CN113840556A

CN113840556A - Touch interface for an active footwear system

Info

Publication number: CN113840556A
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: 2021-12-24
Anticipated expiration: 2040-03-13
Also published as: WO2020186171A1; CN113840556B; EP3937717A1; EP3937717A4; CN118044673A

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 circuitry may be configured to measure a capacitance indicative signal from the two or more electrodes, and the capacitance indicative signal may include information about a location of a user touch input on the sensor.

Description

Touch interface for an active footwear system

Priority requirement

This application claims priority to U.S. patent application serial No. 16/353,739, filed on 3/14/2019, the entire contents of which are incorporated herein by reference.

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. Pat. No.5,929,332 entitled "Sensor shade 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 layer of dielectric material. The foot force sensor may include a conductive interconnect that may have a resistance that varies based on the applied compressive force.

Brown further discusses that when shoes are worn by diabetics or people with various foot ailments, excessive pressure applied to a portion of the foot tends to cause ulcers. The body may include a Force Sensing Resistor (FSR), and a switching circuit coupled to the resistor may activate an alarm unit to alert the wearer to reach or exceed a threshold pressure level.

Devices for automatically tightening an article of footwear have been previously proposed. Liu in U.S. patent No.6,691,433 entitled "Automatic lighting shade" provides a first fastener mounted on an upper portion of a shoe, and a second fastener connected to the closure member and removably engageable with the first fastener to hold the closure 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 wires, and a motor unit. Each wire has a first end connected to the spool and a second end corresponding to the wire hole 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 line 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. Like numerals having different letter suffixes may represent different instances of similar components. The 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 activity footwear according to an example embodiment.

Fig. 2A-2C generally illustrate a sensor system and a motorized harness 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 graph illustrating pressure distribution data for a nominal or average foot (left) and a high arch foot (right) in an article of footwear when the article of footwear is standing.

Fig. 5A and 5B generally illustrate a diagram 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 in accordance with 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 illustrates a flow chart showing an example of using foot presence information from a footwear sensor.

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

FIG. 12 generally illustrates a graph of first time varying information from a capacitive foot presence sensor.

FIG. 13 generally illustrates a graph of second time-varying information from the capacitive foot presence sensor.

FIG. 14 generally shows a graph of third time-varying information from the 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 from a capacitive foot presence sensor and signal morphology limits according to an example embodiment.

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

FIG. 18 generally illustrates an example including a graph illustrating the effect of dielectric fillers on a capacitive indication signal from a capacitive foot presence sensor.

FIG. 19 generally illustrates an example of a graph showing a portion of a third signal indicative of capacitance from a capacitance-based foot presence sensor in footwear.

Fig. 20 generally illustrates an example of foot presence signal information over multiple seating cycles.

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

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

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

FIG. 24 generally illustrates 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 averaged signal.

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

FIG. 27 generally illustrates an example of a graph showing foot presence sensor data.

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

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

Fig. 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 graph showing values of foot presence sensor signals over time and including footwear wear events.

FIG. 33 generally illustrates a graph showing values of the second foot presence sensor signal over time and including a ground effect.

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

Fig. 35 generally illustrates a perspective view of a housing structure having a capacitive interface.

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

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

Fig. 38 generally shows an example of the 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

The concept of self-tightening laces was first defined by a fictitious power lace threaded through the movie "Return to future II", published in 1989 by McFly, Martin

Sports shoes are widely used. Although it is used for

At least one powered lace-up athletic shoe has been released that has an appearance similar to the movie property version of Return to future II, but the internal mechanical systems and surrounding footwear platforms used do not necessarily make it suitable for mass production or everyday use. Furthermore, previous designs of motorized lacing systems have been relatively plagued by problems such as high manufacturing costs, complexity, assembly challenges, lack of applicability, and mechanical weakness or fragility, highlighting only a few of many problems. The present inventors have developed a modular footwear platform to accommodate motorized and non-motorized lacing engines that addresses some or all of the problems discussed above, among others. The components discussed below provide various benefits including, but not limited to, serviceable components, interchangeable automation band engines, robust mechanical designs, robust control algorithms, reliable operation, simplified assembly flow, and retail level customization. Various other advantages of the components described below will be apparent to those skilled in the relevant art.

In an example, a modular automatic-lacing footwear platform includes a midsole secured to an article of footwear for receiving a midsole of a lacing engine. The mid-chassis is designed so that the lacing engine can be added to the footwear platform at the time of purchase. The midsole, as well as other aspects of the modular automated footwear platform, allow different types of lacing engines to be used interchangeably. For example, the motorized lacing engines discussed below may be replaced with manual lacing engines. 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 platform discussed herein may include an outsole actuator interface to provide tightening control and visual feedback to the end user, for example, using LED illumination projected through a translucent protective outsole material. The actuator 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, a footwear platform includes a foot presence sensor to detect when a foot is present in the footwear. When a foot is detected, one or more footwear functions or processes may be initiated, e.g., automatically, without further user input or commands. For example, when the foot is detected as being properly seated in the footwear against the insole, the control circuitry may automatically initiate lace tightening, data collection, footwear diagnostics, or other processes.

Premature activation or activation of the automatic lacing or footwear tightening mechanism can affect the user's experience with the footwear. For example, if the lacing engine is activated before the foot is fully seated against the insole, the user may have difficulty placing the rest of his or her foot into the footwear, or the user may have to manually adjust the lacing tension. The present inventors have thus recognized that the problem to be solved includes determining whether the foot is properly or fully seated in the article of footwear, such as when the toe, midsole, and heel portions are properly aligned with corresponding portions of the insole. The present inventors have further recognized that problems include using as few sensors as possible to accurately determine foot position or foot orientation, for example, reducing sensor cost and assembly cost, and reducing equipment complexity.

Solutions to these problems include providing sensors in the arch and/or heel regions 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 the 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 harness engine housing. In an example, at least a portion of the capacitive sensor is disposed outside of the frenulum 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 various configurations. Capacitive sensors may include plate capacitors in which 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 comprises a plurality of traces, for example arranged substantially in a plane parallel to or coincident with the upper surface of the insole board. 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 the excitation circuit. In an example, the electrodes may have a staggered, vanity configuration. Such capacitive sensors may provide a varying capacitance signal based on the movement of the electrodes themselves relative to each other, and based on the interference of the 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, a 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, moisture, 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 a magnitude of a 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 a foot is present near the sensor, and a second, different value (e.g., corresponding to a high capacitance) when no foot is 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 the step event. Furthermore, there may be a detectable long-term drift in the capacitive signal, which may indicate wear and/or remaining life of shoe components (such as insoles, orthotics, or other components).

In an example, the capacitive sensor includes or is coupled to a capacitive-to-digital converter circuit configured to provide a digital signal indicative of a magnitude of a capacitance sensed by the sensor. In an example, a capacitive sensor includes a processor circuit configured to provide an interrupt signal or logic signal that indicates whether a sensed capacitance value satisfies 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 in capacitance value that may affect sensing.

