes), and at the hallux area 403 (e.g., the "big toe" area). However, as noted above, it may be advantageous to include various active components (e.g., including foot presence sensor 310) in the concentrated area, such as at or near the arch area. In an example, in the arch region, the shell structure 150 is generally less visible or noticeable to a user when wearing an article of footwear that includes the shell structure 150.

In the example of fig. 4, the lacing engine cavity 141 may be disposed in the arch region. One or more electrodes corresponding to foot presence sensor 310 may be located at or near first location 405. The capacitance value measured using the electrode located at the first location 405 may vary depending on the proximity of the foot relative to the first location 405. For example, the average foot and the high arch foot will achieve different capacitance values because the surface of the foot itself is a different distance from the first location 405. In an example, the position of the foot presence sensor 310 and/or the lacing engine 110 may be adjusted (e.g., by a user or a point-of-sale technician) relative to the footwear, such as to accommodate different foot characteristics of different users, and to enhance the signal quality obtained from the foot presence sensor 310. In an example, the sensitivity of the foot presence sensor 310 may be adjusted, for example, by increasing the drive signal level or changing the dielectric material between the foot presence sensor 310 and the foot.

Fig. 5A and 5B generally illustrate a representation of a capacitance-based foot presence sensor in an insole of an article of footwear according to an example embodiment. The capacitance-based foot presence sensor may be disposed below the surface of the subject or body 550 (e.g., the foot) when wearing the article containing the sensor.

In fig. 5A, a capacitance-based foot presence sensor may include a first electrode assembly 501A coupled to a capacitance sensing controller circuit 502. In an example, the controller circuit 502 is included in the processor circuit 320 or includes functions performed by the processor circuit 320. In the example of fig. 5A, the first electrode assembly 501A and/or the controller circuit 502 may be included in or mounted to an interior portion of the housing structure 150, or may be coupled to a PCA inside the housing structure 150. In an example, the first electrode assembly 501A may be disposed at or near a foot-facing surface of the housing structure 150. In an example, the first electrode assembly 501A includes a plurality of traces distributed across an interior, upper surface area of the housing structure 150.

In fig. 5B, the capacitance-based foot presence sensor may include a second electrode assembly 501B coupled to a capacitance sensing controller circuit 502. The second electrode assembly 501B may be mounted to or near an exterior portion of the housing structure 150 and may be electrically coupled to a PCA inside the housing structure 150, for example using a flexible connector 511. In an example, the second electrode assembly 501B may be disposed at or near a foot-facing surface of the housing structure 150. In an example, the second electrode assembly 501B includes a flexible circuit that is secured to an inner or outer surface of the housing structure 150 and is coupled to the processor circuit 320 via one or more conductors.

In an example, the controller circuit 502 includes an Atmel ATSAML21E18B-MU, ST Microelectronics STM32L476M, or other similar device. The controller circuit 502 may be configured to provide an AC drive signal to at least one pair of electrodes in the first electrode assembly 501A or the second electrode assembly 501B, and in response, sense a change in the electric field based on a corresponding change in the proximity of the subject or body 550 to the pair of electrodes, and so forth, as explained in more detail below. In an example, the controller circuit 502 includes or uses the foot presence sensor 310 or the processor circuit 320.

Various materials may be disposed between the electrode assembly 501 and the object or body 550 to be sensed. For example, an electrode insulator, material of the housing structure 150, insole material, insert material 510, sock or other sleeve, body strap, ergonomic strap, or other material may be interposed between the body 550 and the electrode assembly 501, e.g., to alter the dielectric properties of footwear, thereby affecting the capacitive detection sensitivity of a sensor incorporating or using the electrode assembly 501. The controller circuit 502 may be configured to update or adjust the excitation or sensing parameters based on the amount or type of interposed material, for example, to enhance the sensitivity or signal-to-noise ratio of the capacitance values sensed using the electrode assembly 501.

In the example of fig. 5A/B, the first electrode assembly 501A/second electrode assembly 501B may be energized by a signal generator in the controller circuit 502 so that an electric field may be projected from the top, foot-facing side of the electrode assembly. In an example, the electric field under the electrode assembly may be blocked at least in part using a driven shield located under the sense electrode. The driving shield and the electrode assembly may be electrically insulated from each other. For example, if the first electrode assembly 501A is on one surface of the PCA, the drive shield may be on the bottom layer of the PCA, or on any of a plurality of inner layers on a multi-layer PCA. In an example, the driven shield may have an equal or greater surface area than the first electrode assembly 501A and may be centered directly under the first electrode assembly 501A.

The drive shield may receive a drive signal and, in response, generate an electric field. The field generated by the driven shield may have substantially the same polarity, phase, and/or amplitude as the field generated by the first electrode assembly 501A. The field driving the shield may repel the electric field of the first electrode assembly 501A, isolating the sensor field from various parasitic effects, such as undesired coupling to the ground plane of the PCA. The field generated by the driven shield may help to detect specific areas directly and in focus, may help to reduce environmental impact, and may help to reduce parasitic capacitance effects. In an example, a drive shield is included and can help reduce the effects of temperature changes on the sensor assembly. Temperature affects parasitic offset characteristics, for example, temperature variations can cause parasitic ground plane capacitance to vary. The use of a shield, for example interposed between the sensor electrode and ground, may help mitigate the effects of parasitic ground plane capacitance from the sensor measurements.

The driven shield may similarly be configured for use with the second electrode assembly 501B. For example, the second electrode assembly 501B may be disposed above or near the housing structure 150, such as shown in the example of fig. 5B. In an example, a portion of the housing structure 150 may include or may be partially covered with a conductive film that serves as a drive shield. Additionally or alternatively, when the second electrode assembly 501B is disposed at a location other than at or near the top of the housing structure 15, the drive shield may be disposed elsewhere in the article of footwear.

The preferred location for housing structure 150 is in the arch region of the footwear, as this is a region that is less likely to be felt by the wearer and less likely to cause discomfort to the wearer. One advantage of using capacitive sensing to detect the presence of a foot in a shoe includes that the capacitive sensor works properly even when the capacitive-like sensor is placed in the arch area and the user's arch is relatively or abnormally high. For example, the sensor drive signal amplitude or morphology characteristics may be changed or selected based on the signal-to-noise ratio of the detected signal received from the capacitive sensor. In an example, the sensor drive signal may be updated or adjusted each time the footwear is used, for example, to accommodate changes in one or more materials (e.g., socks, insoles, etc.) disposed between the first electrode assembly 501A or the second electrode assembly 501B and the body 550.

In an example, an electrode assembly of a capacitive sensor, such as first electrode assembly 501A or second electrode assembly 501B, may be configured to sense differences in signals between multiple electrodes, such as between electrodes oriented in the X and Y axes. In an example, a suitable sampling frequency may be between about 2 and 50 Hz. In some examples, capacitance-based foot sensing techniques may be relatively invariant to perspiration (moisture) in the sock on the insole or around the foot. The effect of such moisture can reduce the dynamic range of detection because the presence of moisture can increase the measured capacitance. However, in some examples, the dynamic range is sufficient to accommodate such effects within the moisture level in the footwear.

Fig. 6 generally illustrates a capacitive sensor system 600 for foot presence detection according to an example embodiment. The system 600 includes a body 550 (e.g., representing a foot in or near an article of active footwear) and a first electrode 601 and a second electrode 602. Electrodes 601 and 602 may form all or a portion of the example first electrode assembly 501A or second electrode assembly 501B of fig. 5A/B, including, for example, a portion of foot presence sensor 310. In the example of fig. 6, the first electrode 601 and the second electrode 602 are shown vertically spaced from each other and from the body 550, however, the electrodes may similarly be horizontally spaced, for example, as detailed in the examples of fig. 7-9C. That is, in an example, the electrodes may be disposed in a plane parallel to the lower surface of the body 550. In the example of fig. 6, the first electrode 601 is configured as a transmitting electrode and is coupled to a signal generator 610. In an example, the signal generator 610 includes a portion of the processor circuit 320 of the example of fig. 3. That is, the processor circuit 320 may be configured to generate and apply a driving signal to the first electrode 601.

Since the first electrode 601 is excited by the driving signal from the signal generator 610, an electric field 615 may be generated mainly between the first electrode 601 and the second electrode 602. That is, various components of the generated electric field 615 may extend between the first electrode 601 and the second electrode 602, and edge components of the generated electric field 615 may extend in other directions. For example, the edge component may extend from the transmitter electrode or first electrode 601 away from the housing structure 150 (not depicted in the example of fig. 6) and terminate back at the receiver electrode or second electrode 602.

Information about the electric field 615, including information about changes in the electric field 615 due to the proximity of the body 550, may be received or sensed by the second electrode 602. The signals sensed from the second electrode 602 may be processed using various circuits and used to provide analog or digital signals indicative of the presence or absence of the body 550.

For example, the strength of the electric field 615 may be received by the second electrode 602 and measured using a sigma-delta analog-to-digital converter circuit (ADC) 620 configured to convert the analog capacitance indication signal to a digital signal. When an object such as body 550 invades electric field 615, including its edge components, the electrical environment near the electrodes changes. When the body 550 enters the field, a portion of the electric field 615 is shunted to ground rather than being received and terminated at the second electrode 602, or passed through the body 550 (e.g., rather than through air) before being received at the second electrode 602. This may result in a change in capacitance that may be detected by the foot presence sensor 310 and/or by the processor circuit 320.

In an example, the second electrode 602 may receive the electric field information substantially continuously and the information may be sampled continuously or periodically by the ADC 620. Information from ADC 620 may be processed or updated according to offset 621 and may then provide digital output signal 622. In an example, offset 621 is a capacitive offset (e.g., internal to processor circuit 320) that may be specified or programmed, or another capacitor that may be based on environmental changes that track other variable characteristics of time, temperature, and environment.

In an example, the digital output signal 622 may include binary information regarding whether the body 550 is present, such as by comparing a measured capacitance value to a specified threshold. In an example, the digital output signal 622 includes quantitative information about the measured capacitance, such as may be used (e.g., by the processor circuit 320) to provide an indication of the likelihood of the presence or absence of the body 550.

Periodically, or whenever the foot presence sensor 310 is inactive (e.g., as determined using information from the motion sensor 324), the capacitance value may be measured and stored as a reference value, a baseline value, or an environmental value. As the foot or body approaches the foot presence sensor 310 and the first and second electrodes 601, 602, the measured capacitance may decrease or increase, for example, relative to a stored reference value. In an example, one or more threshold capacitance levels may be stored, for example in an on-chip register with the processor circuit 320. When the measured capacitance exceeds a specified threshold, then body 550 may be determined to be present (not present) in the footwear containing foot presence sensor 310.

Foot presence sensor 310, and electrodes 601 and 602 that form part of foot presence sensor 310, may take a variety of different forms, as shown in the following several non-limiting examples. In an example, the foot presence sensor 310 is configured to sense or use information about the mutual capacitance between multiple electrodes or plates.

In an example, electrodes 601 and 602 are arranged in an electrode grid. Capacitive sensors using grids may include variable capacitors at the intersections of each row and each column of the grid. Optionally, the electrode grid comprises electrodes arranged in a plurality of rows or columns. A voltage signal may be applied to the rows or columns and the body or foot near the surface of the sensor may affect the local electric field, thereby reducing the mutual capacitance effect. In an example, the capacitance change at multiple points on the grid may be measured to determine the body position, for example by measuring the voltage in each axis. In an example, mutual capacitance measurement techniques may provide information from multiple locations around the grid at the same time.

In an example, mutual capacitance measurement uses an orthogonal grid of transmit and receive electrodes. In such grid-based sensor systems, a measurement value for each of a plurality of discrete X-Y coordinate pairs may be detected. In an example, capacitance information from multiple capacitors may be used to determine foot presence or foot orientation in the footwear. In another example, capacitance information from one or more capacitors may be acquired over time and analyzed to determine foot presence or foot orientation. In an example, rate of change information regarding X and/or Y detection coordinates may be used to determine when the foot is properly or fully seated relative to an insole in the footwear.

In an example, a self-capacitance based foot presence sensor may have the same X-Y grid as a mutual capacitance sensor, but the columns and rows may operate independently. In self-capacitance sensors, the capacitive load of the body at each row or column can be detected independently.

Fig. 7 generally illustrates a schematic diagram of a first capacitance-based foot presence sensor according to an example embodiment. In the example of fig. 7, the first capacitive sensor 700 includes a plurality of parallel capacitive plates. A plurality of plates may be disposed on or in the housing structure 150, for example, at or near the underside of the foot when the article of footwear including the first capacitive sensor 700 is worn. In an example, the capacitive foot presence sensor 310 includes or uses a first capacitive sensor 700.

In the example of fig. 7, four conductive capacitor plates are shown as 701-704. The plate may be made of a conductive material such as a conductive foil. The foil may be flexible and may optionally be embedded in the plastic of the housing structure 150 itself or may be independent of the housing structure 150. It should be appreciated that any conductive material may be used, such as films, inks, deposited metals, or other materials. In the example of fig. 7, plates 701-704 are arranged in a common plane and spaced apart from one another to form discrete conductive elements or electrodes.

The capacitance value of a capacitor is functionally related to the dielectric constant of the material between the two plates forming the capacitor. Within first capacitive sensor 700, a capacitor may be formed between each pair of two or more capacitor plates 701-704. Thus, as shown in FIG. 7, six effective capacitors are formed by six unique pairs of capacitor plates 701-704 as capacitors A, B, C, D, E and F. Alternatively, two or more plates may be electrically coupled to form a single plate. That is, in an example, the capacitor may be formed using: first and second capacitor plates 701 and 702 electrically coupled to provide a first conductor, and third and fourth capacitor plates 703 and 704 electrically coupled to provide a second conductor.

In an example, the capacitive effect between the first capacitor plate 701 and the second capacitor plate 702 is represented in fig. 7 by the dashed line capacitor identified by the letter a. The capacitive effect between first capacitor plate 701 and third capacitor plate 703 is represented by the dashed line capacitor identified by letter B. The capacitive effect between the first capacitor plate 702 and the fourth capacitor plate 704 is represented by the dashed line capacitor identified by the letter C, and so on. Those of ordinary skill in the art will appreciate that each dashed capacitor represents an electrostatic field extending between a respective pair of capacitor plates. Hereinafter, for ease of identification, the capacitors formed by each pair of capacitive plates are denoted by the letters (e.g., "a", "B", etc.) used in fig. 7 to identify the dashed capacitors.

For each pair of capacitor plates in the example of fig. 7, the effective dielectric between the plates includes an air gap (or other material) disposed between the plates. For each pair of capacitor plates, any portion of the body or foot adjacent to the corresponding pair of capacitor plates may be part of the effective dielectric of a given pair of capacitor plates, or may affect the effective dielectric. That is, a variable dielectric may be provided between each pair of capacitor plates depending on the proximity of the body to the corresponding pair of plates. For example, the closer the body or foot is to a given pair of plates, the greater the value of the effective dielectric will be. As the dielectric constant value increases, the capacitance value increases. Such a change in capacitance value may be received by the processor circuit 320 and used to indicate whether an object is present at or near the first capacitive sensor 700.

In the example of foot presence sensor 310 including first capacitive sensor 700, a plurality of capacitive sensor drive/monitor circuits may be coupled to plates 701-704. For example, separate drive/monitor circuits may be associated with each pair of capacitor plates in the example of fig. 7. In an example, the drive/monitor circuit may provide a drive signal (e.g., a time-varying excitation signal) to the pair of capacitor plates, and in response, may receive a value indicative of the capacitance. Each drive/monitor circuit may be configured to measure a variable capacitance value of an associated capacitor (e.g., capacitor "a" corresponds to first plate 710 and second plate 702), and may be further configured to provide a signal indicative of the measured capacitance value. The drive/monitor circuit may have any suitable structure for measuring capacitance. In an example, two or more drive/monitor circuits may be used together, for example to provide an indication of the difference between capacitance values measured using different capacitors.

Fig. 8 generally illustrates a schematic diagram of a second capacitance-based foot presence sensor according to an example embodiment. The example of fig. 8 includes a second capacitive sensor 800 that includes a first electrode 801 and a second electrode 802. The foot presence sensor 310 may include or use a second capacitive sensor 800. In the example of fig. 8, the first electrode 801 and the second electrode 802 are arranged along a substantially planar surface, for example in a comb configuration. In an example, the drive circuitry (e.g., processor circuitry 320) may be configured to generate excitation or stimulation signals to apply to the first electrode 801 and the second electrode 802. The same or different circuitry may be configured to sense a response signal indicative of a change in capacitance between the first electrode 801 and the second electrode 802. The capacitance may be affected by the presence relative to the body or foot. For example, first electrode 801 and second electrode 802 may be disposed on or near a surface of shell structure 150, such as near the foot when the foot is present within footwear including shell structure 150.

In an example, the second capacitive sensor 800 includes an etched conductive layer, for example in an X-Y grid, to form a pattern of electrodes. Additionally or alternatively, the electrodes of the second capacitive sensor 800 may be provided by etching a plurality of separate, parallel layers of a plurality of conductive materials, for example, forming a grid with vertical lines or traces. In this or other capacitive sensors, no direct contact is required between the body or foot and the conductive layer or electrode. For example, the conductive layer or electrode may be embedded in the housing structure 150, or may be coated with a protective or insulating layer. Alternatively, the body or foot to be detected may interface with or affect the electric field characteristics in the vicinity of the electrodes, and a change in the electric field may be detected.

In an example, separate capacitance values may be measured for the first electrode 801 relative to ground or reference and measured for the second electrode 802 relative to ground or reference. The signal for foot presence detection may be based on the difference between the individual capacitance values measured for the first electrode 801 and the second electrode 802. That is, the foot presence or foot detection signal may be based on the difference between the discrete capacitance signals measured using the first electrode 801 and the second electrode 802.

Fig. 9A and 9B generally illustrate examples of a third capacitive sensor 900 according to some examples. Fig. 9C generally illustrates an example of a fourth capacitive sensor 902. Fig. 9A shows a schematic top view of a third capacitive sensor 900. Fig. 9B shows a perspective view of a sensor assembly 901 comprising a third capacitive sensor 900. Fig. 9C shows a schematic top view of a fourth capacitive sensor 902.

In the example of fig. 9A, the third capacitive sensor 900 includes an electrode region having a first electrode trace 911 and a second electrode trace 912. The first electrode trace 911 and the second electrode trace 912 are separated by an insulator trace 913. In an example, the first electrode trace 911 and the second electrode trace 912 may be copper, carbon, silver, and other conductive materials, and may be disposed on a substrate made of FR4, polyimide, PET, and other materials. The substrate and traces of the third capacitive sensor 900 may include one or more flexible portions.