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 conform to the contours of the foot. In some cases, an air gap (e.g., which may have a relatively low dielectric constant or low relative permittivity) may be present between a portion of the capacitive sensor and the foot while 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 so as to bridge any airspace between the capacitive sensor and the surface of the foot. 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 comfort for the user under the foot.

Various components of the automated footwear platform are discussed below, including the motorized lacing engine, the foot presence sensor, the midsole, and various other components of the platform. While much of the disclosure focuses on foot presence sensing as a trigger for a motorized lacing engine, many aspects of the design discussed are applicable to manual lacing engines, or other circuits or features that may interact with foot presence sensors, for example, to automate other footwear functions, such as data collection or physiological monitoring. The term "automated," as used in "automated footwear platform," is not intended to encompass only systems that operate without specified user input. Rather, the term "automated footwear platform" may include a variety of electric and manual, automatic and manual activation, lacing or retention 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 activity footwear according to an example embodiment. The example of fig. 1 includes a motorized lacing system 100 having a lacing engine 110, a lid 120, an actuator 130, a midsole 140, a midsole 155, and an outsole 165. The lacing engine 110 may include customer replaceable 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, which is 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 near the lacing engine 110 and coupled to internal power or processing circuitry of the lacing engine 110 using one or more electrical conductors.

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

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

The mid-floor 140 includes a lace engine cavity 141, medial and lateral lace guides 142, a front flange 143, a rear flange 144, upper (top) and lower (bottom) surfaces, and an actuator cutout 145. The lace engine cavity 141 is configured to receive the lace engine 110. In this example, the lace engine cavity 141 retains the lace engine 110 in the outboard and fore/aft directions, but does not include features to lock the lace engine 110 in the cavity 141. Optionally, the lacing engine cavity 141 includes detents, tabs, or other mechanical features along one or more of the sidewalls to positively retain the lacing engine 110 within the lacing engine cavity 141.

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

In the example of fig. 1, the midsole plate 140 includes a sculpted or contoured forward flange 143 that extends further on the medial side of the 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 pronounced on the medial side. In this example, the rear flange 144 includes a profile having an extension on both the medial and lateral sides. The illustrated rear flange 144 may provide enhanced outboard stability to the harness engine 110.

In an example, one or more electrodes may be embedded in the mid-sole plate 140 or disposed on the mid-sole plate 140 and may form part of a foot presence sensor, such as part of a capacitive foot presence sensor. In an example, the lacing engine 110 includes sensor circuitry that is electrically coupled to one or more electrodes on the midplane 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 the area adjacent to the midplane 140. In an example, the electrodes extend 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 electrodes extend 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 can monitor or determine the presence of a foot in the footwear, the absence of a foot in the footwear, or foot position characteristics within the footwear. Based on information from one or more such foot presence sensors, footwear including the motorized lacing system 100 can be configured to perform various functions. For example, the foot presence sensor may be configured to provide binary information regarding whether a 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 can be activated, for example, to automatically increase or decrease the tension on the lacing cables, 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 can receive or come from signals of a foot presence sensor.

In an example, the foot presence sensor may be configured to provide information about the location of the foot as it enters the footwear. The motorized lacing system 100 can generally be activated only when the foot is properly positioned or seated in the footwear, for example, to tighten the lacing cables, e.g., against all or a portion of an insole of the article of footwear. A 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 an insole or with respect to some other feature of the article of footwear. The automatic lacing procedure may be interrupted or delayed until information from the sensors 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 "fitting" well to a given foot, e.g., by him determining the relative position of one or more of the arch, heel, toes, or other portions of the foot with respect to corresponding portions 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 part changes over time relative to a specified or previously recorded reference position, for example due to loosening of the lacing cables 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, optical, or other sensor device, which may be configured to sense or receive information about the presence of the body. For example, the electrical sensor may include an impedance sensor configured to measure an impedance characteristic between the at least two electrodes. The electrical sensor may provide a sensor signal having a first value when a body, such as a foot, is positioned near or adjacent to the electrode, and a second, different value when the body is positioned away from the electrode. For example, a first impedance condition may be associated with an empty footwear condition, while a second, lesser 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, for example, radio frequency information. Based on the proximity of the body relative to the antenna, one or more electrical signal characteristics, such as impedance, frequency, or signal amplitude, may be received and analyzed to determine whether a body is present. In an example, a Received Signal Strength Indicator (RSSI) provides information about the power level in a received radio signal. Changes in RSSI, for example with respect to some trace or reference value, can be used to identify the presence or absence of a 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 frequency bands. In an example, frequencies in the kilohertz range may be used, for example about 400 kHz. In an example, power signal variations 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 harness engine 110. The magnet may be remote from the lace engine 110, such as in an auxiliary bottom or insole configured to be worn over the outsole 165. In an example, the magnet is embedded in the foam of the secondary backing or in another compressible material. Changes in the position of the magnet relative to the magnetometer can be sensed and reported via the sensor signal when the user presses the auxiliary bottom while standing or walking.

The second magnetic sensor may comprise a magnetic field sensor configured to sense a change or disruption in magnetic field (e.g., via hall effect). When the body is in proximity to the second magnetic sensor, the sensor may generate a signal indicative of a change in the ambient magnetic field. For example, the second magnetic sensor may comprise a hall effect sensor that varies a voltage output signal in response to changes in the detected magnetic field. The voltage change at the output signal may be due to the creation of a voltage difference 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. patent No.8,752,200 entitled "Devices, systems and methods for security using magnetic field based authentication," teach the use of a unique electromagnetic signature of the human body for authentication. In an example, a magnetic sensor in an article of footwear may be used to authenticate or verify that a current user is the owner of the footwear via a detected electromagnetic signature, and that the article should be automatically laced, e.g., according to one or more designated 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. As the wearer's foot enters the article of footwear, the internal temperature of the article may change when the wearer's own body temperature differs from the environment of the article of footwear. Thus, the temperature sensor may provide an indication of the possible presence or absence of a foot based on temperature changes.

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, such as between opposing 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. When the sensor indicates a change in the sensed light or brightness conditions, an indication of the presence or position of the foot may be provided.

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 with footwear, or other information regarding the foot and/or its relationship to the footwear.

Fig. 2A-2C generally illustrate a sensor system and a motorized harness engine according to some example embodiments. Fig. 2A illustrates various external features of an example lacing engine 110, including a housing structure 150, a cabinet screw 108, a lacing channel 112 (also referred to as a lacing guide relief 112), a lacing channel transition 114, a spool recess 115, a button opening 122, a button 121, a button membrane seal 124, a programming head 128, a spool 131, and a lacing groove 132 in the spool 131. Other designs may similarly be used. For example, other types of switches may be used, such as a sealed dome switch, or the membrane seal 124 may be eliminated, etc. In an example, the harness engine 110 may include one or more interconnects or electrical contacts to interface circuitry internal to the harness engine 110 with circuitry external to the harness 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 housing screw 108. The housing screw 108 may be located near the primary drive mechanism to enhance the structural integrity of the lacing engine 110. The cabinet screws 108 are also used 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, the lacing engine 110 includes a lacing channel 112, the lacing channel 112 receiving a lace or lace cable upon assembly of the engine into an automated footwear platform. The lace channel 112 can include channel walls with chamfered edges to provide a smooth guide surface against or within which the lace cables can travel during operation. A portion of the smooth guiding surface of the lace channel 112 can include a channel transition 114, which can be a widened portion of the lace channel 112 leading into the spool recess 115. Spool recess 115 transitions from channel transition 114 into a generally circular portion that closely follows the contour of spool 131. Spool recess 115 may help retain the lace cable wound on the spool as well as help maintain the position of spool 131. Other aspects of the design may retain other means of the spool 131. In the example of fig. 2A, spool 131 is shaped like half of an yoyo ball, with lacing grooves 132 through the flat top surface of the spool shaft (not shown in fig. 2A) extending downward from opposite sides.

The lateral side of the lacing engine 110 includes a button opening 122 that receives a button 121, and the 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 included in the harness engine 110. In some examples, the housing structure 150 includes a button membrane seal 124 to provide water and dust protection. In this example, the button membrane seal 124 is a clear plastic (or similar material) up to a few mils (thousandths of an inch) thick that can be adhered from the upper surface of the housing structure 150, e.g., 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 the button opening 122. Other types of buttons and sealants may be similarly used.

Fig. 2B is an illustration of a housing structure 150 including a top portion 102 and a bottom portion 104. In this example, the top portion 102 includes features such as a housing screw 108, a lace channel 112, a lace 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 a portion of the top 102 that is released to provide insertion of the button membrane seal 124.

In the example of fig. 2B, the base 104 includes features such as a wireless charger access port 105, a fitting 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 within 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 surface of the structure in one or both of the top portion 102 and the bottom portion 104. In the example of fig. 2B, electrode 170 is shown coupled to base 104. In an example, the electrodes 170 comprise part of a capacitance-based foot presence sensor circuit (e.g., see 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, in another example, the electrode 170 includes one or more portions disposed on an inner surface of the housing structure 150.

Fig. 2C is an illustration of various internal components of the lacing engine 110, according to an example embodiment. In this example, the lacing engine 110 also includes a spool magnet 136, an O-ring seal 138, a worm drive 140, a bushing 141, a worm drive key, a gear box 148, a gear motor 145, a motor encoder 146, a motor circuit board 147, a worm gear 151, a circuit board 160, a motor head 161, a battery connection 162, and a wired charge head 163. Detection of bobbin magnet 136 by a magnetometer (not shown in fig. 2C) helps track the movement of bobbin 131. The O-ring seal 138 serves to seal dust and moisture that may migrate into the lace motor 110 around the spool shaft. The circuit board 160 may include one or more interfaces or interconnects for a foot presence sensor, such as the 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 foot presence 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-driving of the worm drive 140 and gear motor 145, which means that the primary input force imparted from the lace cable via the spool 131 can be resolved over the relatively large worm gear and worm drive teeth. This arrangement protects the 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 tightening the lacing system. The worm drive 140 includes additional features to help protect various vulnerable 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 a pin through a drive shaft out of the gear box 148. This arrangement prevents the worm drive 140 from exerting undue axial forces on the gear box 148 or gear motor 145 by allowing the worm drive 140 to move freely in the axial direction (away from the gear box 148), transferring these axial loads to the bushing 141 and 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 the interface button 301, the capacitive foot presence sensor 310, and the housing structure 150 enclosing a 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. Motion sensor 324 may include a single or multi-axis accelerometer, magnetometer, gyroscope, or other sensor or device configured to sense motion of housing structure 150 (or motion of one or more components within housing structure 150 or coupled to housing structure 150), or the like.

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 a spool 343 to form the drive mechanism 340. In the example of fig. 3, the button 301, the foot presence sensor 310 and the environmental sensor 350 are shown as being external to a portion or portion of the housing structure 150.

In an alternative embodiment, 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 connections 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 sensors 310 and/or from the motion sensors 324 and, in response, control the drive mechanism 340, e.g., to tighten or loosen the footwear around 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, among other functions. In an example, the processor circuit 320 adjusts the operation of the drive mechanism 340 as a function of one or more of detecting the presence of a foot using the foot presence sensor 310, detecting foot orientation or position using the foot presence sensor 310, or detecting a designated gesture using the motion sensor 324.

In an example, the system 300 includes an environmental sensor 350. Information from the environmental sensors 350 may be used to update or adjust a baseline or reference value for 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 environmental conditions 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 a signal 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 winding or unwinding the shaft, 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 charging, 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 graph illustrating pressure distribution data for a nominal or average foot (left) and a high arch foot (right) in article of footwear 400 when the article of footwear is standing. In this example, it can be seen that the areas of relatively greater underfoot pressure include at heel area 401, at ball area 402 (e.g., between the arch and toes), and at big toe area 403 (e.g., the "big toe" area). However, as noted above, it may be advantageous to include various moving parts (e.g., including foot presence sensor 310) in a localized area, such as at or near the arch region. In an example, in the arch region, the housing structure 150 is generally less visible or noticeable to a user when the article of footwear including the housing structure 150 is worn.

In the example of fig. 4, the lacing engine cavity 141 may be disposed in the arch region. One or more electrodes corresponding to the foot presence sensor 310 may be located at or near the 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 with respect to the first location 405. For example, the average foot and the high arch foot will obtain different capacitance values because the surface of the foot itself is at 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 relative to the footwear (e.g., by the user or a technician at a point of sale), for example, to accommodate different foot characteristics of different users and to enhance the quality of the signal 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 located between the foot presence sensor 310 and the foot.

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

In fig. 5A, the 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 functionality that is performed by the processor circuit 320. In the example of fig. 5A, the first electrode assembly 501A and/or the controller circuit 502 can be included in or mounted to an interior portion of the housing structure 150, or can 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 casing structure 150. In an example, the first electrode assembly 501A includes a plurality of traces distributed across an interior, upper surface area of the casing 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 the 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 case structure 150. In an example, the second electrode assembly 501B includes a flexible circuit secured to an inner or outer surface of the housing structure 150 and coupled to the processor circuit 320 via one or more conductors.