The first electrode trace 911 and the second electrode trace 912 may be substantially distributed across the surface area of the third capacitive sensor 900. When third capacitive sensor 900 is installed, the electrode traces may be positioned against an upper or top surface of housing structure 150. In an example, one or both of the first electrode trace 911 and the second electrode trace 912 may be about 2mm wide. The insulator traces 913 may have approximately the same width. In an example, the trace width may be selected based on the footwear size or insole type, etc. For example, different trace widths may be selected for the first electrode trace 911 and the second electrode trace 912 and/or for the insulator trace 913, e.g., depending on the distance between the trace and the body to be sensed, the insole material, the gap filler, the housing structure 150 material, or other materials used in footwear, e.g., to minimize the signal-to-noise ratio of the capacitance values measured using the third capacitive sensor 900.

The third capacitive sensor 900 may include a connector 915. The connector 915 may be coupled with a mating connector, such as to a PCA in the housing structure 150. The mating connector may include one or more conductors to electrically couple the first electrode trace 911 and the second electrode trace 912 with the processor circuit 320.

In an example, third capacitive sensor 900 includes input signal conductors 920A and 920B. Input signal conductors 920A and 920B may be configured to couple with one or more input devices, such as dome buttons or other switches, for example, corresponding to buttons 121 in the example of fig. 2A.

Fig. 9B shows a sensor assembly 901 comprising a third capacitive sensor 900, buttons 121A and 121B, and membrane seals 124A and 124B. In an example, the corresponding conductive surfaces of input signal conductors 920A and 920B are coupled with buttons 121A and 121B. Membrane seals 124A and 124B are adhered to buttons 121A and 121B, for example, to protect buttons 121A and 121B from debris images and to keep them aligned with the conductor surfaces.

In the example of fig. 9C, the fourth capacitive sensor 902 includes an electrode region having a first electrode trace 921 and a second electrode trace 922. The first electrode trace 921 and the second electrode trace 922 are separated by an insulator trace 923. The electrode traces may comprise various conductive materials, and the fourth capacitive sensor 902 may comprise one or more flexible portions. The fourth capacitive sensor 902 may include a connector 925 and may be coupled with a mating connector, such as to a PCA in the housing structure 150.

The inventors have recognized that the problem to be solved includes obtaining a suitable sensitivity or response of the capacitive foot presence sensor, for example, when all or part of the foot sensor is spaced apart from the foot or body to be detected, for example by an air gap or other intervening material. The inventors have recognized that a solution may include using a plurality of electrodes of specific shape, size, and orientation to enhance the orientation and relative strength of the electric field generated by the electrodes when energized. That is, the inventors have determined the optimal electrode configuration for capacitive foot presence sensing.

In an example, the plurality of electrodes of the fourth capacitive sensor 902 includes a first electrode trace 921 and a second electrode trace 922, and each of the first electrode trace 921 and the second electrode trace 922 includes discrete fingers or traces extending substantially parallel to each other. For example, the first electrode trace 921 and the second electrode trace 922 may include a plurality of staggered conductive finger portions, as shown in fig. 9C.

In an example, the second electrode trace 922 may include a shoreline or perimeter portion that extends substantially around an outer perimeter edge or surface portion of the fourth capacitive sensor 902 and substantially around the first electrode trace 921. In the example of fig. 9C, the shoreline including the second electrode trace 922 extends around substantially all of the top surface of the fourth capacitive sensor 902 assembly, however, in some other examples, the shoreline may extend around a lesser portion of the sensor. The inventors further recognized that when most or all of the fingers of the first electrode trace 921 and the second electrode trace 922 are arranged substantially parallel to each other, an optimal electric field is generated for detecting the presence of a foot, e.g., rather than including one or more traces or finger portions that are not parallel. For example, in contrast to the fourth capacitive sensor 902, the third capacitive sensor 900 of fig. 9A includes non-parallel fingers, such as vertically extending finger portions at an upper portion of the first electrode trace 911 and horizontally extending finger portions at a lower portion of the first electrode trace 911. The relative thicknesses of the first electrode trace 921 and the second electrode trace 922 may be adjusted to further enhance the sensitivity of the sensor. In an example, the second electrode trace 922 is three or more times thicker than the first electrode trace 921.

In an example, the capacitance values measured by foot presence sensor 310, for example using one or more of first, second, third, and fourth capacitance sensors 700, 800, 900, and 902, may be provided to a controller or processor circuit, such as processor circuit 320 of fig. 3. In response to the measured capacitance, the processor circuit 320 may actuate the drive mechanism 340, for example, to adjust the footwear tension around the foot. The adjustment operations may alternatively be performed at least in part by discrete "hard-wired" components, by a processor executing software, or by a combination of hard-wired components and software. In an example, actuating the drive mechanism 340 includes (1) monitoring a signal from the foot presence sensor 310 using one or more drive/monitoring circuits, for example using the processor circuit 320, (2) determining which (if any) received capacitance signal indicates a capacitance value that meets or exceeds a specified threshold (e.g., is stored in a memory register of the processor circuit 320 and/or in a memory circuit in data communication with the processor circuit 320), (3) characterizing a position, size, orientation, or other characteristic of the body or foot in proximity to the foot presence sensor 310, for example based on various specified thresholds being exceeded, and (4) allowing, enabling, adjusting, or inhibiting actuation of the drive mechanism 340 according to the characterization.

Fig. 10 shows a flow chart illustrating an example of a method 1000 that includes using foot presence information from footwear sensors. At operation 1010, an example includes receiving foot presence information from the foot presence sensor 310. The foot presence information may include binary information regarding whether a foot is present in the footwear (see, e.g., the interrupt signals discussed in the examples of fig. 12-14), or may include an indication of a likelihood that a foot is present in the article of footwear. The information may include electrical signals provided from foot sensor 310 to processor circuit 320. In an example, the foot presence information includes quantitative information regarding a position of the foot relative to one or more sensors in the footwear.

At operation 1020, an example includes determining whether the foot is fully seated in the footwear. If the sensor signal indicates that the foot is fully seated, the example may continue to operation 1030 to actuate the drive mechanism 340. For example, when the foot is determined to be fully seated at operation 1020, the drive mechanism 340 may be engaged via the spool 131 to tighten the footwear lace, such as based on information from the foot presence sensor 310, as described above. If the sensor signal indicates that the foot is not fully seated, the example may continue at operation 1022 by delaying or idling for some specified interval (e.g., 1-2 seconds, or more). After a specified delay, the example may return to operation 1010 and the processor circuit may resample the information from the foot presence sensor 310 to determine if the foot is fully seated.

After actuating the drive mechanism 340 at operation 1030, the processor circuit 320 may be configured to monitor the foot position information at operation 1040. For example, the processor circuit may be configured to periodically or intermittently monitor information from the foot presence sensor 310 regarding the absolute or relative position of the foot in the footwear. In an example, monitoring the foot position information at operation 1040 and receiving the foot presence information at operation 1010 may include receiving information from the same or different foot presence sensors 310. For example, different electrodes may be used to monitor foot presence or position information at operations 1010 and 1040.

At operation 1040, an example includes monitoring information from one or more buttons (e.g., button 121) associated with footwear. Based on information from button 121, actuation mechanism 340 may be instructed to loosen or loosen the lace, for example, when the user wishes to remove the footwear.

In an example, lace tension information may additionally or alternatively be monitored, or used as feedback information for actuating the drive mechanism 340 or for tensioning the lace. For example, lace tension information may be monitored by measuring a driving current provided to motor 341. The tension may be characterized by a manufacturing point or may be preset or adjusted by a user and may be associated with a monitored or measured drive current level.

At operation 1050, examples include determining whether the foot position has changed in the footwear. If the foot presence sensor 310 and the processor circuit 320 do not detect a change in foot position, the example may continue to delay at operation 1052. After the specified delay interval at operation 1052, the example may return to operation 1040 to resample the information from the foot presence sensor 310 to again determine if the foot position has changed. The delay at operation 1052 may be in the range of milliseconds to several seconds and may optionally be specified by the user.

In an example, the delay at operation 1052 may be automatically determined by the processor circuit 320, for example, in response to footwear usage characteristics. For example, if the processor circuit 320 determines that the wearer is engaged in strenuous exercise (e.g., running, jumping, etc.), the processor circuit 320 may reduce the delay duration provided at operation 1052. If the processor circuit determines that the wearer is engaged in non-strenuous activities (e.g., walking or sitting), the processor circuit may increase the delay duration provided at operation 1052. By increasing the delay duration, battery life may be conserved by deferring sensor sampling events and corresponding power consumption by the processor circuit 320 and/or the foot presence sensor 310. In an example, if a change in position is detected at operation 1050, the example may continue by returning to operation 1030, for example, to actuate the drive mechanism 340 to tighten or loosen the footwear about the foot. In an example, the processor circuit 320 includes or incorporates a hysteresis controller for the drive mechanism 340 to help avoid an unnecessary lace spool in the event that, for example, a small change in foot position is detected.

FIG. 11 shows a flow chart illustrating an example of an example 1100 of using foot presence information from a footwear sensor. In an example, the example of fig. 11 may be implemented with the operation of a finger state machine, for example, using the processor circuit 320 and the foot presence sensor 310.

State 1110 may include a "transport" state that represents a default or baseline state of an active article of footwear that includes one or more features that may be affected by information from foot presence sensor 310. In the shipping state 1110, various movable components of the footwear may be turned off or disabled to preserve the battery life of the footwear.

In response to the "power on" time 1115, the example may transition to the "disabled" or inactive state 1120. The drive mechanism 340, or other feature of the active footwear, may remain in standby in the disabled state 1120. Various inputs may be used to trigger a time to exit the disabled state 1120. For example, user input from one of the buttons 121 may be used to indicate a transition out of the disabled state 1120. In an example, information from the motion sensor 324 may be used as a wake-up signal. The information from the motion sensor 324 may include information regarding the movement of the footwear, such as corresponding to the user placing the footwear in a ready position, or the user may insert a foot into the footwear.

The state machine may remain in the disabled state 1120 after the power-on time 1115 until an automatic lacing enable event 1123 is encountered or received. The automatic strap enable event 1123 may be triggered manually by a user (e.g., using user input or an interface device of the drive mechanism 340) or may be triggered automatically, e.g., in response to gesture information received from the motion sensor 324. After the automatic lacing activation event 1123, a calibration event 1125 may occur. Calibration event 1125 may include setting a reference or baseline value for the capacitance of foot presence sensor 310, for example, to account for environmental impact on the sensor. Calibration may be based on information sensed by the foot presence sensor 310 itself, or may be based on programmed or specified reference information. Calibration may be deferred, for example, if the calibration results are outside of a specified range or the environmental impact is excessive.

After the automatic lacing enable event 1123, the state machine may enter a hold state 1130 to "wait for foot present signal". In state 1130, the state machine may wait for an interrupt signal from the foot presence sensor 310 and/or from the motion sensor 324. When an interrupt signal is received, for example, indicating that a foot is present, or indicating a sufficient likelihood of a foot being present, the event register may indicate "find foot" at event 1135.

When a find foot event 1135 occurs, the state machine may transition to initiate various functions. For example, the footwear may be configured to tighten or adjust the tension characteristics using the drive mechanism 340 in response to finding the foot event 1135. In an example, the processor circuit 320 actuates the drive mechanism 340 to adjust the lace tension by an initial amount in response to finding the foot event 1135, and the processor circuit 320 delays further tensioning of the footwear unless or until a further control gesture is detected or a user input is received. That is, the state machine may transition to the "wait for move" state 1140. In an example, processor circuit 320 enables drive mechanism 340 but does not actuate the drive mechanism after footer event 1135 is found. In state 1140, the state machine may maintain or pause the additional sensed footwear movement information prior to initiating any initial or further tension adjustments. After waiting for movement state 1140, a stomping/walking/standing event 1145 may be detected, and in response, processor circuit 320 may further adjust the tension characteristics of the footwear.

The stomping/walking/standing event 1145 may include various discrete, sensed inputs, such as from one or more sensors in the active footwear. For example, a stomping event may include information from motion sensor 324 indicating positive acceleration (e.g., in a specified or general direction) as well as an "up" or "upright" orientation. In an example, a stomping event includes a "knee up" or kicking type event, in which the user lifts one knee substantially vertically and forward. Acceleration characteristics from the motion sensor 324 may be analyzed, for example, to determine whether the acceleration meets or exceeds a specified threshold. For example, a slow knee-raising event may not trigger a stomping event response, while a fast or quick knee-raising event may trigger a stomping event response.

The walking event may include information from the motion sensor 324 indicating a positive walking pattern and an "up" or "upright" orientation. In an example, the motion sensor 324 and/or the processor circuit 320 are configured to identify a walking event, which may be identified when a walking event is identified and when an accelerometer (e.g., included in the motion sensor 324 or separate from the motion sensor 324) indicates that the footwear is upright.

A standing event may include information from a motion sensor that indicates an upper "or" upright "orientation, e.g., no further information from the motion sensor regarding acceleration or directional changes of the footwear. In an example, information about changes in the capacitance signal from the capacitive foot presence sensor 310 may be used to discern standing events, as described further below. That is, the capacitance signal from foot presence sensor 310 may include a change in signal that may indicate whether the user is standing, such as when the user's foot applies downward pressure to the footwear.

The specific example of a stomping/walking/standing event 1145 should not be considered limiting, and various other gestures, time-based inputs, or user input controls may be provided to further control or affect the behavior of the footwear, such as after the foot is detected at the find foot event 1135.

After a stomp/walk/stand event 1145, the state machine may include a "wait to unbuckle" state 1150. Waiting for the unbuckled state 1150 may include monitoring user input and/or gesture information (e.g., using the motion sensor 324) to indicate that the footwear is to be loosened, untied, untwisted, or unbuckled. In the wait for unbuckled state 1150, a state manager, such as the processor circuit 320, may indicate that the lacing engine or drive mechanism 340 is unbuckled and should return to the wait for foot presence signal state 1130. That is, in a first example, an unbuckled event 1155 may occur (e.g., in response to user input), the state machine may transition the footwear to an unbuckled state, and the state machine may return to the wait for foot presence signal state 1130. In a second example, an automatic lacing disable event 1153 may occur and transition the footwear to a disabled state 1120.

In an example, other gesture information may be sensed and, in response, various actions may be initiated. The gesture input may be identified with respect to conventional wear or use patterns. For example, a specified gesture trigger may be used, e.g., a particular sequence or number of gestures may be included to "wake up" the processor circuit 320 and indicate that a responsive action is required. For example, in footwear incorporating motion sensor 324, the gesture sequence of "pause-double click-pause" may itself be a command, or may be used to wake up the system and indicate that another gesture instruction is to be followed. In an example, a double-click input, such as double-clicking the toe of one foot from the heel of the other foot, may be sufficient to indicate a response. For example, a double click input may be used to trigger to unlatch the lace or to unwind the lace from a spool to loosen the article of footwear.

Fig. 12 generally illustrates a graph 1200 of first time-varying information from a capacitive foot presence sensor. The example of fig. 12 includes a graph of capacitance versus time and a first time-varying capacitance signal 1201 plotted on the graph. In an example, the first time-varying capacitance signal 1201 may be obtained using the foot presence sensor 310 described herein. The first time-varying capacitance signal 1201 may correspond to a measured capacitance between a plurality of electrodes in the foot presence sensor 310, or an indication of the body's effect on the electric field, as described above. In an example, the first time-varying capacitance signal 1201 represents an absolute or relative capacitance signal value, and in another example, the signal represents a difference between the signal value and a reference signal value.

In an example, the first capacitance signal 1201 may be compared to a particular first threshold capacitance value 1211. Foot presence sensor 310 may be configured to compare or processor circuit 320 may be configured to receive capacitive information from foot presence sensor 310 and to compare. In the example of fig. 12, the first threshold capacitance value 1211 is represented as a constant non-zero value. The foot presence sensor 310 and/or the processor circuit 320 may provide the first interrupt signal INT1 when the first capacitance signal 1201 meets or exceeds the first threshold capacitance value 1211, such as at time T1. The first interrupt signal INT1 may remain high enough as long as the capacitance value indicated by the foot presence sensor 310 meets or exceeds the first threshold capacitance value 1211.

In an example, the first interrupt signal INT1 may be used in the example of fig. 10, for example, at operation 1010 or 1020. At operation 1010, receiving foot presence information from the foot presence sensor 310 may include receiving a first interrupt signal INT1, such as at the processor circuit 320. In an example, operation 1020 may include using the interrupt signal information to determine whether the foot or the likelihood of being fully seated in the footwear. For example, the processor circuit 320 may monitor the duration of the first interrupt signal INT1 to determine how long the foot presence sensor 310 provides a capacitance value that exceeds the first threshold capacitance value 1211. If the duration exceeds the specified reference duration, the processor circuit 320 may determine that the foot is fully seated or may be fully seated.

In an example, the first interrupt signal INT1 may be used in the example of fig. 11, for example at state 1130 or event 1135. In state 1130, the state machine may be configured to wait for an interrupt signal, such as INT1, from the processor circuit 320 or from the foot presence sensor 310. At time 1135, the state machine may receive the first interrupt signal INT1 and, in response, may initiate one or more subsequent states.

In an example, the first threshold capacitance value 1211 is adjustable. The threshold may change based on a change in the measured or detected capacitance baseline or reference, for example due to environmental changes. In an example, the first threshold capacitance value 1211 may be specified by a user. The user's designation of a threshold value may affect the sensitivity of the footwear. In an example, the first threshold capacitance value 1211 may be automatically adjusted in response to a sensed environmental or material change in or around the foot presence sensor 310.

Fig. 13 generally shows a chart 1300 of second time-varying information from a capacitive foot presence sensor. The example of fig. 13 illustrates how fluctuations in the second capacitance signal 1202 around the first threshold capacitance value 1211 may be processed or used to determine more information about the presence or orientation of a foot in the footwear.

In an example, the second capacitance signal 1202 is received from the foot presence sensor 310 and the second capacitance signal 1202 is compared to the first threshold capacitance value 1211. Other thresholds may similarly be used depending on the user, user preferences, type of footwear, or environment or environmental characteristics, etc. In the example of fig. 13, the second capacitance signal 1202 may intersect the first threshold capacitance value 1211 at times T2, T3, and T4. In an example, multiple threshold crossings may be used to positively identify foot presence by the foot presence sensor 310, for example by indicating a travel path of the foot upon entering the footwear. For example, the time interval defined by the intersection of the first and second thresholds at times T2 and T3 may indicate the duration of time that the toe or phalange of the foot is at or near the electrode of the foot presence sensor 310. When the sensed capacitance is less than the first threshold capacitance value 1211, the interval between T3 and T4 may correspond to the time at which the metatarsal joint or metatarsal of the foot traveled on or near the electrode of the foot presence sensor 310. When the phalanges enter the footwear, the metatarsal joints and bones may be spaced a greater distance from the foot presence sensor 310 than the phalanges to the foot presence sensor 310, and thus the resulting capacitance between measured T3 and T4 may be smaller. At time T4, the heel or talus of the foot may be slid into place and the arch may be seated on the electrode of foot presence sensor 310, causing the sensed capacitance to recover and exceed first threshold capacitance value 1211. Accordingly, the foot presence sensor 310 or the processor circuit 320 may be configured to present the second interrupt signal INT2 between time T2 and T3, and the third interrupt signal INT3 after time T4.