In an example, the controller circuit 502 includes 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 proximity of the object or body 550 to the pair of electrodes, and so on, 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 subject or body 550 to be sensed. For example, electrode insulators, the material of the housing structure 150, insole material, insert material 510, socks or other foot covers, body straps, human body kinematics bands, or other materials may be interposed between the body 550 and the electrode assembly 501, for example, to alter the dielectric properties of the footwear, thereby affecting the capacitive detection sensitivity of the sensors containing or using the electrode assembly 501. The controller circuit 502 may be configured to update or adjust an excitation or sensing parameter based on the amount or type of material inserted, for example, to enhance the sensitivity or signal-to-noise ratio of a capacitance value sensed using the electrode assembly 501.

In the example of fig. 5A/B, the first electrode assembly 501A/the 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 assemblies. In an example, an electric field below the electrode assembly may be blocked at least in part using a driven shield located below 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 driven shield may be on the bottom layer of the PCA, or on any of a number of inner layers on the multi-layer PCA. In an example, the driven shield may have a surface area equal to or greater than the first electrode assembly 501A, and may be centered directly below the first electrode assembly 501A.

The driven shield can receive the 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, thereby 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 can help direct and focused detection of a particular region, can help reduce environmental impact, and can help reduce parasitic capacitance effects. In an example, a driven shield is included and can help reduce the effect of temperature changes on the sensor assembly. Temperature can affect the parasitic offset characteristics, for example, temperature variations can cause variations in parasitic ground plane capacitance. 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 sensor measurements.

The driven shield may be similarly configured for use with the second electrode assembly 501B. For example, the second electrode assembly 501B may be disposed above or near the casing 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 driven shield. Additionally or alternatively, when the second electrode assembly 501B is disposed at a location other than at or near the top of the casing structure 15, the driven shield may be disposed elsewhere in the article of footwear.

The preferred location for the shell structure 150 is in the arch region of the footwear as this is an area 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 varied 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 can 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 or

second electrode assemblies

501A or 501B and the body 550.

In an example, an electrode assembly of a capacitive sensor, such as the first electrode assembly 501A or the second electrode assembly 501B, may be configured to sense a difference in signal between a plurality of electrodes, such as between X and Y axis oriented electrodes. In an example, a suitable sampling frequency may be between about 2 and 50 Hz. In some examples, the capacitance-based foot sensing technology may be relatively invariant with respect to sweat (moisture) in the sock on the insole or around the foot. This moisture effect 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 this effect within the moisture levels 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. The

electrodes

601 and 602 may form all or a portion of the first electrode assembly 501A or the second electrode assembly 501B of the example of fig. 5A/B, including, for example, a portion of the 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 the body 550, however, the electrodes may be similarly 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 transmit 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 drive signal to the first electrode 601.

Since the first electrode 601 is excited with 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 or first electrode 601 away from the housing structure 150 (not depicted in the example of fig. 6) and terminate back at the receiver or second electrode 602.

Information about the electric field 615, including information about changes in the electric field 615 due to 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 circuitry 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 can 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 indicative signal to a digital signal. When an object, such as the body 550, invades the electric field 615, including its fringe 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 instead of being received and terminated at the second electrode 602, or passes through the body 550 before being received at the second electrode 602 (e.g., instead of passing through air). 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 electric field information substantially continuously and the information may be sampled continuously or periodically by the ADC 620. The information from the ADC 620 may be processed or updated according to the offset 621 and may then provide a 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 may be based on another capacitor used to track environmental changes over time, temperature, and other variable characteristics of the 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 value. 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., determined using information from the motion sensor 324), the capacitance value may be measured and stored as a reference value, baseline value, or environmental value. When a foot or body approaches the foot presence sensor 310 and the first 601 and second 602 electrodes, the measured capacitance may decrease or increase, for example with respect 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 the body 550 may be determined to be present (absent) in the footwear containing the foot presence sensor 310.

The foot presence sensor 310, as well as the

electrodes

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

In an example, the

electrodes

601 and 602 are arranged in an electrode grid. A capacitive sensor using a grid may include a variable capacitor at the intersection 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 can be applied to the rows or columns and a body or foot near the surface of the sensor can affect the local electric field, which can reduce the mutual capacitance effect. In an example, the change in capacitance at multiple points on the grid can be measured to determine the body position, for example by measuring the voltage in each axis. In an example, the mutual capacitance measurement technique can provide information from multiple locations around the grid simultaneously.

In an example, mutual capacitance measurements use orthogonal grids of transmit and receive electrodes. In such grid-based sensor systems, measurements 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 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 about the X and/or Y detection coordinates may be used to determine when or if the foot is properly or fully seated with respect 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 a self-capacitance sensor, 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, first capacitive sensor 700 includes a plurality of parallel capacitive plates. The plurality of plates may be disposed on or in the housing structure 150, for example, at or near a bottom side 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 plates 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 separate from the housing structure 150. It should be understood that any conductive material may be used, such as a film, ink, deposited metal, or other material. In the example of fig. 7, the plates 701-704 are arranged in a common plane and spaced apart from each other 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 the 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 formed by the six unique combined pairs of capacitor plates 701-704 are 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: a first capacitor plate 701 and a second capacitor plate 702 electrically coupled to provide a first conductor, and a third capacitor plate 703 and a fourth capacitor plate 704 electrically coupled to provide a second conductor.

In the example, the capacitive effect between the first capacitor plate 701 and the second capacitor plate 702 is represented in fig. 7 by the dashed capacitor identified by the letter a. The capacitive effect between the first capacitor plate 701 and the third capacitor plate 703 is represented by the dashed capacitor identified by the letter B. The capacitive effect between the second capacitor plate 702 and the fourth capacitor plate 704 is represented by the dashed capacitor identified by the letter C, and so on. One 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 capacitor plates are represented by the letters used in fig. 7 (e.g., "a", "B", etc.) 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 proximate to the respective pair of capacitor plates may become part of, or may affect, the effective dielectric of a given pair of capacitor plates. That is, a variable dielectric may be provided between each pair of capacitor plates depending on the proximity of the body to the respective 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 medium will be. As the value of the dielectric constant increases, the capacitance value increases. Such a change in capacitance value may be received by processor circuit 320 and used to indicate whether an object is present at or near first capacitive sensor 700.

In the example of the foot presence sensor 310 including the first capacitive sensor 700, a plurality of capacitive sensor drive/monitor circuits may be coupled to the

plate

701 and 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" corresponding 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 in accordance with 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 circuit (e.g., processor circuit 320) may be configured to generate a stimulation or stimulation signal 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 of the body or foot. For example, first electrode 801 and second electrode 802 may be disposed on or near a surface of housing structure 150, such as proximate to the foot when present within footwear that includes housing 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 conductive material, for example with perpendicular lines or traces to form a grid. In this or other capacitive sensors, no direct contact is required between the body or foot and the conductive layer or electrodes. For example, the conductive layers or electrodes 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 or influence the electric field characteristics in the vicinity of the electrodes, and a change in the electric field may be detected.

In an example, individual capacitance values may be measured for the first electrode 801 relative to ground or a reference, and for the second electrode 802 relative to ground or a 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 present 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 an example of a third capacitive sensor 900 according to some examples. Fig. 9C generally shows 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 including a third capacitive sensor 900. Fig. 9C shows a schematic top view of the fourth capacitive sensor 902.

In the example of fig. 9A, the third capacitive sensor 900 includes an electrode area 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 distributed substantially across the surface area of the third capacitive sensor 900. When the third capacitive sensor 900 is installed, the electrode traces may be positioned against an upper or top surface of the housing structure 150. In an example, one or both of the first electrode trace 911 and the second electrode trace 912 can be about 2mm wide. The insulator traces 913 may have about the same width. In examples, the trace width may be selected based on footwear size or insole type, etc. For example, different trace widths may be selected for first electrode trace 911 and second electrode trace 912 and/or for insulator trace 913, e.g., depending on the distance between the traces and the body to be sensed, insole material, gap filler, shell structure 150 material, or other materials used in footwear, e.g., to minimize the signal-to-noise ratio of the capacitance value measured using 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 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. The

input signal conductors

920A and 920B may be configured to couple with one or more input devices, such as dome buttons or other switches, e.g., corresponding to the buttons 121 in the example of fig. 2A.

FIG. 9B shows a sensor assembly 901 including a third capacitive sensor 900,

buttons

121A and 121B, and

membrane seals

124A and 124B. In an example, 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 maintain them in alignment with the conductor surface.

In the example of fig. 9C, the fourth capacitive sensor 902 includes an electrode area 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 include various conductive materials and the fourth capacitive sensor 902 may include 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 a PCA in the housing structure 150.

The present inventors have realised 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 from the foot or body to be detected, for example by an air gap or other intervening material. The present inventors have recognized that solutions may include the use of multiple electrodes of specific shapes, sizes, and orientations to enhance the orientation and relative strength of the electric field generated by the electrodes when energized. That is, the inventors have determined an 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 that extend substantially parallel to each other. For example, the first electrode trace 921 and the second electrode trace 922 may include a plurality of interleaved conductive finger portions, as shown in fig. 9C.

In an example, the second electrode trace 922 may include a coastline or perimeter portion that extends substantially around an outer perimeter edge or surface portion of the fourth capacitive sensor 902 and substantially surrounds 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 and second electrode traces 921, 922 are arranged substantially parallel to each other, an optimal electric field for detecting the presence of a foot is generated, 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 on an upper portion of the first electrode trace 911, which includes vertically extending finger portions, and on a lower portion of the first electrode trace 911, which includes horizontally extending finger portions. 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 times or more thicker than the first electrode trace 921.

In an example, the capacitance values measured by the foot presence sensor 310, for example using one or more of the first, second, third and fourth

capacitive sensors

700, 800, 900 and 902, may be provided to a controller or processor circuit, for example the 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 optionally 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 signals from the foot presence sensor 310 using one or more drive/monitoring circuits, e.g., using the processor circuit 320, (2) determining which, if any, received capacitance signals indicate a capacitance value that meets or exceeds a specified threshold (e.g., 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 the vicinity of the foot presence sensor 310, e.g., based on various specified thresholds being exceeded, and (4) allowing, enabling, adjusting, or inhibiting actuation of the drive mechanism 340 in accordance with the characterization.

Fig. 10 shows a flow chart illustrating an example of a method 1000 that includes using foot presence information from a footwear sensor. At operation 1010, examples include 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 the likelihood that a foot is present in the article of footwear. This information may include electrical signals provided from the foot sensor 310 to the processor circuit 320. In an example, the foot presence information includes quantitative information regarding the position of the foot relative to one or more sensors in the footwear.

At operation 1020, examples include 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 operate 1030 to actuate the drive mechanism 340. For example, when the foot is determined to be fully seated at operation 1020, e.g., based on information from the foot presence sensor 310, the drive mechanism 340 may be engaged via the spool 131 to tighten the footwear lace, 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 re-sample 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 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 foot position information at operation 1040 and receiving 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, examples include monitoring information from one or more buttons associated with the footwear (e.g., button 121). Based on the information from the button 121, the drive mechanism 340 may be instructed to loosen or loosen the lace, such as 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 drive mechanism 340 or for tensioning the lace. For example, lace tension information may be monitored by measuring the drive 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 with the 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 determined automatically by the processor circuit 320, for example, in response to a footwear usage characteristic. 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 exercise (e.g., walking or sitting), the processor circuit may increase the duration of the delay 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 with a return operation 1030, for example, to actuate the drive mechanism 340 to tighten or loosen the footwear around the foot. In an example, the processor circuit 320 includes or incorporates a hysteresis controller for the drive mechanism 340 to help avoid unnecessary lace spools in the event, for example, a minor change in foot position is detected.

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

The states 1110 may include a "transport" state that represents a default or baseline state of an article of active footwear that includes one or more characteristics that may be affected by information from the foot presence sensors 310. In the transport state 1110, various active components of the footwear may be turned off or deactivated to conserve the battery life of the footwear.

In response to the "power on" time 1115, the example may transition to a "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 the 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 motion of the footwear, for example, corresponding to the user placing the footwear in a prepared 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 auto-tie enable event 1123 is encountered or received. The automatic tie activation event 1123 may be triggered manually by a user (e.g., using a 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 auto-tie activation event 1123, a calibration event 1125 occurs. The calibration event 1125 may include setting a reference or baseline value for the capacitance of the foot presence sensor 310, such as to account for environmental effects 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 a specified range or if the environmental impact is too great.

After the auto-tie enable event 1123, the state machine may enter the 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, e.g., indicating the presence of a footer, or indicating a sufficient likelihood of the presence of a footer, the event register may indicate "find footer" 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 a 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, the processor circuit 320 enables the drive mechanism 340 but does not activate the drive mechanism after finding the foot event 1135. At state 1140, the state machine may maintain or suspend additional sensed footwear movement information prior to initiating any initial or further tension adjustments. After waiting for the mobile state 1140, a stomping/walking/standing event 1145 may be detected, and in response, the processor circuit 320 may further adjust the tension characteristics of the footwear.

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 a positive acceleration (e.g., in a specified or general direction) and an "up" or "upright" orientation. In an example, a stomping event includes a "knee-high" or kicking type event in which the user raises 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 lifting event may not trigger a stomping event response, while a fast or fast knee lifting event may trigger a stomping event response.

The walking event may include information from the motion sensor 324 indicating a positive walking mode 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 the motion sensor indicating an up "or" upright "orientation, e.g., without further information from the motion sensor regarding acceleration or directional changes of the footwear. In an example, information regarding a change in a capacitive signal from the capacitive foot presence sensor 310 may be used to discern a standing event, as described further below. That is, the capacitive signal from the 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 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 find foot event 1135.