In an example, the processor circuit 320 may be configured to positively identify the presence of a foot based on the sequence of interrupt signals. For example, the processor circuit 320 may use information regarding received interrupt signals and regarding one or more intervals or durations between received interrupt signals. For example, the processor may be configured to look for a pair of interrupt signals separated by a specified duration to provide a positive indication of the presence of the foot. For example, in fig. 13, the duration between T3 and T4 may be used to provide an indication of the presence of the foot, e.g., with some adjustable or specified error range. In an example, the processor circuit 320 may receive the interrupt signal as data and process the data with other user input signals, e.g., as part of gesture-based user input. In an example, information regarding whether an interrupt signal is present may be used to verify or ignore one or more other signals. For example, the accelerometer signal may be verified and processed by the processor circuit 320 when an interrupt signal is received or recently received, or the processor circuit 320 may ignore the accelerometer signal when there is no interrupt signal corresponding to a foot presence sensor.

The examples of fig. 12 and 13 illustrate embodiments in which the measured capacitance value from the foot presence sensor 310 is reliably constant or reproducible over time, including where there is a change in environmental conditions. However, in many footwear applications, environmental capacitance changes in embedded electronics may occur constantly or unpredictably, such as due to changes in temperature, humidity, or other environmental factors. Significant changes in ambient capacitance can adversely affect the activation of the foot presence sensor 310, such as by changing the baseline or reference capacitance characteristics of the sensor.

Fig. 14 generally shows a chart 1400 of third time-varying information from a capacitive foot presence sensor. The example of fig. 14 shows how reference capacitance changes are considered, such as changes due to various environmental conditions, changes in usage scenarios, or changes due to wear or degradation of footwear components. Examples include a third capacitance signal 1203 plotted on graph 1400 having a second threshold capacitance 1212 and a reference capacitance 1213 that varies over time. In the example of fig. 14, the reference capacitance 1213, which varies with time, increases with time. In other examples, the reference capacitance may decrease over time or may fluctuate, such as during an footwear usage event (e.g., during a course of a day, a game played, a user's settings or preferences, etc.). In an example, the reference capacitance may vary over the life of various components of the footwear itself, such as an insole, outsole, insole, orthotic insert, or other component of the footwear.

In an example, the third capacitance signal 1203 is received from the foot presence sensor 310 and the third capacitance signal 1203 is compared to the second threshold capacitance 1212, for example using processing circuitry on the foot presence sensor 310 or using the processor circuitry 320. In examples where the time-varying reference capacitance 1213 is not considered or used, a threshold crossing of the third capacitance signal 1203 may be observed at times T5, T6, and T8. However, the second threshold capacitance 1212 may be adjusted, for example, using sensed information from the foot presence sensor 310 in real time. The adjustment of the second threshold capacitance 1212 may be based on a reference capacitance 1213 that varies over time.

In an example, the second threshold capacitance 1212 is continuously adjusted, and the amount of adjustment corresponds to a change in the reference capacitance 1213 over time. In an alternative example, the second threshold capacitance 1212 is adjusted in stepwise increments, for example in response to a specified threshold amount of change in the reference capacitance 1213 over time. The stepwise adjustment technique is illustrated in fig. 14 by a stepwise increase in the second threshold capacitance 1212 with the illustrated spacing. For example, the second threshold capacitance 1212 increases at times T7 and T10 in response to a specified threshold increase Δc in capacitance in the time-varying reference capacitance 1213. In the example of fig. 14, the third capacitance signal 1203 crosses the reference compensated second threshold capacitance 1212 at times T5, T6, and T9. Thus, different interrupt signals or interrupt signal timings may be provided depending on whether the threshold is reference compensated. For example, the fourth interrupt signal INT4 may be generated and provided between times T5 and T6. If the second threshold capacitance 1212 is used without reference compensation, the fifth interrupt signal INT5 may be generated and provided at time T8. However, if the reference compensated second threshold capacitance 1212 is used, a fifth interrupt signal INT5 is generated and provided at time T9, as shown when the third capacitance signal 1203 crosses the compensated second threshold capacitance 1212.

Logic circuitry may be used to monitor and update the threshold capacitance value. Such logic circuitry may be incorporated with the footpresence sensor 310 or with the processor circuit 320. The updated threshold level may be automatically provided and stored in on-chip RAM. In an example, no input or confirmation from the user is required for the threshold update.

Fig. 15 generally shows a chart 1500 of fourth time-varying information from a capacitive foot presence sensor. The example of fig. 15 illustrates how reference capacitance changes are considered, such as changes due to various environmental conditions, changes in usage scenarios, or changes due to wear or degradation of footwear components. Examples include a fourth capacitance signal 1204 plotted on graph 1500, having an adaptive threshold capacitance 1214. The fourth capacitance signal 1204 may be provided by the foot presence sensor 310. The adaptive threshold capacitance 1214 may be used to help compensate for environmental or use case related changes in the capacitance measured by the foot presence sensor 310.

In an example, the foot presence sensor 310 or the processor circuit 320 is configured to monitor a change in signal amplitude of the fourth capacitance signal 1204, for example, a change greater than a specified threshold amplitude metric. That is, when the fourth capacitance signal 1204 includes an amplitude change that meets or exceeds a specified threshold capacitance amplitude ΔC, then the foot presence sensor 310 or the processor circuit 320 may provide an interrupt signal.

In an example, the sensed or measured capacitance value of the fourth capacitance signal 1204 is compared to a reference capacitance or baseline, and the reference or baseline may be updated at specified or time-varying intervals. In fig. 15, reference updates occur periodically at times T11, T12, T13 as shown. Other intervals or updates in response to other trigger times may additionally or alternatively be used.

In the example of fig. 15, the initial reference capacitance may be 0, or may be represented by the x-axis. After the fourth capacitance signal 1204 increases by more than the specified threshold capacitance amplitude Δc relative to the previously specified reference, the sixth interrupt signal INT6 may be provided at time T11. In the example of fig. 15, the interrupts may be provided at periodic intervals, however, in other examples, the interrupts may be provided while identifying a threshold change in capacitance.

After the identified threshold change, for example at time T11, the reference or baseline capacitance may be updated to the first capacitance reference C1. After time T11, foot presence sensor 310 or processor circuit 320 may be configured to monitor the signal for subsequent changes in fourth capacitance signal 1204 by at least Δc, i.e., find the capacitance value of c1+Δc or c1- Δc.

In examples that include a first identified capacitance increase, the interrupt signal state may be changed in response to the identified capacitance decreasing at a subsequent time. However, if a further capacitance increase is identified at a later time, the reference capacitance may be updated and a subsequent comparison may be made based on the updated reference capacitance. This scenario is shown in fig. 15. For example, at time T12, a capacitance increase in the fourth capacitance signal 1204 is detected, and the reference may be updated to the second capacitance reference C2. Since the first and subsequent second capacitance changes represent increases, the state of the sixth interrupt signal INT6 may be unchanged. At time T13, a decrease in capacitance in the fourth capacitance signal 1204 is detected, and the reference may be updated to the third capacitance reference C3. Since the capacitance change at time T13 is a decrease that is greater than the specified threshold capacitance magnitude deltac, the state of the sixth interrupt signal INT6 may change (e.g., from an interrupt asserted state to an deasserted state).

In an example, the change detected first at time T11 and the corresponding interrupt signal INT6 represent a foot that is sensed by foot presence sensor 310 and determined to be present in the footwear. The subsequent increase in reference capacitance represents a change in baseline capacitance measured by the foot presence sensor 310, for example, due to an environmental change at or near the sensor. The change detected at time T13 may be indicative of the foot being removed from the footwear and no longer sensed in the vicinity of foot presence sensor 310. Subsequent capacitance changes (e.g., at time T16) may indicate reinsertion of the foot into the footwear.

Fig. 16 generally illustrates a graph 1600 of time-varying information and signal morphology constraints from a capacitive foot presence sensor according to an example embodiment. Examples include fifth capacitance signal 1205 and sixth capacitance signal 1206 plotted on graph 1600. Graph 1600 also includes morphology limit 1601. The morphology limit 1601 may be compared to a sampled segment of the capacitance signal from the foot presence sensor 310. A comparison may be made using the foot presence sensor 310 or the processor circuit 320 to determine whether a particular sample segment meets the morphology limit 1601. In the example of fig. 16, the morphology limit defines a lower limit beyond which the indicated capacitance signal segment does not, or is likely not, indicate that a foot is present in the vicinity of the foot presence sensor 310.

The illustrated sample portion of the fifth capacitance signal 1205 meets the morphology constraint 1601. In the example of fig. 16, morphology constraints 1601 define a morphology that includes capacitive signal amplitude variation, or dip, dwell, and recovery. After identifying that the fifth capacitance signal 1205 meets all or part of the morphology limit 1601, an interrupt signal may be provided to indicate the presence of a foot or successful detection.

The illustrated sample portion of the sixth capacitance signal 1206 does not meet the morphology constraint 1601. For example, the sharp drop in the sixth capacitance signal 1206 and the long dwell time fall outside the limits defined by the morphology limit 1601, thus an interrupt signal may be retained, e.g., to indicate that the foot was not detected by the foot presence sensor 310.

The morphology limits 1601 may be fixed or variable. For example, the morphological limits may be adjusted based on information about reference capacitance, environment, footwear use case, user, sensitivity preferences, or other information. For example, the morphology limits 1601 may vary depending on the type of footwear used. That is, the morphological limit 1601 of basketball shoes may be different from running shoes, at least in part, because of the different geometry or materials of the shoes, or the expected amount of time a user wears or removes a particular article of footwear. In an example, morphology limits 1601 may be programmed by a user, for example, corresponding to a user-unique footwear put-on and put-off preference or program.

As explained above, the foot presence sensor 310 may have an associated fixed or variable baseline or reference capacitance value. The reference capacitance value may be a function of: electrode surface area, or electrode placement relative to a footwear component, or footwear orientation, or environment in which the sensor is used, or the footwear itself. That is, in the event that the foot is not present in the footwear, the sensor may have some associated capacitance value, and that value may be a function of the dielectric effect of one or more materials or environmental factors at or near the sensor. In an example, a orthotic insert (e.g., insole) in the footwear may change the dielectric properties of the footwear at or near the capacitive sensor.

In an example, the foot presence sensor 310 may be calibrated at the factory to include or use a fixed or static reference capacitance. In an example, the reference capacitance characteristics of foot presence sensor 310 may be adjusted from time to time during the life of the footwear, e.g., to accommodate different usage patterns, different environments, or different user preferences, etc.

In an example, parasitic capacitance from the environment, or from the degradation of components over time or component replacement, may compromise the accuracy of foot presence sensor 310. The processor circuit 320 may optionally be configured to calibrate the foot presence sensor 310 when a baseline or reference characteristic of the footwear changes (e.g., when the insole changes). In an example, the processor circuit 320 may be configured to automatically detect a baseline or reference capacitance change, or may be configured to update the baseline or reference capacitance in response to user input or command. In an example, foot presence sensor 310 may be calibrated each time the footwear is removed from the foot, or may be calibrated each time the footwear is charged. By periodically calibrating the baseline or reference capacitance characteristics, the foot presence sensor 310 may maintain its effectiveness over time.

Fig. 17 generally shows an example of a graphical representation 1700 of a capacitance-based foot presence sensor in a midsole of an article of footwear and located below a dielectric stack. The example 1700 includes a housing structure 150, which may include or use, for example, a lacing engine or drive mechanism 340 that is actuated based at least in part on information from a capacitive foot presence sensor 1701. The capacitive foot presence sensor 1701 may be configured to provide a capacitance or capacitance indication signal based on the presence or absence of the body 550 in the vicinity of the sensor.

One or more materials may be disposed between the body 550 and the capacitive foot presence sensor 1701, and the one or more materials may affect the sensitivity of the sensor, or may affect the signal-to-noise ratio of the signal from the sensor. In an example, the one or more materials form a dielectric stack. The one or more materials may include socks 1751, air gaps (e.g., due to arch height of the body 550 at or near the sensor), sock liners 1750, fasteners 1730 (e.g., velcro) or dielectric padding 1720, and so on. In an example, when the capacitive foot presence sensor 1701 is disposed inside the housing structure 150, the top wall of the housing structure 150 itself is part of a dielectric stack. In an example, the corrective insert may be part of a dielectric stack.

The inventors have recognized that providing a dielectric stack with a high relative permittivity or high k value may enhance the input sensitivity of the capacitive foot presence sensor 1701. Various high-k materials were tested and evaluated for effectiveness and suitability in footwear. The dielectric stack may include one or more components that are designated to have a durometer or durometer characteristic, to be comfortable under the foot in footwear, and to provide a sufficient dielectric effect to increase the sensitivity of the capacitive foot presence sensor 1701, e.g., relative to having an air gap or other low-k material in its place. In examples, suitable materials include materials that have good weatherability or durability, low temperature and high temperature resistance, and stress cracking resistance.

In an example, dielectric filler 1720 may include a neoprene member. The neoprene member comprises a closed cell foam having a shore a hardness value of about 30. In an example, dielectric filler 1720 may include rubber, plastic, or other polymer-based components. For example, dielectric filler 1720 may include an Ethylene Vinyl Acetate (EVA) member. The EVA component may have about 10% to 40% by weight vinyl acetate, the remainder being ethylene. Other ratios may be used. In an example, dielectric filler 1720 may include a material having enhanced conductive properties, including, for example, doped plastic or rubber. In an example, dielectric seal 1720 includes an EVA member doped with carbon, e.g., having a greater k value than an undoped EVA member having the same or similar ethylene to vinyl acetate percentage.

Fig. 18 generally illustrates an example including a graph 1800 showing the effect of a dielectric filler 1720 on a capacitance indication signal from a capacitive foot presence sensor 1701. In the graph 1800, the x-axis represents the number of digital samples and the y-axis represents the relative measure of capacitance detected by the capacitive foot presence sensor 1701, corresponding to elapsed time. The graph 1800 includes a time aligned superposition of a first signal 1801 indicative of capacitance and a second signal 1802 indicative of capacitance, the first signal 1801 indicative of capacitance corresponding to a first type of dielectric filler 1720 material, the second signal 1802 indicative of capacitance corresponding to a second type of dielectric filler 1720.

In an example, first signal 1801 corresponds to footwear having a first dielectric member provided as dielectric filler 1720. The first dielectric member may comprise, for example, polyurethane foam having a first dielectric k-value. The chart 1800 shows a number of examples of a body being inserted into and then removed from an article of footwear that includes a first dielectric member and a foot presence sensor 1701. For example, the first portion 1820 of the first signal 1801 includes a reference or baseline capacitance measured by the capacitive foot presence sensor 1701. In the example of fig. 18, the reference or baseline is normalized to a zero value. The reference or baseline condition may correspond to the absence of a foot in the footwear. That is, first portion 1820 of first signal 1801 indicates that no foot is present in the footwear. At a time corresponding to about sample 600, body 550 may be inserted into the footwear and may be located at or near capacitive foot presence sensor 1701 and the first dielectric member. After insertion, the amplitude of the first signal 1801 changes, e.g., by a first amount 1811, and indicates that the foot (or other body) is present in the footwear. In the example of fig. 18, the body 550 is present in the footwear for a duration corresponding to the second portion 1821 of the first signal 1801, e.g., corresponding to approximately samples 600-1400. At a time corresponding to about sample 1400, body 550 may be removed from the footwear. When the body 550 is removed, the first signal 1801 may return to its reference or baseline value.

In the example of fig. 18, second signal 1802 corresponds to footwear having a second dielectric member provided as dielectric filler 1720. The second dielectric member may comprise various materials in addition to the first dielectric member. In an example, the second dielectric member comprises neoprene foam having a second dielectric k value that exceeds the first dielectric k value of the first dielectric member described above. In an example, the second dielectric member includes an EVA member (e.g., doped with carbon or other material to enhance the dielectric properties or k-value of the member) having a third dielectric k-value that exceeds the first dielectric k-value of the first dielectric member.

The chart 1800 shows a number of examples of a body being inserted into and then removed from an article of footwear that includes a second dielectric member and a foot presence sensor 1701. First portion 1820 of second signal 1802 indicates a reference or baseline capacitance measured by capacitive foot presence sensor 1701, and in the example of fig. 18, first portion 1820 of second signal 1802 indicates the absence of a foot in the footwear. At a time corresponding to about sample 600, body 550 may be inserted into the footwear and may be located at or near capacitive foot presence sensor 1701 and the second dielectric member. After insertion, the amplitude of the second signal 1802 changes, e.g., by a second amount 1812, and indicates that a foot (or other body) is present in the footwear. In an example, the second amount 1812 exceeds the first amount 1811. The difference in amplitude variation is due to the type of material used for the dielectric filler 1720. That is, when different dielectric stacks are used, the magnitudes of the first signal 1801 and the second signal 1802 indicative of capacitance may be different. When the dielectric stack includes a high-k dielectric filler 1720, then the difference in amplitude, or from baseline, is greater than when the dielectric stack includes a low-k dielectric filler 1720.

In an example, the orthotic insert comprises a portion of a dielectric stack in footwear. The present inventors have conducted various tests to evaluate the impact of various orthotic inserts on capacitive foot sensing techniques. Some of the test results are generally illustrated in fig. 23 and discussed below. Full and partial length orthotic insoles were tested. Adding regular (partial length) corrections to the footwear increases the overall dielectric effect of the stack and reduces the sensitivity to the electric field present by the foot. In the presence of the orthotic, the sensed signal amplitude (e.g., corresponding to the sensed capacitance change) also decreases. However, the RMS amplitude of the noise floor is similar whether or not an orthosis is used. The response under load and unload conditions is also similar.

Based on the results of the orthotic test, in the case of a regular full length orthotic, the use of capacitive sensing to detect the presence of the foot is feasible for signal to noise ratio resolution. Using partial or full length orthotics, SNR exceeding a required minimum of about 6db can be used to resolve foot presence and can be used under light and heavy load conditions. In an example, foot presence sensor 310 may include using a range of capacitive offsets to compensate for the added dielectric effects of the orthotic.

The change in air gap between the full length orthotic and the electrode of foot presence sensor 310 may correspond to a measurable change in SNR as a function of applied load. For example, as shown in the example of fig. 18, when a high-k dielectric material is disposed at or near the capacitive foot presence sensor, then the SNR may be improved relative to examples that include or use a low-k dielectric material.