After stomp/walk/stand event 1145, the state machine may include a "wait to unbundle" state 1150. Waiting to untie lace state 1150 may include monitoring user input and/or gesture information (e.g., using motion sensors 324) to indicate loosening, unthreading, or untieing the lace to the footwear. In the wait to untie lace state 1150, a state manager, such as the processor circuit 320, may indicate that the lace engine or drive mechanism 340 is untied and should return to the wait for foot present signal state 1130. That is, in a first example, an unbundling event 1155 may occur (e.g., in response to a user input), the state machine may transition the footwear to an unbundling state, and the state machine may return to wait for a foot present signal state 1130. In a second example, an automatic lace disabling event 1153 may occur and the footwear may be transitioned 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 recognized relative to a conventional wearing or usage pattern. 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 that incorporates motion sensor 324, the "pause-double click-pause" gesture sequence may itself be a command, but may also be used to wake up the system and indicate that another gesture instruction is to be followed. In an example, a double tap input, e.g., double-tapping the toe of one foot from the heel of the other foot, may be sufficient to indicate a response. For example, a double-tap input may be used to trigger to untie the lace or untie the lace to release 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 influence of the body 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 capacitive signal 1201 may be compared to a particular first threshold capacitance value 1211. The foot presence sensor 310 may be configured to perform the comparison, or the processor circuit 320 may be configured to receive the capacitance information from the foot presence sensor 310 and perform the comparison. In the example of fig. 12, 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 a first interrupt signal INT1 when the first capacitive 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, for example, at the processor circuit 320. In an example, operation 1020 may include using the interrupt signal information to determine whether or possibly a foot is 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 has provided a capacitance value that exceeds the first threshold capacitance value 1211. If the duration exceeds a specified reference duration, the processor circuit 320 may determine that the foot is fully seated or is likely to be fully seated.

In an example, the first interrupt signal INT1 may be used in the example of fig. 11, e.g., 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 vary based on a measured or detected change in the 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. User specification 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 illustrates a graph 1300 of second time-varying information from a capacitive foot presence sensor. The example of fig. 13 illustrates how fluctuations of second capacitance signal 1202 near first threshold capacitance value 1211 may be processed or used to determine more information about the presence or orientation of a foot in footwear.

In an example, the second capacitive signal 1202 is received from the foot presence sensor 310 and the second capacitive 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 environmental characteristics, among others. In the example of fig. 13, the second capacitance signal 1202 may cross 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, such as by indicating a path of travel of the foot as it enters footwear. For example, the time interval bounded by the intersection of the first and second thresholds at times T2 and T3 may indicate the duration of time that the toes or phalanges of the foot are at or near the electrodes of the foot presence sensor 310. When the sensed capacitance is less than the first threshold capacitance value 1211, the separation between T3 and T4 may correspond to the time that the metatarsal joints or metatarsals of the foot are traveling on or near the electrodes of the foot presence sensor 310. As 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 are from the foot presence sensor 310, and thus the resulting measured capacitance between T3 and T4 may be smaller. At time T4, the heel or talus of the foot may slide into position and the arch may sit on the electrodes of the foot presence sensor 310, thereby restoring the sensed capacitance to and exceeding the 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 times T2 and T3 and to present 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 a sequence of interrupt signals. For example, processor circuit 320 may use information about received interrupt signals and about 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 a foot. For example, in fig. 13, the duration between T3 and T4 may be used to provide an indication that a foot is present, 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, for example, as part of a gesture-based user input. In an example, the information regarding whether the 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 accelerometer signal may be ignored by the processor circuit 320 when there is no interrupt signal corresponding to the foot presence sensor.

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

Fig. 14 generally illustrates a graph 1400 of third time-varying information from a capacitive foot presence sensor. The example of fig. 14 shows how reference capacitance changes may be accounted for, for example, due to changes in 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 with a second threshold capacitance 1212 and a time-varying reference capacitance 1213. In the example of fig. 14, the time-varying reference capacitance 1213 increases over time. In other examples, the reference capacitance may decrease over time or may fluctuate, such as during a footwear use event (e.g., over the 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 the insole, outsole, sockliner, orthotic insert, or other components of the footwear.

In an example, a third capacitive signal 1203 is received from the foot presence sensor 310 and the third capacitive signal 1203 is compared to a second threshold capacitance 1212, for example using processing circuitry on the foot presence sensor 310 or using the processor circuit 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, in real time using sensed information from the foot presence sensor 310. The adjustment of the second threshold capacitance 1212 may be based on a time varying reference capacitance 1213.

In an example, the second threshold capacitance 1212 is continuously adjusted, and the amount of adjustment corresponds to the change in the time-varying reference capacitance 1213. 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 time-varying reference capacitance 1213. The stepped adjustment technique is illustrated in fig. 14 by the stepped 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 Δ C 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 compensated by the reference. 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, a 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 foot presence 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 graph 1500 of fourth time varying information from a capacitive foot presence sensor. The example of fig. 15 illustrates how reference capacitance changes may be accounted for, for example, due to changes in various environmental conditions, changes in usage scenarios, or changes due to wear or degradation of footwear components. An example includes a fourth capacitance signal 1204 plotted on graph 1500, having an adaptive threshold capacitance 1214. The fourth capacitive 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 the fourth capacitive signal 1204 for a change in signal amplitude, e.g., a change greater than a specified threshold amplitude amount. That is, when the fourth capacitive signal 1204 includes a magnitude change that meets or exceeds the specified threshold capacitive magnitude Δ C, 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 Δ C relative to the previously specified reference, a 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, the foot presence sensor 310 or the processor circuit 320 may be configured to monitor the fourth capacitance signal 1204 for a subsequent change of at least Δ C, i.e., looking for a capacitance value of C1+ Δ C or C1- Δ C.

In examples that include identifying a capacitance increase for the first time, the interrupt signal state may be changed in response to identifying a capacitance decrease at a subsequent time. However, if a further capacitance increase is identified at a subsequent 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, an increase in capacitance in the fourth capacitance signal 1204 is detected, and the reference may be updated to the second capacitance reference C2. The state of the sixth interrupt signal INT6 may be unchanged as the first and subsequent second capacitance changes indicate an increase. 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 change in capacitance at time T13 is a decrease greater than the specified threshold capacitance amplitude Δ C, the state of the sixth interrupt signal INT6 may change (e.g., from an interrupt asserted state to a deasserted state).