The different foot regions were found to behave similarly under low load conditions, such as under an orthotic, with no significant deformation of the gap distance. However, under high load conditions, such as when a user stands, the arch region of the orthotic may be compressed and the air gap may be significantly minimized or eliminated. Thus, in a sensed condition, the magnitude of the electric field tested in the presence of the orthotic may be similar to the electric field measured using a production or OEM insole. In examples where an orthotic or OEM generated insole forms an air gap between the foot presence sensor 310 and the body to be tested, various materials may be provided or added to compensate or fill the air gap. For example, a gap-filling foam, such as neoprene or doped EVA, may be provided on the underside of the full length orthotic.

In an example, including the orthotic in the insole increases the overall dielectric thickness of the dielectric stack and reduces the electric field sensitivity of the capacitive sensor to the presence of the foot. In other words, when a corrective insert is used, the signal amplitude derived from the capacitive sensor generally decreases. The RMS amplitude of the noise characteristics is observed to be substantially similar whether or not an orthosis is used. It was also determined that the dielectric member that occupies between the sensing electrode of the capacitive sensor and the lower surface of the orthotic would have a significant impact on the sensitivity of the capacitive sensor. The signal amplitude of the polyurethane foam (e.g., a k value of 1.28) can be reduced by about 70% compared to using neoprene foam having a dielectric constant or k value of about 5.6. With equal noise amplitudes, this corresponds to an SNR difference of about 4.6 dB. Thus, in the case of carbon fiber correction, the use of capacitive sensing for detecting the presence of the foot is feasible for signal-to-noise ratio. For example, the SNR exceeds the minimum of 6dB required for the presence of the resolving foot.

Fig. 19 generally illustrates an example of a graph 1900 that shows a portion of a third signal 1803 from a capacitance-based foot presence sensor in footwear that indicates capacitance. In graph 1900, the x-axis represents the number of digital samples and the y-axis represents the relative measure of capacitance detected by capacitive foot presence sensor 1701, corresponding to elapsed time. Information from third signal 1803 may be used to determine whether the user is applying downward force to the footwear, such as to identify whether the user is sitting or standing, or to determine a number of steps, or to determine a user gait feature, and so forth. In the example of fig. 19, a mutual capacitance sensing mode is used. In the mutual capacitance sensing mode, as shown, the increased capacitance detected by the sensor corresponds to a decrease in the signal. In another example, a self-capacitance sensing mode may be used. In the self-capacitance mode, the increased capacitance detected by the sensor (e.g., corresponding to compression of the foam insert on the sensor) will correspond to an increase in the signal.

In the example of fig. 19, at an initial time, e.g., corresponding to sample "0" on the x-axis, the third signal 1803 may have a reference or baseline value of about 0 on a relative capacitance scale. At 1901, or about sample 175 on the x-axis, third signal 1803 includes a footwear donning event, which corresponds to body 550 being inserted into footwear, for example. Third signal 1803 includes a footwear removal event at 1910, or at about sample 10000, after which third signal 1803 returns to a baseline value.

The example of fig. 19 also includes a specified threshold 1920. Threshold 1920 may correspond to a relative capacitance value that indicates that body 550 is present in the footwear. For example, when the foot or body 550 is present in the footwear, the relative capacitance indicated by the third signal 1803 exceeds a threshold 1920, and when the foot or body 550 is not present in the footwear, the relative capacitance may drop below the threshold 1920. Various methods or techniques may be used to dynamically adjust threshold 1920, such as described further herein, for example, to account for environmental changes or changes in footwear materials.

Between footwear pull-on events at 1901 and 1910, corresponding to, for example, the spacing between samples 175 and 10250, respectively, the wearer of the article of footwear may transition between a sitting position and a standing position multiple times. The transition between sitting and standing may correspond to fluctuations in the third signal 1803, for example, due to compression and relaxation of the footwear material that forms a dielectric stack on the capacitive sensor providing the third signal 1803. That is, when a user stands up and applies a downward force to the dielectric stack, one or more materials in the dielectric stack may compress and the user's foot may move closer to the capacitive sensor, thereby changing the relative capacitance measured using the sensor. When the user sits down and reduces the downward force on the dielectric stack, then the dielectric stack material may relax or stretch and the user's foot may move away from the capacitive sensor.

The donning event 1901 includes a turbulent portion of the third signal 1803. That is, the third signal 1803 does not exhibit a smooth or gentle transition, but rather rapidly and irregularly fluctuates as the user places his or her foot in place within the footwear. In an example, donning event 1901 includes lacing, such as automatic or manual lacing, which may correspond to a user applying various forces on the footwear material (including the dielectric stack), and the user adjusting the tension of the footwear around the user's foot, thus adjusting the position of the user's foot relative to the capacitive sensor accordingly. In the example of fig. 19, after the donning event at 1901, the user may sit for a first duration 1931, e.g., corresponding to samples 200-275. The third signal 1803 may have an average value of about 220 relative capacitance units over the first duration 1931.

After a first duration 1931, the user can stand such that the material(s) of the dielectric stack compress and allow the user's feet to access the capacitive sensors underneath the stack. When the user is fully standing and compressing the dielectric stack, the third signal 1803 may have an average of about 120 relative capacitance units over the second duration 1932. That is, when the user transitions from a sitting position to a standing position, or when the user transitions from applying a minimum force to the dielectric stack to applying a greater or maximum force to the dielectric stack, the amplitude of the third signal 1803 may change by the first amplitude deformation 1951, thereby changing the dielectric properties of the dielectric stack itself. In an example, the first magnitude deformation 1951 may correspond to a magnitude of a force exerted on the dielectric stack. That is, the first amount of amplitude deflection 1951 may be used to determine a weight of the user or whether the user is running or walking, for example, because a greater force is expected to be applied to the dielectric stack when the user is running than when walking.

In the example of fig. 19, at about sample 375, when the user returns to the sitting position, the third signal 1803 returns to a value of about 220 relative capacitance units. The user sits down for a third duration 1933 before the next relative capacitance change.

The dashed portion of the third signal 1803 (after approximately sample 500 in the example of fig. 19) represents the passage of time and the dimensional change of the x-axis. In an example, samples 0 through 500 correspond to times when the footwear containing the capacitive sensor is new or when a new dielectric stack is used with the footwear. A sample after about sample 9800 may correspond to a time of older or partially worn footwear, or a time when a portion of the dielectric stack is compressed without full retraction or expansion with relaxation or no use.

In the example of fig. 19, the third signal 1803 indicates a number of user transitions between sitting and standing positions. In an example, fourth duration 1934 and sixth duration 1936 correspond to a sitting position with minimal force or pressure applied to the dielectric stack in the footwear. The fifth duration 1935 corresponds to a standing position with an elevated force applied to the dielectric stack. In an example, fourth duration 1934 and sixth duration 1936 can correspond to an average of about 240 relative capacitance units. That is, the average of fourth duration 1934 and sixth duration 1936 may exceed the average of first duration 1931 and third duration 1933 (which is about 220 units). In an example, the difference between the average values may be due to wear of one or more portions of the dielectric stack or other footwear material that may change over time as the footwear is used. In an example, the fifth duration 1935 can correspond to an average of about 150 relative capacitance units, which exceeds an average of about 120 units of the third duration 1933. Furthermore, the difference between sitting and standing positions, i.e. the difference between the stress or the absence of the dielectric stack, may vary for the case of new and old footwear. The first amplitude deflection 1951 indicates about 200 units of change in relative capacitance for new footwear between standing and sitting and the second amplitude deflection 1952 indicates about 150 units of change in relative capacitance for old footwear between standing and sitting. In the example of fig. 19, fourth through sixth durations 1934-1936 further indicate relatively noisy signals compared to first through third durations 1931-1933, which may be due to wear of the footwear or sensor components.

Thus, fig. 19 shows that information from third signal 1803 may be used to indicate a footwear lifecycle state or footwear usage characteristics, and so on. For example, this information may be used to help prevent injury to the user by reporting or alerting the user that one or more of the footwear components have worn or exhausted, and may no longer provide optimal or sufficient cushioning or foot retention. For example, information from third signal 1803 may be used to determine a lifecycle state of a footwear component, such as an insole component, orthotic insert, or other component of the footwear.

In an example, information from the capacitive foot sensor may be used to derive or determine stride frequency information, which in turn may be used as a pedometer or pedometer, for example, when the user's stride is known or determinable. Referring again to fig. 19, fluctuations in the third signal 1803 may correspond to different ambulatory events. For example, the second duration 1932 may correspond to an interval containing a first portion of the user's stride, such as when the first foot of the user is grounded and the user's body weight applies a force to the user's footwear, and the footwear includes a capacitance-based foot presence sensor that provides the third signal 1803. Following the second duration 1932, the user may transfer his or her weight from the user's first foot to his or her second foot. As a result, the pressure or force exerted by the user on the footwear may be reduced and a corresponding change in third signal 1803 may be observed. For example, the amplitude of the third signal 1803 may be increased, such as by increasing the first amplitude distortion 1951. When the user steps back again and returns to the first foot, the amplitude of the third signal 1803 may decrease, for example, the same or similar to the first amplitude distortion 1951. In an example, the amplitude variation may depend on, or may be related to, a force exerted by the user on the footwear, which in turn may correspond to a speed at which the user walks or runs. For example, a larger amplitude deflection may correspond to running pace, while a smaller variation may correspond to walking pace. Thus, one or both of the magnitude change amount and the frequency or rate of magnitude change events may be used to determine the pace of the user.

In an example, the step interval or number of steps may be determined using the duration, interval, or sample count of the specified portion of the third signal 1803. For example, the first duration 1931 may have a sample count of approximately 75 samples and the second duration 1932 may have a sample count of approximately 50 samples. If the first duration 1931 corresponds to a first portion of a user's walking or stepping cycle when the first foot is off the ground and the second duration 1932 corresponds to a subsequent second portion of the user's walking or stepping cycle when the first foot is on the ground, the user may have a step interval of approximately 125 samples. Depending on the sample rate, the step interval may be associated with a walking or running pace, for example, using processor circuit 320 to process sample count information.

In an example, the duration, interval, or sample count between signal amplitude changes of the third signal 1803 may be used to determine a step interval or number of steps. Amplitude variations, such as greater than a specified threshold amplitude variation amount, may be identified by the processor circuit 320, and then the processor circuit 320 may calculate or identify a length of the interval between the identified amplitude variations. For example, the processor circuit 320 may identify the beginning of the second duration 1932 as about the sample 325, e.g., corresponding to an amplitude change observed in the third signal 1803 that is greater than a specified threshold change. The processor circuit 320 may identify the end of the second duration 1932 as approximately the sample 375, e.g., corresponding to a subsequent amplitude change observed in the third signal 1803 that is greater than a specified threshold change. The processor circuit 320 may calculate the difference between the sample counts and determine that the second duration 1932 is approximately 50 samples in duration. Processor circuit 320 may similarly determine the duration or sample length of any one or more segments of third signal 1803. The processor circuit 320 may then determine the step interval, and the step interval may be used to determine the distance traveled or the rate of user movement. In an example, information about a user's stride may be used with the step interval information to determine a distance traveled.

In an example, the stride of the user is not specified or known. The user's stride may optionally be determined using information from one or more other sensors, such as an accelerometer or a position sensor (e.g., a GPS sensor) and coordinated with foot sensor information. For example, information from the position sensor may indicate the total distance the user has moved over a specified duration. Processor circuit 320, or other processor affiliated with the footwear, may receive third signal 1803 and correlate the number of signal amplitude change events with the number of steps and distance traveled to determine an average user step number or stride. For example, if the user has traveled 100 meters in 30 seconds and the capacitance indicating signal from the foot sensor indicates 100 signal amplitude change events in the same 30 second intervals, the processor circuit 320 or other processor may determine that the user's stride is approximately 100 meters/100 amplitude change events = 1 meter per amplitude change event.

In an example, the information from the third signal 1803 may be used to determine a user gait feature, or a change in user gait. For example, the processor circuit 320 may be configured to monitor the capacitance indication signal over time, such as to identify a change in the signal. For example, the processor circuit 320 may monitor a first (or other) duration or a first ambulatory event after detecting a wearable event. Typically, each time a user wears footwear, the user expects to begin walking or running in a similar manner, e.g., using a similar gait. The user may be alerted if the processor circuit 320 detects a deviation from a given baseline or average signal characteristic after the footwear is worn. Similarly, the processor circuit 320 may be configured to detect usage characteristics or deviations that may be associated with user fatigue or emotion, which may in turn lead to injury. For example, a deviation from a given baseline or reference signal characteristic may indicate that the foot or ankle is rotating or sliding within the footwear, for example, because a foot position change may correspondingly change the dielectric characteristics at or above the capacitance-based foot presence sensor. In examples that include an automatic lacing engine, information regarding changes in foot position may be used to automatically tighten footwear around a user's foot to help prevent injury to the user.

Fig. 20 generally shows an example of foot presence signal information over a plurality of sitting periods. Examples include a graph 2000 showing the relationship between time (x-axis) and "count" (y-axis). The count corresponds to the output of the capacitive foot sensor. For example, the count may correspond to a digital signal from an analog-to-digital converter that receives an analog output from a capacitive sensor.

In the example of fig. 20, a zero count indicates a reference condition, e.g., corresponding to the absence of a foot in the footwear including the sensor. A count greater than zero indicates that the capacitive foot presence sensor senses something other than a step-free condition, such as a foot or other body or object present in or near the sensor and thus the footwear. The magnitude of the count corresponds to the position of the target (e.g., foot) of the sensor relative to the electrodes of the sensor. In some examples, the magnitude of the count corresponds to a force applied by the foot to the sole of the footwear, such as described in the example of fig. 19 above. For example, when the foot is present in the footwear and the wearer is sitting, and therefore does not exert a significant force on the sole of the footwear, the sensor may register a first, lesser number of counts. When the foot is present in the footwear and the wearer is standing, and therefore applies a relatively large force to the sole of the footwear, then the sensor may register a second, greater number of counts. These and other count amplitude variation conditions are generally shown in fig. 20. In the example of fig. 20, a self-capacitance sensing mode is used. Thus, as shown, the detected increase in capacitance corresponds to an increase in signal.

In the example of fig. 20, the no foot condition interval is indicated at a first interval 2001 from time zero to about time 900. During the no foot condition of the first interval 2001, the sensor records about zero counts. After the first interval 2001 of the no foot condition, the first donning interval 2002 is indicated as from about time 900 to about time 1250. During the first wear interval 2002, the count may fluctuate as the wearer's foot enters the shoe and sits against the footbed, and as the wearer adjusts the shoe, such as any wrinkles in the insert including flattening the support foot.

After the first wear interval 2002, the first sitting interval 2003 is indicated from about time 1250 to time 1750. During the first sitting interval 2003, the count stabilizes at a baseline value of about 150 counts. During the first sitting interval 2003, the wearer is substantially stationary and remains in a relaxed posture. The count amplitude remains at a substantially constant value as long as the wearer remains stationary. After the first sitting interval 2003, a first foot lift interval 2004 is indicated from about time 1750 to time 2200. At the first foot lift interval 2004, the wearer remains seated, but lifts his or her foot off the ground, thereby removing any downward force applied to the footwear with the sensors. Since the wearer's foot is still physically present in the footwear during the first foot lifting interval 2004, the count amplitude remains greater than zero, but less than that observed during the first sitting interval 2003, because less force is applied to the sensor. In the example of fig. 20, the sensor records about 100 counts during the first foot lift interval 2004.

After the first foot lift interval 2004, a first stance interval 2005 is indicated from about time 2200 to time 2750. During the first stance interval 2005, the wearer places his or her foot on the ground and upright, thereby exerting a downward force on the footwear and sensors. As observed from fig. 20, the count amplitude increases to about 300 counts during the first stance interval 2005. The count amplitude may be greater than that observed during the first sitting interval 2003 and the first foot-lifting interval 2004 because during the first standing interval 2005 the wearer exerts a relatively large force on the footwear that compresses the dielectric member over the electrode(s) of the capacitive sensor, thereby increasing the capacitance detected by the sensor. After the first standing interval 2005, a first walking/walking interval 2006 is indicated from about time 2750 to time 3200. During the first walking/walking interval 2006, the wearer walks or walks wearing footwear. The count amplitude fluctuates during the first walking/walk interval 2006 and the fluctuation corresponds to the wearer's step period. For example, the peak or maximum value of the count amplitude during the first walking/walk interval 2006 corresponds to an example when the wearer applies a force to footwear that includes the sensor, such as when the wearer's foot contacts the ground. The count amplitude valley or minimum during the first walking/walk interval 2006 corresponds to an instance of the wearer lifting the foot. The peak amplitude value generally exceeds the amplitude of the count value observed during the first stance interval 2005, and the minimum amplitude value generally corresponds to the value observed during the first foot lifting interval 2004. In an example, the count flat area corresponds to a duration of time the foot is on the ground (e.g., corresponding to a walking event) or a duration of time the foot is lifted off the ground. Thus, the travel rate of the user may be discerned or determined based on the relative length of each flat region.

After the first walking/walk interval 2006, a second sitting interval 2007 is indicated from about time 3200 to time 3600. In the example of fig. 20, the count amplitude during the second sitting interval 2007 is smaller than the count amplitude observed during the first sitting interval 2003. This change can be attributed to, among other factors: a change in baseline or reference capacitance of the sensor, an environmental effect, or a posture of the wearer after the first walking/walk interval 2006.

After the second sitting interval 2007, the first unseating interval 2008 is indicated from about time 3600 to about time 3750. During first take-off interval 2008, the count may fluctuate as the wearer's foot is moved away and removed from the footwear. After the first take-off interval 2008, the count amplitude returns to its baseline value of about zero counts, corresponding to a no foot condition.

After returning to the zero count at about time 3750, the example of fig. 20 includes a second cycle beginning at about time 4500 that includes another wear interval, a sitting interval, a foot lifting interval, a standing interval, a walking/walking interval, a second sitting interval, and a dechucking interval, in that order.

In an example, a foot presence threshold may be used to determine whether a foot is present in footwear that includes a capacitive foot presence sensor. For the sensor configuration used to generate the example of fig. 20, for example, the foot presence threshold may be selected to be about 30 signal counts from the sensor. When a count greater than a specified number is observed, the foot presence threshold may indicate that the foot is present in the footwear (or that there is a high likelihood that the foot is present in the footwear). Similarly, when less than a specified number of counts are observed, the foot presence threshold may indicate that the foot is not present in the footwear (or that there is a high likelihood that the foot is not present in the footwear).

In an example, the foot presence threshold may be adjusted or altered, for example, in response to changes in sensor characteristics, changes in environmental impact on the sensor, and changes in user preferences. For example, if the sensor electrode is damaged or changed, the baseline capacitance value of the sensor may change, and accordingly the reference measurement of the sensor may change. In an example, various electric and/or magnetic fields can affect the behavior of the sensor, which can result in a change in the baseline capacitance value of the sensor. In an example, a user may adjust the foot presence sensing sensitivity of the sensor, e.g., to make the sensor (and its triggered function) more or less responsive to foot detection events. The foot presence threshold may be adjusted to accommodate any one or more of these or other changes without losing its foot presence sensing function.

Fig. 21A-21D generally illustrate examples of different planar electrode assembly configurations. The shape or profile of each assembly generally conforms to the shape of the lacing engine housing or shell configured to house the electrode assemblies, although other shapes may be similarly used. In the example of fig. 21A-21D, the electrode assembly is generally planar and includes a first conductive region or electrode about a perimeter (shown generally as a shaded region) and a second non-conductive region positioned generally centrally and surrounded by the first conductive region. Other examples may have multiple conductive and non-conductive regions, e.g., may be arranged side-by-side or concentrically.

Fig. 21A includes a first electrode assembly 2101 that includes a central first non-conductive region 2131 having a first surface area A1 and a first electrode region 2121 having an average first thickness T1. In an example, the average first thickness T1 is about 2 millimeters and includes a conductive band or loop about 2mm wide that extends substantially around the perimeter of the first electrode assembly 2101. In an example, the assembly includes a first non-conductive boundary 2111 outside of the first electrode region 2121.

Fig. 21B includes a second electrode assembly 2102 including a central second nonconductive region 2132 having a second surface area A2 that is less than A1. The second electrode assembly 2102 includes a second electrode region 2122 having an average second thickness T2 that is greater than T1. In an example, the average second thickness T2 is about 4 millimeters and includes a conductive band or loop about 4mm wide that extends substantially around the perimeter of the second electrode assembly 2102. In an example, the assembly includes a second non-conductive boundary 2112 outside of the second electrode region 2122.

Fig. 21C includes a third electrode assembly 2103 including a central third non-conductive region 2133 having a third surface area A3 that is less than A2. The third electrode assembly 2103 includes a third electrode region 2123 having an average third thickness T3 that is greater than T2. In an example, the average third thickness T3 is about 6 millimeters and includes a conductive band or ring about 6mm wide that extends substantially around the perimeter of the third electrode assembly 2103. In an example, the assembly includes a third non-conductive boundary 2113 outside of the third electrode region 2123.

Fig. 21D includes a fourth electrode assembly 2104 including a center flood (flood) electrode region 2124 having a surface area greater than any of the first through third electrode regions 2121-2123 of fig. 21A-21C. In an example, the assembly includes a fourth non-conductive boundary 2114 outside the central flooded electrode area 2124. That is, the fourth electrode assembly 2104 includes an electrode that occupies substantially all of the available surface area, but does not include a central non-conductive region.

Foot presence sensor 310 is generally discussed herein as including the use of an electrode assembly, such as including one or more electrodes disposed under the foot. However, a plurality of electrodes may be used. The plurality of electrodes may be disposed adjacent to one another or may be distributed or disposed at different locations in or on the footwear. For example, a first electrode assembly of foot presence sensor 310 may be disposed in the arch region and a second electrode assembly of foot presence sensor 310 may be disposed in the toe region of the footwear. The different electrode assemblies may be commonly controlled by the processor circuit 320 and share information. Information from a plurality of different electrode assemblies may be used together to determine the position or status of the foot within the footwear. For example, using at least two different electrode assemblies spaced apart along the length of the footwear or along the toe travel path, information may be collected from the electrode assemblies over time and used to accurately determine the position of the foot within the footwear. For example, as the foot enters or leaves the footwear, the signal from the first component may transition state before the signal from the second component. Information regarding the duration between state changes may be used to determine whether the foot is present in the footwear or whether the foot is fully seated within the footwear. In an example, the electrode assembly may be disposed in a heel portion or a toe portion of the footwear, and may be used, for example, to evaluate the fit of the footwear to a particular foot.

Fig. 22 generally shows an example of a graph showing a relationship between the sensitivity of the capacitive sensor and the shape of the sensor. Each of the illustrated curves corresponds to data obtained using one of the different electrode assemblies from the example of fig. 21A-21D. For example, a first curve 2201 corresponds to a first electrode assembly 2101 (e.g., having a first electrode region 2121 that is 2mm wide), a second curve 2202 corresponds to a second electrode assembly 2102 (e.g., having a second electrode region 2122 that is 4mm wide), a third curve 2203 corresponds to a third electrode assembly 2103 (e.g., having a third electrode region 2123 that is 6mm wide), and a fourth curve 2204 corresponds to a fourth electrode assembly 2104 (e.g., having a flooded electrode region 2124).

In the example of fig. 22, the first through fourth curves 2201-2204 indicate a relationship between foot impact force on one particular capacitive sensor and the number of resulting counts from the sensor (see discussion above regarding "counts" as output from the capacitive sensor, or from a processor, such as an ADC circuit coupled to the capacitive sensor). For example, the first curve 2201 indicates that when a weight of about 20 pounds is applied to a capacitive sensor including the first electrode assembly 2101, then the number of resulting counts from the sensor is about 20. The first curve 2201 also indicates that when a weight of about 100 pounds is applied to the same capacitive sensor, then the number of resulting counts from the sensor is about 70. Over the illustrated interval of force from 20 to 80 pounds, the sensor comprising the first electrode assembly 2101 indicates a difference of about 50 counts.

In the example of fig. 22, a second curve 2202 indicates that when a weight of about 20 pounds is applied to a capacitive sensor including the second electrode assembly 2102, then the number of resulting counts from the sensor is about 60. The second curve 2202 also indicates that when a weight of about 100 pounds is applied to the same capacitive sensor, then the number of resulting counts from the sensor is about 170. Over the illustrated interval of force from 20 to 80 pounds, the sensor comprising the second electrode assembly 2102 indicated a difference of about 110 counts.

In the example of fig. 22, a third curve 2203 indicates that when a weight of about 20 pounds is applied to a capacitive sensor including the third electrode assembly 2103, then the number of resulting counts from the sensor is about 75. The third curve 2203 also indicates that when a weight of about 100 pounds is applied to the same capacitive sensor, then the number of resulting counts from the sensor is about 190. Over the illustrated interval of force from 20 to 80 pounds, the sensor including the third electrode assembly 2103 indicates a difference of about 115 counts.

In the example of fig. 22, a fourth curve 2204 indicates that when a weight of about 20 pounds is applied to a capacitive sensor including the fourth electrode assembly 2104, then the number of resulting counts from the sensor is about 80. The fourth curve 2204 also indicates that when a weight of about 100 pounds is applied to the same capacitive sensor, then the number of resulting counts from the sensor is about 255. Over the illustrated interval of force from 20 to 80 pounds, the sensor comprising the fourth electrode assembly 2104 indicates a difference of about 175 counts.

Each different sensor electrode assembly or configuration indicates a substantially linear relationship over the weight interval shown. However, different slopes of the first through fourth curves 2201-2204 indicate different sensor sensitivities to weight changes. For example, the first curve 2201 indicates that the first electrode assembly 2101 has relatively little sensitivity to weight change, showing a 50 count difference at a 60 pound force swing. In contrast, the fourth curve 2204 indicates that the sensitivity of the fourth electrode assembly 2104 to weight changes is relatively large and shows a 175 count difference at the same oscillation of 60 lbf. Thus, in some examples, a sensor incorporating or using the fourth electrode assembly 2104 may provide greater resolution and more information about weight change related events, such as standing, sitting, or walking/walking events.

Fig. 23 generally illustrates an example of a graph showing the relationship between sensor sensitivity and various types of corrective inserts. As explained above, the orthotic insert may comprise a portion of a dielectric stack in footwear. The inventors performed various tests using the planar electrode configuration discussed above to evaluate the impact of various corrective inserts on capacitive foot sensing techniques. In the example of fig. 23, the third electrode assembly 2103 (e.g., having a 6mm wide conductor) is used during testing. Full and partial length orthotic insoles were tested. Adding regular (partial length) corrections to the footwear increases the overall dielectric effect of the stack and reduces the sensitivity to the electric field present by the foot. In the presence of the orthotic, the sensed signal amplitude (e.g., corresponding to the sensed capacitance change) also decreases. However, the RMS amplitude of the noise floor is similar whether or not an orthosis is used. The response under load and unload conditions is also similar. In the example of fig. 23, a baseline or reference capacitance or offset is established for each tested insert to zero the test system.

In the example of fig. 23, a first orthotic curve 2301 corresponds to a fiberglass insert, a second orthotic curve 2302 corresponds to a rigid polymeric insert, a third orthotic curve 2303 corresponds to a polyurethane insert (e.g., a "standard" or factory supplied insole material), and a fourth orthotic curve 2304 corresponds to a carbon fiber insert. Each of the first through fourth orthotic curves 2301-2304 indicates that the substantially linear relationship between force and sensor output or count (see, e.g., fig. 22) remains substantially unchanged when the orthotic insert is used.

In the example of fig. 23, the baseline or reference capacitance value may be different for each insert. In an example, the carbon fiber insert has a greater sensor capacitance relative to other inserts. In the example of fig. 23, the sensor response (as shown by the slope) of a given insert decreases with increasing stiffness as long as the insert is not conductive. In other words, a stiffer or stiffer insert generally corresponds to a flatter response curve. Since carbon fibers are conductive, the curve is instead steepest in the test. This capacitance increase with compression is greatest because the conductive insert directs the electric field from the sensor back to signal ground via a shorter, higher capacitance path than when other inserts are used.

Fig. 24 generally illustrates an example of a graph 2400 that shows a relationship between capacitive sensor response and a change in fluid saturation of one or more components of footwear that includes capacitive sensors. The example of graph 2400 illustrates the effect of simulated perspiration applied to an ankle of a foot worn with a sock and placed within an article of footwear including a capacitive sensor. Examples correspond to tests performed in which the capacitive sensor was monitored over time and over multiple sitting/standing cycles as sweat agents were added to the test assembly.

The test assembly includes a foot equipped with a sock and footwear including a foot presence sensor according to one or more embodiments discussed herein. Perspiration is simulated by introducing saline solution into the ankle region of the foot. Approximately 10 milliliters of saline solution was added at each test interval, such as the interval shown in graph 2400 of fig. 24. The volume label indicates the cumulative total of solution added.

The example of fig. 24 begins with a brief first interval 2401 in which no foot is present in the footwear. During the first interval 2401, the capacitive sensor output is substantially zero count. During the second interval 2402, the foot is present in the footwear and is substantially dry, and the count output record from the sensor records a non-zero baseline or reference value (e.g., about 140 counts). During the third interval 2403, the wearer stands, further increasing the count output from the sensor (e.g., to about 200 counts). After the third interval 2403, a number of sitting/standing cycles are consecutively performed, with simulated sweat or physiological saline being added to each cycle.

The example of fig. 24 generally indicates that sweat or moisture may affect the output count from the capacitive sensor. For example, the baseline or reference count value when the test component is dry and the test subject is seated (e.g., corresponding to the second interval 2402) may be less than the baseline or reference count value when the test component is wet (e.g., partially saturated) and the test subject is seated. In the example of fig. 24, the test assembly is substantially saturated after the addition of about 60 milliliters of simulated sweat. Thus, a relative tilt of the baseline or reference count value may be observed when between about zero and 60 milliliters of fluid is added, however, when more liquid than 60 milliliters is added, the baseline or reference count is relatively unchanged.

Although the baseline or reference conditions vary for sitting configurations that pass different levels of fluid saturation, the count difference between adjacent sitting durations (e.g., shown as flat valleys) and standing durations (e.g., shown as flat peaks) is substantially the same for any amount of simulated sweat or saturation. For example, as seen in fig. 24, the first count difference between the second interval 2402 and the third interval 2403 or under dry conditions is about 60 counts. The difference in counts between sitting and standing intervals under saturated conditions, for example at the 70mL indication on graph 2400, is observed as about 75 counts, or only about 15 counts from that observed under dry or unsaturated conditions. Thus, in the presence of varying baseline or reference capacitance conditions, information about footwear usage, including information about the presence or absence of a foot, or about forces exerted on the sensor (e.g., foot impact forces), may be determined from the sensor, which may be used to distinguish between sitting and standing postures.

Fig. 25 generally shows an example of the graph of fig. 24 showing the relationship between sensor response and simulated sweat with an average signal. In the example of fig. 25, an average curve 2410, calculated as a slow moving average of sensor counts, is applied to the graph 2400 of the example of fig. 24. The average curve 2410 may correspond to a reference capacitance value that varies over time and may be used as a reference to identify whether a foot is present in the footwear. For example, if the wearer removes his or her foot from the footwear, the absolute reference indicated by average curve 2410 may be used for subsequent sensor output comparisons, e.g., rather than relying on or using relative sensor information, e.g., previous footwear occupancy from the same or a different wearer. That is, information regarding the changing reference condition of the capacitive sensor (e.g., corresponding to a change in moisture in or around the sensor or its target) may be used to adjust a threshold value for use in determining whether footwear is present in the footwear, and so forth.

Fig. 26 generally illustrates an example of a foot presence sensor state diagram 2600, which may optionally include or use sweat compensation methods. The foot presence sensor state diagram 2600 includes a first box 2610 of states and a second box 2620 of states. A first block 2610 represents a base foot presence detection function of the system. A second block 2620 includes a compensation function that may optionally be used to increase automatic footwear operation, such as by updating a baseline or reference characteristic of a foot presence sensor in the footwear.

The example of fig. 26 illustrates how the state machine may interact with or use information from foot presence sensor 310 and processor circuit 320, such as to control one or more functions of the footwear. In an example, the foot presence sensor state diagram 2600 illustrates conditions under which an interrupt signal may be generated, e.g., in response to a user command. In an example, the user command includes a foot entering the article of footwear, and the footwear includes a foot presence sensor 310. In an example, FOOT presence sensor 310 may provide an interrupt, which may be received as event foot_ingess_egress in footwear system state diagram 3100 of fig. 31, as discussed below.

Foot presence sensor state diagram 2600 generally illustrates an example that includes monitoring signal information from foot presence sensor 310 and determining whether the signal information includes or represents an actionable change. The foot presence sensor state diagram 2600 generally illustrates how the foot presence sensor 310 applies compensation over time at low power, e.g., without waking up or using the footwear system state machine 3100. In an example, the foot presence sensor state diagram 2600 generally illustrates how the foot presence sensor 310 response or system response is adjusted to change a characteristic of the footwear, such as a change due to the user's sweat or moisture content of the footwear, a change due to compression or decompression of the footwear material, or a change due to an environment such as temperature or floor surface material.

The example of fig. 26 may begin at state 2601, where a footwear system including a foot presence sensor may be in a resting, dormant, or inactive state, such as when the foot is not present in the footwear, or when the foot is not in proximity to the foot presence sensor 310 in the footwear. Sensor activity may be monitored by a processor circuit, such as processor circuit 320, for example, according to a specified duty cycle or in response to a command from a user. When the sensor indicates a non-zero or non-baseline response, then the processor circuit may wake up other circuits to determine whether the non-zero response indicates foot presence or noise. For example, when the footwear is worn and the capacitive sensor records a non-reference or baseline capacitance, a specified capacitance threshold may be met or exceeded, waking up further processing to verify whether the foot is present in the footwear.

At state 2602, an example includes filling a memory buffer with sensor data. The collected data is sufficient to determine the presence or absence of a foot, or to discern a foot presence signal from noise. When the buffer has a specified amount of data (e.g., corresponding to a specified number of samples, or counts, or a specified duration), then at state 2603 the system may perform a "dejitter" analysis to determine whether a foot is present. The de-jitter analysis may include signal smoothing, averaging, time delay or other processing, etc., to help distinguish signal noise from available foot presence information.

The debounce analysis may include monitoring the capacitance indication signal for changes and distinguishing a speed characteristic from the capacitance indication signal. In an example, the debounce analysis includes monitoring a speed characteristic to determine when the foot is partially or fully seated relative to a footbed of the footwear. When the capacitance indicating signal stabilizes to a substantially constant or steady state value, then the foot may be considered sufficiently seated so that the system may trigger one or more other functions of the automatic footwear, such as an automatic lacing function or a data collection function.

In the example of fig. 26, the debounce analysis includes "the capacitance sensing value is above the threshold and the slope is below the threshold". "the capacitance sensing value is above the threshold" indicates that the capacitance indication signal from the capacitive foot presence sensor records a value that exceeds the reference or baseline capacitance value. "slope below the threshold" indicates that the rate of change of the capacitance indicating signal from the sensor is less than a specified reference or baseline rate of change value, e.g., indicating that the foot is present in the footwear, but is substantially stationary relative to the sensor. When both conditions are met, an interrupt may be provided to one or more other processors or devices to trigger one or more other functions of the footwear. In an example, the interrupt includes a FOOT_INGRESS_EGRESS command in the footwear system state diagram 3100 of FIG. 31, as discussed below.

That is, from state 2603, the system may determine one of: (1) A non-zero sensor response indicates noise or timeout before a positive foot presence indication, and (2) a non-zero response indicates a valid foot presence signal. For (1), the system returns to state 2601 and resumes the low power monitoring state. For (2), the system continues to state 2604. Upon continuing to state 2604, the system verifies that the sensor response exceeds a specified threshold, and in some examples, the signal slope characteristic meets or exceeds a specified slope criterion. As shown in fig. 26, an interrupt determined based on the presence of the foot may be sent to one or more processors, circuits, or devices, for example, to initiate another activity or process when the presence of the foot is determined. For example, the interrupt may be used by the lacing engine to initiate an automatic lacing program or hardware process, such as in accordance with footwear system state diagram 3100 of fig. 31. At state 2604, the system remains in a state that includes a positive foot presence indication, and the system may be configured to wait for another signal or interrupt to initiate or conduct a subsequent process.

From state 2604, the system may enter a relatively low power or sleep state 2605, where the system may maintain further data or detected changes in the sensor signal. In an example, state 2605 represents a state in which the foot is present in the shoe and the shoe is actively in use or worn. For example, if the footwear is automatically laced and secured to the foot based on the foot presence determination from the debounce analysis at state 2603, the footwear may remain in a secured state around the foot at state 2605 while periodically monitoring the sensor state or waiting for another interrupt to change the state of the footwear. In an example, monitoring the capacitance indicating signal from the foot presence sensor at state 2605 includes monitoring the signal at a relatively low frequency, such as 1-2Hz or less, to identify whether the capacitance indicating signal has changed by more than a threshold amount.