In an example, the change first detected at time T11 and the corresponding interrupt signal INT6 represent the foot sensed by the foot presence sensor 310 and determined to be present in the footwear. The subsequent increase in the reference capacitance represents a change in the baseline capacitance measured by the foot presence sensor 310, for example due to a change in the environment at or near the sensor. The change detected at time T13 may be indicative of a foot removed from the footwear and no longer sensed near foot presence sensor 310. A subsequent change in capacitance (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 limits from a capacitive foot presence sensor, according to an example embodiment. Examples include a fifth capacitive signal 1205 and a sixth capacitive signal 1206 plotted on graph 1600 also includes a morphology constraint 1601. The morphology limit 1601 may be compared to a sampled segment of the capacitance signal from the foot presence sensor 310. The foot presence sensor 310 or the processor circuit 320 may be used to make a comparison to determine whether a particular sample segment meets the morphology constraint 1601. In the example of FIG. 16, the morphology constraint defines a lower limit beyond which the indication capacitance signal segment does not represent, or is likely not to represent, the presence of a foot near the foot presence sensor 310.

The illustrated sampled portion of the fifth capacitive signal 1205 conforms to the morphological constraint 1601. In the example of fig. 16, the morphology constraint 1601 defines a morphology that includes a change in capacitance signal amplitude, or tilt, dwell, and recovery. After recognizing that the fifth capacitive signal 1205 conforms to all or part of the morphological constraint 1601, an interrupt signal may be provided to indicate the presence of a foot or successful detection.

The illustrated sampled portion of the sixth capacitive signal 1206 does not meet the morphological constraint 1601. For example, the sharp drop and long dwell time of the sixth capacitive signal 1206 fall outside the limits defined by the morphology limit 1601, and thus the interrupt signal may be retained, for example, to indicate that the foot is not detected by the foot presence sensor 310.

The morphological constraints 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 morphological constraints 1601 may vary depending on the type of footwear used. That is, the morphological limits 1601 of a basketball shoe may be different than a running shoe, at least in part due to the different geometry or materials of the shoe, or the expected amount of time a user wears or takes off a particular article of footwear. In an example, the morphological limits 1601 may be programmed by a user, for example, to correspond to a user's unique footwear donning and doffing 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 or footwear itself is used. That is, where the foot is not present in the footwear, the sensor may have some associated capacitance value, and this 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, an 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 capacitive characteristics of the 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 degradation of components over time or component replacement, can compromise the accuracy of the 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 change in baseline or reference capacitance, or may be configured to update the baseline or reference capacitance in response to a user input or command. In an example, the 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 capacitive characteristics, the foot presence sensor 310 may maintain its effectiveness over time.

Fig. 17 generally illustrates an example of a representation 1700 of a capacitance-based foot presence sensor in a midsole of an article of footwear and located beneath a dielectric stack. The example 1700 includes a housing structure 150, such as may include or use 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 indicating signal based on the presence or absence of the body 550 in proximity to 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 sock 1751, an air gap (e.g., due to the arch height of body 550 at or near the sensor), sock liner 1750, fasteners 1730 (e.g., velcro), or dielectric filler 1720, among others. 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 the dielectric stack. In an example, the orthotic insert may be part of a dielectric stack.

The present 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 as having hardness or durometer properties, being comfortable to use under the foot in footwear, and providing 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 an example, suitable materials include materials having good weatherability or durability, resistance to low and high temperatures, and resistance to stress cracking.

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

FIG. 18 generally illustrates an example including a graph 1800 illustrating the effect of a dielectric filler 1720 on a capacitance indicating signal from a capacitive foot presence sensor 1701. In the graph 1800, the x-axis represents the number of digital samples and corresponds to elapsed time, and the y-axis represents a relative measure of the capacitance detected by the capacitive foot presence sensor 1701. 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 and 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 include, for example, a polyurethane foam having a first dielectric k-value. Diagram 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 foot presence sensor 1701. For example, a 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 value of zero. The reference or baseline condition may correspond to the absence of a foot in the footwear. That is, a first portion 1820 of the first signal 1801 indicates that a foot is not present in the footwear. At a time corresponding to approximately 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, for example 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 about samples 600 through 1400. At a time corresponding to approximately 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 include various materials other than 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. 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.

Diagram 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 foot presence sensor 1701. A first portion 1820 of the second signal 1802 indicates a reference or baseline capacitance measured by the capacitive foot presence sensor 1701, and in the example of fig. 18, the first portion 1820 of the second signal 1802 indicates the absence of a foot in the footwear. At a time corresponding to approximately 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 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, the amplitudes of the first signal 1801 and the second signal 1802 indicative of capacitance may be different when different dielectric stacks are used. When the dielectric stack includes a high-k dielectric filler 1720, then the difference in amplitude, or difference from the 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 inventors conducted various tests to evaluate the effect of various corrective inserts on capacitive foot sensing techniques. Some of the test results are summarized in fig. 23 and discussed below. Full and partial length corrective insoles were tested. Adding regular (part-length) orthotics to the footwear increases the overall dielectric effect of the stack and reduces the sensitivity to the electric field present at the foot. The sensed signal amplitude (e.g., corresponding to the sensed change in capacitance) is also reduced in the presence of the orthotic. However, the RMS amplitude of the noise floor is similar whether or not orthotics are used. The response under load and unload conditions is similar.

Based on the results of the orthotic test, it is feasible to use capacitive sensing for detecting the presence of a foot for signal-to-noise ratio resolution in the case of regular full-length orthotic. With partial or full length orthotics, SNRs in excess of the desired minimum of about 6db can be used to resolve the presence of a foot, and can be used under light and heavy loading conditions. In an example, the foot presence sensor 310 may include using a capacitive offset range to compensate for the added dielectric effect of the orthotic.

A change in the air gap between the full length orthotic and the electrodes of the 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.

It was found that the different foot regions performed similarly under low load conditions, e.g., under orthotics, the gap distance did not significantly deform. However, under high load conditions, such as when standing on a person, the arch region of the orthotic may be compressed and air gaps may be significantly minimized or eliminated. Thus, under the sensed conditions, 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 creates an air gap between the foot presence sensor 310 and the body to be detected, various materials may be provided or added to compensate for 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 stiffener 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, the amplitude of the signal obtained from the capacitive sensor is generally reduced when using the corrective insert. The RMS amplitudes of the noise characteristics are observed to be approximately similar whether or not the orthosis is used. It was also determined that dielectric members occupying the space between the sensing electrode of the capacitive sensor and the lower surface of the orthotic would have a significant effect on the sensitivity of the capacitive sensor. The signal amplitude of the polyurethane foam (e.g., k value of 1.28) may be reduced by about 70% compared to using a neoprene foam having a dielectric constant or k value of about 5.6. This corresponds to a SNR difference of about 4.6dB with equal noise amplitude. Thus, in the case of carbon fiber orthotics, it is feasible to use capacitive sensing for detecting the presence of a foot for signal to noise ratio. For example, the SNR exceeds the minimum of 6dB required to resolve the presence of a foot.