In an example, from state 2605, if the signal indicates that the threshold amount of change is exceeded, the state machine proceeds to state 2606 where the foot presence indication interrupt may be cleared. In an example, continuing to state 2606 may include a hardware or software check to determine whether a baseline or reference characteristic of the sensor should be updated. For example, the symbol "HW Anti-touch Recal Threshold Passed" indicates an automatic recalibration process. If the foot is removed and in state 2606, the foot present signal indicative of capacitance is below a specified threshold, a new reference or baseline may be established. The new reference or baseline may be used for further detection activity, such as from state 2601. In an example, at state 2606, calibration or recalibration may be initiated each time the foot is removed from the footwear.

Various changes to the footwear itself, such as during use of the footwear, may result in the sensor signal indicating the presence of a foot, while in fact no foot is present in the footwear. For example, fluid saturation or wetness of one or more components of the footwear (e.g., due to perspiration) may affect the capacitive indication signal from the capacitive sensor and may affect the false indication that the foot is present in the footwear. Thus, at state 2605, the system may be configured to periodically wake up or conduct analysis and replenishment routines to verify whether the foot is present in the footwear.

In the example of fig. 26, the compensation routine may include timing data collection and analysis from the capacitive sensor. For example, after state 2605, the compensation routine at state 2607 may be triggered periodically or intermittently. In some examples, the compensation routine is performed every few minutes or hours. The compensation routine collects sensor signal data and monitors changes in the signal. If the signal includes a change that meets or exceeds a specified threshold change or amount of change, the system may determine that a foot may be present in the footwear and may maintain state 2605. The compensation routine may be repeated after a specified duration. However, if the sensor signal is relatively silent or unchanged for the monitored interval, the system may determine that there may be no foot present in the footwear and the system may return to state 2601. In this example, the return state 2601 includes recalibration to determine whether the baseline or reference capacitance indicator signal needs to be updated.

In an example, foot displacement information (e.g., relative to sensors inside the footwear) may be determined using count information from capacitive sensors in the footwear (e.g., foot presence sensor 310). The slope of the displacement information may be indicative of the speed characteristics of the foot within the footwear, and in turn, the speed of the footwear itself in some use cases. In an example, information regarding a speed characteristic of the foot may be used to trigger one or more characteristics of the footwear. For example, the speed profile may be used to identify an event of a footwear wear being unhooked, which in turn triggers an automatic lacing or unhooking procedure, respectively.

FIG. 26 illustrates different compensation and calibration techniques that may be used to manage the effects of user perspiration and changes in footwear material (e.g., compression and decompression), etc. For example, a user-initiated or commanded calibration may be used to recalibrate the footwear or reset the baseline capacitance value in response to user input. In an example, drift compensation may be used to occasionally adjust the baseline capacitance value. Drift compensation may be performed periodically or in response to a trigger (e.g., from another sensor), as discussed elsewhere herein.

In an example, fig. 26 illustrates a portion of a method for calibrating and operating a system in an article of active footwear that includes lacing engine 110. In the example of fig. 26, the foot presence sensor 310 may be a system input configured to receive user commands, such as foot presence or foot absence. In response to a user command, i.e., foot presence or absence, the foot presence sensor 310 may generate or provide a command signal that controls the operation of the lacing engine 110. In an example, the processor circuit 320 may provide instructions to the lacing engine based on characteristics or values of the command signals and the reference values. For example, the processor circuit 320 may provide instructions based on an amplitude difference between a value of the command signal and a reference value. In an example, the value of the command signal includes a capacitance or digital count, which represents the capacitance, as discussed elsewhere herein.

In an example, fig. 26 may include or use a state that includes receiving a calibration indication, such as [ CALIBRATE CAPSENSE ] in an example from state 2606 to state 2601. The calibration indication may include user instructions for calibration, or may be generated by or responsive to another portion of the footwear system. In response to receiving the calibration indication, the system may be configured to measure a value of a current indicated capacitance from the foot presence sensor 310 and update or change the reference value based on the measured current value. Thereafter, the state machine may use the changed reference value to determine the presence or absence of a foot, e.g., transition from state 2601 to 2602.

Fig. 27 generally shows an example of a graph showing foot presence sensor data. The example of fig. 27 includes a first curve 2701 (shown as a solid line) that indicates raw data sampled from a capacitive foot presence sensor. The example of fig. 27 also includes a second curve 2702 (shown as a short dashed line), which is a filtered version of the first curve 2701. In an example, the second curve 2702 is used for foot presence detection by comparing its amplitude to a specified threshold amplitude. For values of the second curve 2702 that exceed a specified threshold, the foot may be indicated as being present in the footwear, and for values of the second curve 2702 that do not exceed the specified threshold, the foot may be indicated as being absent from the footwear. The threshold and/or baseline capacitance values from the sensors may be updated or changed as discussed herein.

The example of fig. 27 includes a third curve 2703 (shown in long dashed lines). The third curve 2703 may indicate a slope of the first curve 2701, such as a slope of the first curve 2701 for a specified prior duration. The length of the previous duration may be adjusted based on the desired performance characteristics of the sensor or system (e.g., time of play or sensitivity, or immunity to noise or rapid signal changes or signal bounces).

In an example, the magnitude of third curve 2703 may indicate the relative speed of the footwear including the sensor, or the relative speed of the foot inside the footwear when the foot is wearing the footwear. The large amplitude of the third curve 2703 may correspond to a large velocity or displacement of the foot relative to the sensor in the vertical (z) and horizontal (x/y) directions, while the small amplitude of the third curve 2703 may correspond to a small velocity.

The example of fig. 27 also includes a fourth curve 2704 (shown as alternating short/long dashed lines). A fourth curve 2704 indicates whether the foot is present in the footwear. Thus, the fourth curve 2704 is a binary signal in the example of fig. 27, having two states, high and low.

In an example, information from the second curve 2702 and the third curve 2703 may be used (e.g., by a processor circuit) to determine whether a foot is present in the footwear. For example, if the signal information from the second curve 2702 is less than a specified threshold signal (e.g., less than 30 counts) followed by a detected change in speed, then the presence of a foot may be indicated. In an example, the detected speed change may be a speed change greater than a specified threshold speed amount. In another example, the detected speed change may include a speed profile comparison, such as comparing the speed change or waveform profile to a known speed change or profile corresponding to the presence of a foot.

In an example, the speed or displacement information of the footwear may be obtained from a separate sensor, such as an accelerometer or gyroscope mounted in or on the footwear. Such speed or displacement information may optionally be used with information regarding foot speed relative to sensors inside the footwear. For example, the foot speed information may be used to determine optimal footwear tension characteristics during use of the footwear (e.g., during athletic or activity). In an example, the foot speed information may be used to optimize the tension characteristics to a specified tightness, such as just tight enough to prevent relative movement (as detected by a capacitive sensor) between the foot and the footwear during a hard stop or sprint (as detected by an accelerometer or gyroscope). Conversely, if no foot or footwear speed or acceleration is detected, an excessive or unnecessary tension characteristic may be determined and the footwear tension may be relaxed. For example, if the foot swells during activity, the footwear may be loosened (e.g., the lace may be loosened) until some specified small speed is detected.

In examples, footwear incorporating an automatic lacing feature may be removed from the foot in a variety of ways in examples. For example, the footwear may include a button that the wearer may press to reduce tension in the lace, thereby making the footwear easier to remove. In some examples, a baseline or reference value of one or more sensors may change or update during use of the footwear (e.g., due to moisture remaining in the wearer's sock, or due to other environmental conditions). When a button is pressed, one or more sensors or baseline or reference values of the footwear may be reset or zeroed, for example, to facilitate subsequent foot presence sensing.

In another example, the footwear may be pried apart. The automatic lacing system described herein may detect when footwear is pried open, for example, by using a subthreshold count from a capacitive foot presence sensor to detect the absence of a foot. In an example, the absence of a foot may be detected in part using count information from a capacitive sensor as well as speed information indicative of a speed change and/or speed profile or morphology corresponding to a known shoe removal speed profile.

Fig. 28A-30D generally illustrate examples of a footbed assembly having a lacing engine assembly 2803, and various techniques or examples in a lacing engine cavity 2801 for installing or retaining the lacing engine assembly 2803 in the footbed. 28A, 29B, 29C, 30B, 30C, and 30D generally illustrate examples of a user accessing the lacing engine assembly 2803 and/or lacing engine cavity 2801 from the perspective of the user. The user's hand depicted in the figures is not required for any embodiment and does not form part of the present invention.

Fig. 28A and 28B generally illustrate an example of a footbed assembly with a backseat cover 2802. The footbed assembly may include a lacing engine cavity 2801, and a lacing engine assembly 2803 may be installed within the lacing engine cavity 2801. In the example of fig. 28A, the seat back cover 2802 is shown in a raised position to provide a view of the lacing engine cavity 2801 in which the lacing engine assembly is disposed. In fig. 28B, a seat back 2802 is mounted and covers substantially all of the lacing engine cavity 2801.

In an example, the lacing engine assembly 2803 can include electrodes of a capacitive sensor (see, e.g., examples of electrode assemblies in fig. 21A-21D, and other examples discussed herein). In an example, a dielectric member (e.g., neoprene or other closed or open cell rubber or foam, EVA or other material) can be disposed over the lacing engine assembly, and the seat back cover 2802 can be disposed over the dielectric member. In an example, the contour of the backseat cover 2802 may be set to the contour of the arch of the wearer's foot. In an example, the seat back cover 2802 is arcuate or umbrella-shaped to help divert moisture away from the lacing engine assembly 2803. The backseat cover 2802 may comprise various rigid or flexible materials, including carbon fiber, EVA, or neoprene, for example, and may be configured to be relatively conductive, thereby enhancing the body sensing sensitivity of the underlying capacitive sensor. Accordingly, the backseat cover 2802 may provide a protective cover for the lacing engine assembly 2803 and may enhance foot sensing capabilities in some examples.

Fig. 29A-29D generally illustrate an example of a footbed assembly having a first hook and loop cover for a lacing engine cavity 2801. The cover is disposed between the lacing engine assembly 2803 and the foot-receiving surface of the footwear. The cover provides various functions, such as retaining the lacing engine assembly 2803 in the lacing engine cavity 2801, and mechanically biasing one or more other materials in or near a portion of the dielectric stack above the lacing engine assembly 2803 to an uncompressed or decompressed state, particularly when the footwear is empty. In an example, the shackle cover provides a hanging mechanism that can be used to reduce pressure or decompress a dielectric stack disposed over the lacing engine assembly 2803. That is, the cover may bias the dielectric stack toward an uncompressed state.

In the example of fig. 29A, the first shackle cover includes a hook perimeter portion 2901 that follows the perimeter of the lacing engine cavity 2801 in the footbed. The outside edge of the hook perimeter portion 2901 may be secured to one or more edges of the lacing engine cavity 2801, and the inside edge of the hook perimeter portion 2901 may be flexible and manually raised to accommodate insertion of the lacing engine assembly 2803 into the cavity. The tie engine assembly 2803 may be covered with a loop material cover 2902. The loop material cover 2902 may help retain the lacing engine assembly 2803 inside the lacing engine cavity 2801 in the footwear. In some examples, loop material cover 2902 includes a hydrophobic, outwardly facing side and is configured to assist in diverting moisture away from the lacing engine.

30A-30D generally illustrate an example of a footbed assembly having a second hook and loop cover for a lacing engine assembly. In the example of fig. 30A, hook and loop material covers 3001 and 3002 cover lacing engine cavity 2801 in the footbed. In fig. 30B, the hook cover 3001 follows a first side edge of the lacing engine cavity 2801 in the footbed. The side edges of the hook material cover 3001 may be coupled to the footbed on a first side of the lacing engine cavity 2801 and may be flexible and manually raised to accommodate insertion of the lacing engine assembly 2803 into the lacing engine cavity 2801 (see, e.g., fig. 30C). A side edge of the loop material cover 3002 may be coupled to the footbed at a second, opposite side of the lacing engine cavity 2801 such that the hook and loop material covers 3001 and 3002 at least partially overlap and couple with each other.

One or more components of the dielectric stack 3004 may be disposed near or on a portion of the lacing engine assembly 2803. In the example of fig. 30D, the dielectric stack 3004 includes a neoprene or doped EVA layer disposed adjacent to the electrode assembly inside the housing of the lacing engine assembly 2803. The lacing engine assembly 2803 with the dielectric stack 3004 may be covered with hook and loop material covers 3001 and 3002 as shown in fig. 30A. The hook and loop material covers 3001 and 3002 may be configured to retain the lacing engine assembly 2803 inside the lacing engine cavity 2801 in the footbed. In some examples, the upper one of the hook and loop material covers 3001 and 3002 includes an outer (foot facing) side that is hydrophobic and configured to assist in transferring moisture away from the lacing engine assembly 2803.

In the example of fig. 30D, the dielectric stack 3004 overlies a portion of the housing of the lacing engine assembly 2803. A gap filler (e.g., polyurethane or other foam or compressible member) may be inserted to cover the remainder or other portion of the housing, for example, to provide a relatively seamless and comfortable underfoot surface for the user. The gap filler may be substantially transparent to the electric field monitored by the capacitive foot presence sensor in the lacing engine assembly 2803. In other words, the gap filler material may be selected to minimize impact or impact on the signal indicative of foot presence from a capacitive foot presence sensor in the lacing engine assembly 2803 or coupled to the lacing engine assembly 2803.

The shackle assembly in the examples of fig. 29A-29D and 30A-30D may be configured to help absorb and distribute foot impact forces, e.g., away from the lacing engine assembly 2803, and also be substantially transparent to the fields used by capacitive sensors inside (or near) the lacing engine assembly 2803 to monitor or detect whether the foot is present in the footwear. In an example, the various shackle components or backseat covers discussed herein may be configured to provide an outward or upward mechanical bias away from the dielectric stack 3004, thereby reducing the effects of repeated compression of the dielectric stack 3004 due to footwear use, thereby maintaining foot presence sensing signal sensitivity, fidelity, and dynamic range during repeated or prolonged use of the footwear.

Fig. 31 generally illustrates an example of a footwear system state machine 3100. The footwear system state machine 3100 may be implemented, for example, using the processor circuit 320, the processor circuit 320 in data or power signal communication with one or more of the following: interface button 301, foot presence sensor 310, battery 321, charging coil 322, and drive mechanism 340, as well as other components of the active footwear system. The example of FIG. 31 illustrates how components may provide instructions to or receive information from a motor, button, battery, foot presence sensor 310, or other component of the footwear system. In the figure, circles represent different states, including state arming (state [0 ]), state waiting standing (state [1 ]), state unbinding (state [2 ]), and state in motion (state [3 ]).

In the example of FIG. 31, each transition between states is annotated with PRECCONDITION/EVENT/[ ACTION ]. The PRECONDITION indicates a requirement or PRECONDITION for a change from a particular state. For example, the PRECONDUCTION from state [0] to state [1] may include the system motor having a minimum threshold charge (BATT_OK) and the & &. The lacing engine 110 being in the original or unwound shaft position (AT-HOME) such that the footwear lacing is loosened and not tied. A minimum threshold charge limit may be imposed to ensure that the system has sufficient battery life remaining to unwind the spool after the spool action.

Referring again to the example of a change from state [0] to state [1], EVENT may include FOOT entering or exiting footwear (foot_ingess_egress), such as may be detected using FOOT presence sensor 310. In an example, a foot_ingess_address event may include receiving a signal from a FOOT presence sensor state machine, such as described above in the example of fig. 26.

Returning again to the change from state [0] to state [1], the [ ACTION ] may include starting or starting a TIMER or sampler (START ACCEL _sample_timer) to monitor information from the motion sensor 324 (which may include an accelerometer, for example). In an example, information from the motion sensor 324 may be used to confirm the orientation of the footwear and/or the presence of the foot prior to initiating the lacing action.

In the example of fig. 31, EVEN including ARM may be a user input to the state machine. For example, ARM may be asserted in response to a button press using one or more interface buttons 301, may be asserted in response to an input to a mobile device in communication with processor circuit 320, or may be asserted in response to an input to another interface in communication with processor circuit 320. In an example, ARM can be asserted in response to a signal from a capacitive touch sensor or capacitive interface 3500 discussed below. In an example, ARM may instruct a user to unwind a reel or loosen footwear so that the footwear may be removed from the foot. In an example, the unwound state is referred to herein as the home position of the spool or motor of the drive mechanism 340 that controls the lace.

In the example of fig. 31, the EVENT including the lace may be a state or condition in which the footwear lace is wound or tightened. That is, the LACED event may include a condition in which the drive mechanism 340 is or has been activated and the lace is wound away from the home position. The EVENT including the AUTOLACE may be a command or order to operate the drive mechanism 340 to spool the lace to a preset position, such as a specified amount of tightness or tension of the footwear in the lace.

In the example of fig. 31, [ ACTION ] including [ cs_rest ] may include a command that may trigger or initiate a calibration event of the foot presence sensor 310. For example, [ CS_RESTART ] may be asserted when the footwear transitions from state [3] motion. That is, the footwear may be configured to recalibrate the reference condition of the foot presence sensor 310 each time the footwear is removed or removed. In an example, the footwear may be configured to recalibrate the reference condition of the foot presence sensor 310 when the footwear is removed after unbinding or unwinding, or the footwear may be configured to recalibrate the reference condition of the foot presence sensor 310 when the footwear is removed by brul force (e.g., by pulling the footwear off the foot while the lace is still tensioned or wound).

In the example of FIG. 31, [ ACTION ] including DISABLE_SENSOR may include disabling processor circuit 320 from receiving or using the FOOT_INGRESS_EGRESS instruction from the FOOT presence SENSOR state machine of FIG. 26. When the footwear is confident that the foot is in the footwear, and the lacing system is wound or tensioned to hold the foot inside the footwear, such as in state [3], the processor circuit 320 may be inhibited from receiving further instructions from the foot presence sensor 310. In other words, in the in-motion state, or in state [3] of the example of fig. 31, after the system responds to a positive identification that the foot from foot presence sensor 310 is present in the footwear, the system may cease to monitor for commands or interrupts from foot presence sensor 310. In an example, another user command in addition to the presence of the foot may be used to unwind the reel or release the lace and remove the footwear, for example using an ARM command. ARM commands may be declared in various ways, such as from a detected footwear gesture, pressing a button, or by instructions received from a different wired or wireless interface.

In an example, the foot presence sensor 310 is configured to generate an electric field as described above, and to identify or sense a change in the electric field. In an example, the foot presence sensor 310 identifies the electric field change as a change in the capacitance value measured by the sensor.

In an example, the electric field emanating from the electrodes of the foot presence sensor 310 terminates at the ground plane of the PCA (see, e.g., examples and discussion of fig. 5A, 5B, and 6). However, the sensor signal path of interest may be substantially in the opposite direction, e.g. towards the foot or other body to be sensed. In an example, such as shown in fig. 5A, 5B, and/or 6, the sensor or electric field signal path of interest may be substantially through a cushioning material or insole, such as insert material 510, toward the foot or body to be tested, and then may be returned to the sensor or PCA. Another potential or field path may exist more directly between the electrode(s) of the sensor and the PC a, for example through the housing structure 150 including the lacing engine 110 and the PCA.

Various potential or field paths may introduce ground effects, i.e., unless mitigated, may result in erroneous readings of the foot presence sensor 310. For example, the field path may extend from the electrode(s) of foot presence sensor 310 through the outsole and then back to the PCA. In examples where lacing engine 110 and electrodes are disposed under the foot, the field path may extend laterally or laterally outward from the bottom of the footwear, toward the ground, and then return to the PCA in an upward direction. In other words, additional field paths may exist in a direction opposite to the target sensing direction of the sensor. In examples where the electrodes and PCA are disposed under the foot, such parasitic fields on the exterior of the footwear may interact with the environment, such as with the floor, or with the hand when the footwear is grasped around the bottom or arch region of the footwear. Depending on the footwear material, parasitic fields may affect the capacitance measured by foot presence sensor 310. In an example, the parasitic field may cause a change in sensor capacitance that is greater than the lowest signal capacitance generated by some positive signals (e.g., the foot in footwear). Further, parasitic fields may lead to false foot presence detection events and may lead to abnormal or unpredictable lacing engine triggers or behavior.

In an example, the magnitude of the ground effect, or parasitic field, may be substantially proportional to the sensitivity of the capacitive foot presence sensor 310, such as when the sensor includes or uses a planar electrode assembly configuration, such as those shown in the examples of fig. 21A-21D. In examples, other electrode configurations may include or use peripheral ground traces to shape the generated field and thereby minimize unwanted or parasitic field paths (e.g., through the outsole), and may instead concentrate the sensor field in a particular direction or region. In an example, other adjustments to the field or field focus may be made by adjusting the shape or material characteristics of a dielectric stack (e.g., dielectric stack 3004) used with foot presence sensor 310.

In an example, adverse ground effects may be identified by analyzing the output signal from the foot presence sensor 310, and such adverse ground effects may be mitigated with the processor-implemented response. For example, various algorithms may be used to distinguish ground effect events from actual foot presence or footwear wear events, such as using capacitance indication signals from foot presence sensor 310, using information from motion sensor 324, or using other techniques.

In an example, information from the signal of foot presence sensor 310 may be used to distinguish a donning event from adverse ground effects or parasitic fields. For example, information about the sensor signal amplitude and/or about the sensor signal rise time may be used.

Fig. 32 generally illustrates a graph 3200 that shows values of a first foot presence sensor signal 3201 over time and includes a footwear donning event. The example of fig. 32 includes a first foot presence indicator signal 3202 that transitions from a low state to a high state. A high state indicates that the foot is present in the footwear, while a low state indicates that the foot is not present. In an example, the value of the first foot presence indicator signal 3202 corresponds to the value of the interrupt signal in the various state diagrams discussed herein.

In the example of fig. 32, the donning event begins at approximately sample number 1100 with a brief period of noise while the user moves the footwear and positions the footwear prior to donning. Foot insertion and detection of foot presence sensor 310 occurs at about sample 1300 as represented by a significant rise in first foot presence sensor signal 3201 from a normalized baseline value of about zero to about 140 units or counts. As explained elsewhere herein, the count may correspond to an output of a capacitive foot presence sensor. For example, the count may correspond to a digital signal from an analog-to-digital converter that receives an analog output from a capacitive sensor (e.g., foot presence sensor 310).

In the example of fig. 32, the donning event occurs within about 170 samples (about 3 seconds) as the user places the foot inside the footwear and seats the foot against the footbed or sole of the footwear. By about sample 1430, the first foot presence sensor signal 3201 may be considered sufficiently stable and the first foot presence indicator signal 3202 changes state. In an example, an interrupt signal, such as the base_inhibit_address from the example of fig. 31, may be generated or asserted based on the state of the first FOOT presence indicator signal 3202.

Fig. 33 generally illustrates a graph 3300 that shows the value of the second foot presence sensor signal 3301 over time. The example of fig. 33 includes the ground effect without the footwear being worn. The example of fig. 33 includes a second foot presence indicator signal 3302 that transitions from a low state to a high state. A high state indicates that the foot is present in the footwear, while a low state indicates that the foot is not present.

In the example of fig. 33, the ground event begins at about sample 410. The ground event is detected by the foot presence sensor 310 and results in a rise in the second foot presence sensor signal 3301 from a normalized baseline value of about zero to about 80 units or counts. In the example of fig. 33, the ground event causes the second foot presence sensor signal 3301 to reach a substantially steady state within about 81 samples (or less than 2 seconds). Accordingly, the second FOOT presence indicator signal 3302 changes state at about sample 490 and may generate an interrupt signal, such as the foot_ingess_egress from the example of fig. 31.

From the example of fig. 32, the time for which the shoe in-wear and foot presence sensor 310 records a substantially steady state output may be approximately 3 seconds. In contrast, from the example of fig. 33, an example in which the foot presence sensor 310 records a substantially steady state output may be less than two seconds if a ground event occurs. In addition, in the examples of fig. 32 and 33, the peak and stability of the first foot presence sensor signal 3201 and the second foot presence sensor signal 3301 may be different. For example, the first foot presence sensor signal 3201 reaches a peak amplitude of about 160 counts and a steady state amplitude of about 140 counts. The second foot presence sensor signal 3301 reaches a peak magnitude of 80 counts and a substantially similar steady state magnitude of about 80 counts. Thus, in examples including foot entry, the toes and foot slide over the sensor electrodes until the foot is seated in the footwear and conversion takes about 170 samples or three seconds, from initial wear to full seating and stabilization, and the corresponding sensor signal may have an amplitude of about 140-160 counts. In examples including a ground event, on the other hand, the signal rises about 81 samples, less than two seconds, from start-up to interrupt generation, and the amplitude of the corresponding sensor signal is about 80 counts.

The foot presence sensor signal timing and amplitude may be analyzed for multiple samples, for example, to identify trends. Fig. 34 generally shows a scatter plot showing the relationship between wear duration and foot presence sensor signal amplitude. The example of fig. 34 includes a chart 3400 that represents 51 wear events from 25 different individuals. In an example, the timing begins with a previous transition of the foot presence sensor signal above a sensing threshold and ends with generation of an interrupt (e.g., at sensor signal steady state). In an example, before issuing the interrupt, the amplitude is averaged over a data window comprising 12 samples. This averaging corresponds to, for example, 140 counts in fig. 32 and 80 counts in the example of fig. 33.

In the example of fig. 34, a single ground effect sample is shown as an open circle and a non-ground effect sample is shown as a solid dot. Ground effect samples represent a relatively short duration and low amplitude compared to other samples. In an example, to determine the unique degree of the ground effect sample, a normal distribution may be assumed, and an average value and a standard deviation value may be calculated. In the example of fig. 34, the vertical axis is set at a time corresponding to the average value minus one standard deviation, or at 100 samples (2 seconds). The horizontal axis is at an amplitude corresponding to the average amplitude minus one standard deviation. The coordinate axis divides the chart 3400 into quadrants labeled I, II, III, and IV. In the example of fig. 34, the ground effect sample is the only sample in quadrant III.

In view of the example of fig. 34, subsequent foot sensor signal information may be received from the foot presence sensor 310 and processed to identify wear time and amplitude. Subsequent foot sensor signal information may be sampled and analyzed using the chart 3400 to determine whether the signal includes a ground effect type error or includes a legitimate signal (e.g., due to the foot entering the footwear).

In an example, ground effect time identification may be performed using the footwear system state machine 3100. In an example, a ground effect time identification algorithm or analysis may be performed during state [1 ]. For example, in state [1], information from motion sensor 324 may be received and analyzed to determine an orientation of the footwear. Further, in state [1], the system may analyze the capacitance indication signal from the foot presence sensor 310 to identify amplitude characteristics and rise time characteristics, and may plot or compare the characteristics against the coordinate axes provided in the example of FIG. 34. If the rich deterioration rise time characteristic places the sample in quadrant III, the footwear system state machine 3100 may return to state 0, for example, by issuing CS_RESTART. The s_restart command may remove (tare out) the parasitic field and may abort the strapping command.

In an example, the calculation of the wear time and average amplitude may be performed during state [1], and the calculated value may be stored in a register or buffer circuit of the sensor controller. When production is interrupted, the footwear system state machine 3100 may read the stored values and determine subsequent actions. For example, if the time and amplitude characteristics place the sample in quadrant I, II or IV, the logical response to ground effect identification may be false. However, if the characteristic places the sample in quadrant III, the logical response may be true. The ground effect result (e.g., true or false) may be combined (e.g., via logical AND) with information from the motion sensor 324 to determine a condition to advance to state [2] or return to state [0 ].

In an example, one or more interface buttons 301 from the example of fig. 3 may be provided using a capacitance-based input device or touch sensor. The touch sensor may be disposed on the housing structure 150 or attached to the housing structure 150 and coupled to circuitry therein, or the touch sensor may be remote from the housing structure 150 and coupled to circuitry internal to the housing structure 150 using electrical conduction. For example, the touch sensor may be disposed on a tongue, outsole, toe area, heel area, or elsewhere on the footwear. In an example, a capacitive touch sensor may be disposed on or in the housing structure 150 and an interface disposed on another surface of the footwear and an actuation device is provided to couple the interface with the touch sensor. The actuation device may electrically couple the interface to the touch sensor.

In an example, a capacitance-based input device or touch sensor may include a capacitive interface, for example, may include a capacitive strip having one or more conductors or electrodes. Fig. 35 generally illustrates a perspective view of an example of a housing structure 150 with a first capacitive interface 3500 disposed on a first side of the housing structure 150. Fig. 36 generally illustrates a side view of a portion of housing structure 150 that includes capacitive interface 3500. Capacitive interface 3500 includes a first electrode 3501 and a second electrode 3502.

For example, the electrodes may be substantially flat planar structures, or may be curved structures, such as may conform to a sidewall, support, sole, tongue, or other portion of an article of footwear. In examples, one or more of the electrodes may include a flexible conductive material, such as a film, conductive polymer or fiber, or other material. The electrodes may comprise a material deposited on or integrated with a flexible or rigid substrate material (e.g., a fabric or polymer substrate).

In an example, the first electrode 3501 and the second electrode 3502 can be electrically isolated from each other. That is, the first electrode 3501 and the second electrode 3502 may be spaced apart, e.g., at least a fixed distance. The electrodes may be spaced apart a distance small enough that the electrodes may be bridged or shunted by the distal portion of the fingertip or finger. In other words, the electrodes may be spaced apart such that a user's finger (or other body part) may contact both the first electrode 3501 and the second electrode 3502 when the fingertip is against the capacitive interface 3500.

In an example, the first electrode 3501 and the second electrode 3502 of the capacitive interface 3500 can have similar or different shapes. In an example, as shown, the first electrode 3501 and the second electrode 3502 are triangular structures having similar sizes and shapes. In an example, the triangular structures may be formed or provided by rectangular structures that are cut or split into two right triangle structures along one of their diagonals, which are then spaced apart along their respective hypotenuses or oblique sides. In an example, different shaped conductive structures may be used together. For example, a triangular structure may be used with a rectangular structure.

In an example, the electrodes may be rectangular structures, which may have similar or different sizes, for example in terms of length or area. In an example, the electrodes may be offset from each other in the lateral direction such that one electrode extends away from a side edge of the other electrode. In this example, the user may contact a portion of one electrode without contacting the other electrode. In an example, the first electrode 3501 and the second electrode 3502 may be configured in mirror image of each other in shape. The examples of fig. 35-39 generally illustrate touch sensors having two electrodes, however, additional electrodes may similarly be used, for example, for further control or granularity. For example, three or more elongated rectangular structures may be provided and may optionally be offset in the lateral direction such that a fingertip may contact one, two or three (or more) of the structures depending on the position of the fingertip.

In an example, the first electrode 3501 and the second electrode 3502 can have different conductive properties. For example, the first electrode 3501 may include or be made of a first material having a first conductive characteristic, and the second electrode 3502 may include or be made of a second material having a second, different conductive characteristic.

The first electrode 3501 and the second electrode 3502 may be coupled to a drive circuit inside the housing structure 150 or elsewhere. The drive circuit, which may include, for example, a processor circuit, signal generator, or other circuit, may periodically or intermittently poll or measure capacitance from the electrodes to identify changes in capacitance, for example, may indicate user input or instructions to the processor circuit 320. In an example, the drive circuit is configured to provide an AC drive signal to the first electrode 3501 and the second electrode 3502 and to measure a response from the same electrode. Based on the response, a capacitance or capacitance indication signal may be measured.

The capacitance measured from the electrodes may be affected or altered by the user's body at, near or beside the electrodes, and may further be affected or altered by the position of the user's body relative to the electrodes. In an example, a baseline or reference capacitance may be measured, for example, when the user does not touch an electrode, or when the user touches a designated reference portion of the interface.

In an example, capacitive interface 3500 is configured to map to different settings or tightness characteristics of the automatic lacing system. The map may, for example, include a user input or "swipe" area that may be used to adjust the lace state of the lace spool characteristics, for example, in response to a user dragging a finger over a portion of the interface. In an example, capacitive interface 3500 may additionally or alternatively be configured to be responsive to a "touch" input, such as a momentary finger press at one or more locations on the surface of capacitive interface 3500. The speed, position, force, or other characteristics of the user input to the interface may be used by the system or interpreted as a different input.

For example, fig. 37 generally illustrates an example of a relationship 3700 between the location of an input body 3701 and a capacitive signal 3703 (e.g., may be received from a capacitive interface 3500). In an example, as the position of input body 3701 moves from left to right across capacitive interface 3500, the magnitude of the first signal from first electrode 3501 may decrease, e.g., corresponding to a contact area between input body 3701 and a portion of first electrode 3501. That is, when the input body 3701 is located at the leftmost side of the first electrode 3501, the input body 3701 contacts a larger surface area of the first electrode 3501 than when the input body 3701 is located at the rightmost side of the first electrode 3501. In the example of fig. 37, when the input body 3701 is located on the far right side of the first electrode 3501, the touch sensor or capacitive interface 3500 records or measures the minimum capacitance indicated by the capacitance signal 3703. Conversely, the example shows that when the same input body 3701 moves from left to right, an increased second signal may be provided by contact with the second electrode 3502, which in turn may correspond to the decreased second capacitance signal 3702.

In an example, information from one or more electrodes of capacitive interface 3500 may be used to determine a spool position based on the position of input body 3701. For example, fig. 38 generally illustrates an example 3800 of a relationship between the position of an input body 3701 and a spool position 3801. In example 3800, spool position 3801 may correspond to a de-spool or release configuration when input body 3701 is to the left of capacitive interface 3500. When the input body 3701 is to the right of the capacitive interface 3500, the spool position 3801 may correspond to a fully wound or tightened configuration. The neutral position of the input body 3701 may correspond to the neutral spool and corresponding tightness of the footwear.

Fig. 39 generally illustrates an example 3900 of a relationship between an input gesture at capacitive interface 3500 and spool position 3901. In example 3900, when input body 3701 provides an input gesture, such as a swipe, from left to right in fig. 1, lacing engine 110 may be configured to spool or tighten footwear by a specified first amount. The second scan may cause the lacing engine 110 to further spool or tighten, and so on, until the maximum tightness characteristic is achieved. In an example, sliding in the opposite direction may cause the lacing engine 110 to reduce tightness, e.g., by a discrete amount, or a single right-to-left sliding may be used to completely unwind the spool or return the lacing engine 110 to the original position, for example. Thus, a rolling input action of the input body 3701 at the capacitive interface 3500 may initiate a similar "rolling" spool or unwind shaft at the lacing engine 110. In an example, the sensitivity of the scroll input or spool response may be adjustable or may be related to the speed at which the input body 3701 moves through the capacitive interface 3500.

In an example, capacitive interface 3500 includes or includes a touch sensor for use with a footwear system. The touch sensor can include a first electrode 3501 and a second electrode 3502, which can include, for example, elongated electrodes or conductive structures that are substantially adjacent and spaced apart along a first length or width of the sensor. The first electrode 3501 and the second electrode 3502 may be configured to receive a user body input via contact between the user body and the electrodes to electrically shunt the electrodes. For example, the electrodes may be disposed close enough to each other that a user's finger or fingertip may electrically or capacitively bridge the electrodes to affect the measured or sensed electrical characteristics between the electrodes.

The touch sensor may be configured to receive user body input at different locations along a first length of the sensor at different times and, in response, provide respective corresponding sensor signal values indicative of the location of the user body input. For example, when a user body input is provided at a first location on the sensor, the surface area of the first electrode contacted by the user body input is greater than the second electrode, and as a result, a first electrical characteristic or signal value may be measured. When a user body input is provided at a different, second location on the sensor, the surface area of the first electrode contacted by the user body input is smaller than the second electrode, as a result of which a second electrical characteristic or signal value can be measured. The first and second electrical characteristics or signal values may be used to distinguish or identify a relative or absolute position of the user input with respect to the touch sensor interface, thereby controlling one or more aspects of the footwear system.

Attention matters and aspects

Aspects of the present disclosure may help provide a solution to the problems identified herein that are related to an active footwear interface.

In examples, aspect 1 may include or use a subject matter such as a device, system, or apparatus, which may include or use a method for calibrating or operating one or more systems in an article of active footwear. In an example, aspect 1 may include an active footwear having a lacing engine configured to tighten or loosen the footwear in response to a user command at a user input, wherein the user command sets or provides a command signal that controls operation of the lacing engine based on a relationship between a command signal value and a reference value. In an example, aspect 1 may include the steps of: for example, a calibration indication is received, and in response to receiving the calibration indication, a current value of the command signal is measured and an updated reference value is provided based on the current value of the command signal, and a subsequent user command at the user input is received, and in response, a subsequent value of the command signal is measured. Aspect 1 may also include controlling the lacing engine based on a relationship between a subsequent value of the command signal and the updated reference value.

Aspect 2 may include or be used, or may optionally be combined with the subject matter of aspect 1, to optionally include receiving a user command or receiving a subsequent user command, including receiving information regarding the presence of a user's body at a sensor coupled to the active footwear.

Aspect 3 may include or be used, or may optionally be combined with the subject matter of aspect 2, to optionally include receiving information regarding the presence of a user's body, including receiving information regarding the presence of a foot inside the active footwear.

Aspect 4 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 1-3, to optionally include or use receiving a user command or receiving a subsequent user command, including receiving information regarding the proximity of the foot to a foot presence sensor inside the active article of footwear.

Aspect 5 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 1-4, to optionally include controlling the lacing engine based on a relationship between a subsequent value of the command signal and the updated reference value, including determining an amplitude difference between the subsequent value of the command signal and the updated reference value, the lacing engine being controllable based on the amplitude difference.

Aspect 6 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 1-5, to optionally include receiving a calibration indication, including receiving the calibration indication from a user via a hardware interface coupled to the lacing engine or via a software interface in a remote device in data communication with the lacing engine.

Aspect 7 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 1-6, to optionally include receiving a calibration indication from a processor circuit, wherein the processor circuit is configured to provide the calibration indication periodically or according to a specified calibration schedule.

Aspect 8 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 1-7, to optionally include receiving a calibration indication from a processor circuit, wherein the processor circuit is configured to provide the calibration indication in response to a detected change in moisture content of the active footwear.

Aspect 9 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 1-8, to optionally include receiving a calibration indication from a processor circuit, wherein the processor circuit is configured to provide the calibration indication in response to a detected user mode of the active footwear.

Aspect 10 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 1-9, to optionally include receiving a calibration indication from a processor circuit, wherein the processor circuit is configured to provide the calibration indication in response to compression or expansion of a structural component of the active footwear.

Aspect 11 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 1-10, to optionally include receiving a calibration indication from a processor circuit, wherein the processor circuit is configured to provide the calibration indication in response to a detected presence of a user's body inside the active footwear when the footwear is relaxed or unrestricted.

Aspect 12 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 1-11, to optionally include updating the reference value, including setting the updated reference value to the same value as the measured current value of the command signal.

Aspect 13 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 1-12, to optionally include measuring a current value of the command signal, including measuring a capacitance value from a capacitive sensor in the active footwear, wherein the capacitive sensor provides the command signal based on a detected presence, absence, or proximity to the sensor of the user's body.

Aspect 14 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 1-13, to optionally include receiving a calibration indication from a user input via a capacitive touch sensor, wherein the capacitive touch sensor includes a plurality of electrodes and is configured to detect a location of the user input on a surface of the sensor.

In examples, aspect 15 may include or use a theme such as a device, system, or apparatus, which may include an article of active footwear. Aspect 15 may include a user input configured to receive a user command and in response provide a command signal representative of the user command, and a lacing engine configured to tighten or loosen the footwear based on a relationship between a value of the command signal and a reference value, and a processor circuit. The processor circuit may be configured to receive the calibration indication and, in response to the received calibration indication, measure a current value of the command signal and provide an updated reference value based on the current value of the command signal, receive a subsequent user command at the user input, and in response, measure a subsequent value of the command signal and control the lacing engine based on a relationship between the subsequent value of the command signal and the updated reference value.

Aspect 16 may include or be used, or may optionally be combined with the subject matter of aspect 15, to optionally include user input, including a sensor configured to detect the presence or absence of a user's body in proximity to the sensor.

Aspect 17 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 15 or 16, to optionally include user input, including a capacitive foot presence sensor configured to detect the presence or absence of a user's foot inside the footwear.

Aspect 18 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 15-17, to optionally include or use a processor circuit to control the lacing engine based on a difference in amplitude between a subsequent value of the command signal and the updated reference value.

Aspect 19 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 15-18, to optionally include or use processor circuitry to receive a calibration indication from one or more of: a hardware interface coupled to the lacing engine, a software interface in a remote device in data communication with the lacing engine, a clock circuit configured to provide a calibration indication periodically or according to a specified calibration schedule, a moisture sensor configured to provide a calibration indication in response to a change in moisture content in the footwear, an activity sensor configured to provide a calibration indication in response to a detected user mode in the active footwear, and a material sensor configured to provide a calibration indication in response to a detected compression or expansion of a structural component of the active footwear.

In examples, aspects 20 may include or use a subject matter such as a device, system, or apparatus, which may include a method for avoiding false triggering from a capacitive sensor of an article of footwear, wherein the capacitive sensor is configured to generate a footwear control signal based on the presence, absence, or proximity to the capacitive sensor of a user's body. In aspect 20, the method may include generating, by the capacitive sensor, a footwear control signal based on the presence, absence, or proximity to the capacitive sensor of the user's body over time, determining correspondence between a specified sensor behavior model and one or more of: the amplitude characteristic, the morphology characteristic, or the rate of change characteristic of the footwear control signal, and disabling or enabling the automatic lacing or unbinding function of the footwear based on the determined correspondence.

Aspect 21 may include or be used, or may optionally be combined with the subject matter of aspect 20, to optionally determine correspondence, including determining whether the footwear control signal includes more than a specified minimum rate of change and less than a specified maximum amplitude for a first duration.

Aspect 22 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 20 or 21, to optionally include receiving footwear orientation information from an accelerometer coupled to the article of footwear, and disabling or enabling automatic lacing or unbinding functions of the footwear may be based on the footwear orientation information and the determined correspondence.

Aspect 23 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 20-22, to optionally include providing a specified sensor behavior model based on information about a user-specific footwear donning or footwear doffing event.

Aspect 24 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 20-23, to optionally include generating the footwear control signal based on the presence of a user's body external to the footwear and in proximity to the sensor.

In examples, aspect 25 may include or use a theme such as a device, system, or apparatus that may include or use an interface system for footwear, e.g., may optionally be provided alone in combination with the theme of one or any combination of aspects 1-24. In an example, aspect 25 may include an interface system for an active article of footwear, and the interface system may include at least a touch sensor including two or more electrodes spaced apart and configured to receive user touch input bridging at least two electrodes, and the sensor may be configured to receive user touch input at a plurality of locations along a length of the sensor. Aspect 25 may include measurement circuitry configured to measure capacitance indication signals from two or more electrodes, and the capacitance indication signals may include information regarding the location of a user touch input on the sensor.

Aspect 26 may include or use, or may optionally be combined with the subject matter of aspect 25, to optionally include or use a processor circuit configured to receive the capacitance indication signal and, in response, to provide a corresponding control signal to a lacing engine of the article of active footwear to tighten or loosen the article of active footwear.

Aspect 27 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 25 or 26, to optionally include or use a processor circuit configured to receive the capacitance indication signal and, in response, calibrate a foot position sensor of the active article of footwear.

Aspect 28 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 25-27, to optionally include two or more electrodes of a touch sensor that include spaced apart substantially planar electrodes.

Aspect 29 may include or be used, or may optionally be combined with the subject matter of aspect 28, to optionally include substantially planar electrodes that are similar in size and have a right triangle shape. In aspect 29, the electrodes may be disposed adjacent to each other along all or a portion of their respective hypotenuses.

Aspect 30 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 25-29, to optionally include at least two of the electrodes having different conductive properties.

Aspect 31 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 25-30, to optionally include or use, as at least two electrodes, respective flexible conductors disposed on a flexible substrate.

Aspect 32 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 25-31, to optionally include or use a measurement circuit to measure a change in capacitance indication signals from at least two electrodes, and the change is indicative of a gesture or movement of a user touch input along or adjacent to the touch sensor.

Aspect 33 may include or be used, or may optionally be combined with the subject matter of aspect 32, to optionally include a change in the capacitance indication signal that indicates a user's swipe gesture along the length of the sensor.

Aspect 34 may include or be used, or may optionally be combined with the subject matter of aspect 32, to optionally include a measurement circuit configured to measure a rate of change of the capacitance indicating signal, and the rate of change indicates an amplitude of the desired change in the tightness of the footwear.

Aspect 35 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 25-34, to optionally include the location of the user touch input on the sensor corresponding to a desired magnitude of increase or decrease in the tightness characteristic of the footwear.

Aspect 36 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 25-35, to optionally include at least two electrodes that are fixedly spaced apart, and the user touch input electrically couples or shunts the at least two electrodes using a portion of the user's body. In other words, the portion of the user's body (e.g., a finger or fingertip) may be used to electrically couple the electrodes together.

In an example, aspects 37 may include or use a theme such as a device, system, or apparatus, which may include or use a footwear system, including: a lacing engine configured to tighten or loosen the article of footwear in response to the control signal; a processor circuit configured to generate a control signal; a housing configured to enclose at least a portion of the lacing engine and the processor circuit; and a touch sensor comprising two or more electrodes, a sensor communicatively coupled with the processor circuit and configured to receive user input, wherein the user input electrically couples the two or more electrodes via the user's body. In aspect 37, the processor circuit may be configured to generate the control signal based on user input.

Aspect 38 may include or use, or may optionally be combined with the subject matter of aspect 37, to optionally include two or more electrodes as respective elongated substantially planar structures disposed at least partially adjacent to each other and spaced apart from each other.

Aspect 39 may comprise or be used, or may optionally be combined with the subject matter of aspect 38, to optionally comprise a processor circuit configured to generate control signals based on a user input to the location of the touch sensor.

Aspect 40 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 37-39, to optionally include a processor circuit configured to initiate a foot sensor calibration procedure in response to user input.

Aspect 41 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 37-40, to optionally include two or more electrodes as substantially planar electrodes having similar sizes and triangular shapes.

Aspect 42 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 37-41, to optionally include two or more electrodes having respective different conductive properties.

Aspect 43 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 37-42, to optionally include touch sensors disposed at one or more of a tongue, outsole, toe area, or heel area of the article of footwear, and the touch sensors may be electrically coupled to the processor circuit.

Aspect 44 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 37-43, to optionally include a touch sensor coupled to a side wall of the housing.

Aspect 45 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 37-44, to optionally include two or more electrodes as flexible electrodes disposed on a flexible substrate.

Aspect 46 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 37-45, to optionally include a touch sensor including a capacitive sensor configured to measure capacitance between two or more electrodes, and the magnitude of the capacitance varies according to user input.

Aspect 47 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 37-46, to optionally include a touch sensor configured to receive user input, including a swipe gesture that electrically couples two or more electrodes through a section or length of the sensor using the user's body.

In an example, aspects 48 may include or use a theme such as a device, system, or apparatus that may include or use a user interface for controlling a footwear system. In an example, aspect 48 includes a capacitive user interface for controlling a footwear system. Aspect 48 may include a touch sensor comprising first and second elongate electrodes substantially adjacent and spaced apart along a length of the sensor, wherein the first and second electrodes are configured to receive user body input via contact electrical shunt electrodes between the user body and the electrodes, and wherein the sensor is configured to receive user body input at different times along the first or at different locations of the sensor, and in response, provide respective corresponding sensor signal values indicative of the location of the user body input.

Aspect 49 may include or be used, or may optionally be combined with the subject matter of aspect 48, to optionally include the first and second elongate electrodes as substantially right triangle, planar electrodes adjacent to each other at or along their hypotenuses.

Aspect 50 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 48 and 49, to optionally include first and second elongate electrodes having different conductivity characteristics.

Aspect 51 may include or be used, or may optionally be combined with the subject matter of one or any combination of aspects 48-50, to optionally include that when the body input is disposed in a first position on the sensor, a surface area of the first electrode contacted by the user body input is greater than the second electrode, and when the body input is disposed in a second position on the sensor, a surface area of the first electrode contacted by the user body input is less than the second electrode.

Each of these non-limiting aspects may exist independently or may be combined in various permutations or combinations with one or more other aspects, examples, or features discussed elsewhere herein.

The above description includes references to the accompanying drawings, which form a part of the detailed description. The drawings illustrate by way of explanation specific embodiments in which the invention may be practiced. These embodiments are also referred to herein as "examples". Such examples may include elements other than those shown or described. However, the inventors also contemplate providing examples of only those elements shown or described. Moreover, the inventors contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), with respect to a particular example (or one or more aspects thereof), or with respect to other examples shown or described herein (or one or more aspects thereof).

In this document, the terms "a" or "an" are used to include one or more, independent of any other instance or usage of "at least one" or "one or more," as is common in patent documents. In this document, the term "or" is used to refer to non-exclusivity, or such that "a or B" includes "a but not B", "B but not a" and "a and B", unless otherwise indicated. In this document, the terms "comprise" and "wherein" are used as plain english equivalents of the respective terms "comprising" and "wherein. Furthermore, in the appended claims, the terms "including" and "comprising" are open-ended, i.e., a system, device, article, composition, preparation, or process that comprises elements other than those listed after such term in the claims, yet are considered to be within the scope of the claims. Furthermore, in the appended claims, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

Geometric terms such as "parallel", "perpendicular", "circular" or "square" are not intended to require absolute mathematical precision unless the context indicates otherwise. Rather, such geometric terms allow for variations due to manufacturing or equivalent functions. For example, if an element is described as "circular" or "substantially circular," the description still includes components that are not exactly circular (e.g., slightly oblong or polygonal elements).

The method examples described herein may be at least partially machine or computer implemented. Some examples may include a computer-readable medium or machine-readable medium encoded with instructions operable to configure an electronic device to perform a method as described in the examples above. Implementations of such methods may include code, such as microcode, component language code, higher-level language code, or the like. Such code may include computer readable instructions for performing various methods. The code may form part of a computer program product. Furthermore, in examples, the code may be tangibly stored on one or more volatile, non-transitory, or non-volatile tangible computer-readable media, such as during execution or at other times. Examples of such tangible computer-readable media may include, but are not limited to, hard disks, removable magnetic disks, removable optical disks (e.g., optical disks and digital video disks), magnetic tape, memory cards or sticks, random Access Memory (RAM), read Only Memory (ROM), and the like.

The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments may be used, for example, by one of ordinary skill in the art upon reading the above description. The abstract is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Furthermore, in the above detailed description, various features may be combined together to simplify the present disclosure. This should not be interpreted as implying that such a non-claimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a single disclosed embodiment. Thus, the appended claims are hereby incorporated into the detailed description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that these embodiments may be combined with one another in various combinations or permutations. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

1. An interface system for an article of active footwear, the interface system comprising:

a touch sensor comprising two or more electrodes spaced apart along an outer surface of an article of footwear and configured to receive user touch input bridging at least two of the electrodes, wherein the sensor is configured to receive the user touch input at a plurality of locations along a length of the sensor; and

a measurement circuit configured to measure capacitance indication signals from the two or more electrodes, wherein the capacitance indication signals include information regarding a location of the user touch input on the sensor;

a processor circuit configured to receive the capacitance indication signal and, in response, control a lacing engine of the article of footwear to alter a tightness characteristic of the article of footwear,

wherein the measurement circuit is configured to measure a rate of change in a capacitance indicating signal of the at least two electrodes, wherein the change in the capacitance indicating signal indicates a gesture or movement along a user touch input of the touch sensor, and the processor circuit is configured to control the lacing engine of the article of footwear based on the measured rate of change in the capacitance indicating signal of the touch sensor.

2. The interface system of claim 1, the processor circuit configured to receive the capacitance indication signal and, in response, provide a corresponding control signal to a lacing engine of the article of active footwear to tighten or loosen the article of active footwear.

3. The interface system of claim 1, the processor circuit configured to receive the capacitance indication signal and, in response, calibrate a foot position sensor of the article of active footwear.

4. The interface system of claim 1, wherein the two or more electrodes of the touch sensor comprise spaced apart substantially planar electrodes.

5. The interface system of claim 4, wherein the substantially planar electrodes are of similar size and have a right triangle shape, and the electrodes are adjacent to each other along all or a portion of their respective hypotenuses.

6. The interface system of claim 1, wherein at least two of the electrodes have different conductive characteristics.

7. The interface system of claim 1, wherein the at least two electrodes comprise flexible conductors disposed on a flexible substrate.

8. The interface system of claim 1, wherein the measurement circuit is configured to measure a change in the capacitance indication signal from the at least two electrodes, wherein the change is indicative of a gesture or movement of the user touch input along or adjacent to the touch sensor.

9. The interface system of claim 8, wherein a change in the capacitance indication signal indicates a swipe gesture along a length of the sensor.

10. The interface system of claim 8, wherein the measurement circuit is configured to measure a rate of change of the capacitance indicating signal, and wherein the rate of change indicates an amplitude of a desired change in footwear tightness.

11. The interface system of claim 1, wherein the location of the user touch input on the sensor corresponds to a magnitude of a desired increase or decrease in a tightness characteristic of the footwear.

12. The interface system of claim 1, wherein the at least two electrodes are fixedly spaced apart, and wherein the user touch input is electrically coupled to the at least two electrodes via a portion of a user's body.

13. A footwear system, comprising:

a lacing engine configured to tighten or loosen the article of footwear in response to the control signal;

a processor circuit configured to generate a control signal;

a housing configured to enclose at least a portion of the lacing engine and the processor circuit; and

a touch sensor comprising two or more electrodes, the sensor being communicatively coupled with the processor circuit and configured to receive a user input, wherein the user input electrically couples the two or more electrodes via a user body;

Wherein the processor circuit is configured to generate the control signal based on the user input,

14. The footwear system of claim 13, wherein the two or more electrodes are elongate substantially planar structures disposed at least partially adjacent to each other and spaced apart from each other.

15. The footwear system of claim 14, wherein the processor circuit is configured to generate the control signal based on a location of the user input to the touch sensor.

16. The footwear system of claim 13, wherein the processor circuit is further configured to initiate a foot sensor calibration procedure in response to the user input.

17. The footwear system of claim 13, wherein the two or more electrodes include substantially planar electrodes having similar sizes and triangular shapes.

18. The footwear system of claim 13, wherein the two or more electrodes have respective different conductive characteristics.

19. The footwear system of claim 13, wherein the touch sensor is disposed at one or more of a tongue, outsole, toe region, or heel region of the article of footwear, and wherein the touch sensor is electrically coupled to the processor circuit.

20. The footwear system of claim 13, wherein the touch sensor is coupled to a sidewall of the housing.

21. The footwear system of claim 13, wherein the two or more electrodes include a flexible electrode disposed on a flexible substrate.

22. The footwear system of claim 13, wherein the touch sensor includes a capacitive sensor configured to measure a capacitance between the two or more electrodes, wherein a magnitude of the capacitance varies according to the user input.

23. The footwear system of claim 13, wherein the touch sensor is configured to receive user input including a swipe gesture that electrically couples the two or more electrodes through a section of the sensor using the user's body.

24. A capacitive user interface for controlling a footwear system, the user interface system comprising:

a touch sensor comprising first and second elongate electrodes substantially adjacent and spaced apart along a first length of the sensor, wherein:

the first and second electrodes are configured to receive a user body input that electrically shunts the electrodes via contact between the user body and the electrodes, and

the sensor is configured to receive the user body input at different locations at different times along a first length of the sensor, and in response, provide respective corresponding sensor signal values indicative of the location of the user body input,

the touch sensor is electrically coupled to a processor circuit configured to receive the sensor signal values and, in response, control a function of the article of footwear,

25. The user interface system of claim 24, wherein the first and second elongate electrodes are substantially right triangle, planar electrodes that are adjacent to each other along their hypotenuses.

26. The user interface system of claim 24, wherein the first and second elongate electrodes have different conductive characteristics.

27. The user interface system of claim 24, wherein at a first location of the user body input on the sensor, a surface area of the first electrode contacted by the user body input is greater than the second electrode, and at a second location of the user body input on the sensor, a surface area of the first electrode contacted by the user body input is less than the second electrode.