Fig. 19 generally illustrates an example of a graph 1900 showing a portion of a third signal 1803 indicative of capacitance from a capacitance-based foot presence sensor in footwear. In the graph 1900, the x-axis represents the number of digital samples and corresponds to elapsed time, and the y-axis represents a relative measure of the capacitance detected by the capacitive foot presence sensor 1701. Information from the third signal 1803 may be used to determine whether the user is applying a downward force to the footwear, for example, to identify whether the user is sitting or standing, or to determine the number of steps, or to determine a user's gait characteristics, etc. 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, an 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, corresponding to, for example, a 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 in the x-axis, third signal 1803 includes a footwear wear event, corresponding to body 550 being inserted into footwear, for example. The third signal 1803 includes a footwear take-off event at 1910, or at about sample 10000, after which the third signal 1803 returns to a baseline value.

The example of fig. 19 also includes a specified threshold 1920. The threshold 1920 may correspond to a relative capacitance value indicating that the 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 the threshold 1920, while when the foot or body 550 is not present in the footwear, the relative capacitance may fall below the threshold 1920. Various methods or techniques may be used to dynamically adjust the threshold 1920, such as further described herein, for example to account for environmental changes or footwear material changes.

Between footwear donning and doffing events at 1901 and 1910, the wearer of the article of footwear may transition between a sitting position and a standing position multiple times, corresponding, for example, to the interval between samples 175 and 10250, respectively. 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 pull-on event 1901 includes a turbulent portion of the third signal 1803. That is, third signal 1803 does not show a smooth or gentle transition, but rather fluctuates quickly and irregularly as the user places his or her foot in place within the footwear. In an example, donning event 1901 includes a lace, such as an automatic or manual lace, that 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 of about 220 relative units of capacitance over the first duration 1931.

After the first duration 1931, the user may stand such that the material(s) of the dielectric stack compress and allow the user's foot to access the capacitive sensor 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 units of capacitance over the second duration 1932. That is, the amplitude of the third signal 1803 can change by the first amplitude deformation amount 1951 when the user transitions from sitting to standing, 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, 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 amplitude deformation 1951 may be used to determine the weight of the user or whether the user is running or walking, for example because the user would expect to apply more force to the dielectric stack while running than while walking.

In the example of fig. 19, at about sample 375, when the user returns to a seated 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 about sample 500 in the example of fig. 19) represents the time lapse and the scale change of the x-axis. In an example, samples 0 to 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 when the footwear is older or partially worn, or when a portion of the dielectric stack is compressed without fully retracting or expanding with or without being used.

In the example of fig. 19, a third signal 1803 indicates a number of user transitions between a sitting and standing position. In an example, fourth duration 1934 and sixth duration 1936 correspond to a seated position with minimal force or pressure applied to the dielectric stack in the footwear. The fifth duration 1935 corresponds to a standing position with the elevated force applied to the dielectric stack. In an example, the fourth duration 1934 and the sixth duration 1936 may correspond to an average of about 240 relative units of capacitance. That is, the average of the fourth duration 1934 and the sixth duration 1936 may exceed the average of the first duration 1931 and the 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 type stack or other footwear materials 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 units of capacitance, which exceeds an average of about 120 units of the third duration 1933. Furthermore, the difference between the sitting and standing positions, i.e. the difference between the dielectric stack being stressed or unstressed, may differ for the case of new and old footwear. A first magnitude deformation 1951 indicates a change in relative capacitance between a standing position and a sitting position for a new footwear of about 200 units, and a second magnitude deformation 1952 indicates a change in relative capacitance between a standing position and a sitting position for an old footwear of about 150 units. In the example of fig. 19, the fourth through sixth durations 1934 & 1936 are further indicative of relatively noisy signals as compared to the 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, among other things, a footwear life cycle status or a footwear use characteristic. For example, this information may be used to help prevent injury to the user by reporting or alerting the user that one or more footwear components have worn or been 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 life cycle state of a footwear component, such as an insole component, a orthotic insert, or other component of the footwear.

In an example, information from the capacitive foot sensor may be used to derive or determine step 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, the fluctuations in the third signal 1803 may correspond to different walking events. For example, second duration 1932 may correspond to an interval encompassing a first portion of the user's step, such as when the user's first foot lands 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 third signal 1803. Subsequent to 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 the third signal 1803 may be observed. For example, the amplitude of the third signal 1803 may be increased, such as by the first amplitude distortion 1951. When the user takes a step again and returns to the first foot, the amplitude of the third signal 1803 may be reduced, e.g., the same as or similar to the first amplitude deflection 1951. In an example, the magnitude change may be dependent on, or may be related to, the force exerted by the user on the footwear, which in turn may correspond to the speed at which the user is walking or running. For example, a larger magnitude deformation may correspond to a running pace, while a smaller amount of change may correspond to a walking pace. Thus, one or both of the amount of amplitude variation and the frequency or rate of amplitude variation events may be used to determine the pace of the user.

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

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

In an example, the user's stride 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 location sensor may indicate a total distance the user moved within a specified duration of time. Processor circuit 320, or other processor attached to the footwear, may receive third signal 1803 and correlate the number of signal amplitude change events to the number of steps and distance traveled to determine an average user step 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 about 100 meters per 100 amplitude change events-1 meter per amplitude change event.

In an example, information from the third signal 1803 may be used to determine a user gait characteristic, or a change in user gait. For example, the processor circuit 320 may be configured to monitor the capacitance indicating signal, e.g., the identification signal, for changes over time. For example, processor circuit 320 may monitor a first (or other) duration or first walking event after detecting a donning event. Typically, a user expects to begin walking or running in a similar manner, e.g., using a similar gait, each time the user wears footwear. If processor circuit 320 detects a deviation from a predetermined baseline or average signal characteristic after donning the footwear, the user may be alerted. Similarly, the processor circuit 320 may be configured to detect usage characteristics or deviations that may be associated with user fatigue or mood, which may in turn lead to injury. For example, deviations from a given baseline or reference signal characteristic may indicate that the foot or ankle is rotating or slipping within the footwear, e.g., because a change in foot position may correspondingly change the dielectric properties at or above the capacitance-based foot presence sensor. In examples involving 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 illustrates an example of foot presence signal information over multiple seating cycles. 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 footwear that includes a sensor. A count greater than zero indicates that the capacitive foot presence sensor senses something other than a no-foot condition, such as a foot or other body or object present in the sensor and thus in or near 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 the force applied by the foot to the sole of the footwear, such as described in the example of fig. 19 above. For example, when a foot is present in the footwear and the wearer is seated, and therefore does not exert a significant force on the sole of the footwear, then the sensor may record a first, lesser number of counts. When a foot is present in the footwear and the wearer is standing, thus applying a relatively greater force to the sole of the footwear, then the sensor may record a second, greater number of counts. These and other count amplitude variation conditions are generally illustrated 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 footeless condition interval is indicated at a first interval 2001 from time zero to about time 900. During the footeless condition of the first interval 2001, the sensor records about zero counts. After the no foot condition first interval 2001, the first dressing interval 2002 is indicated from about time 900 to about time 1250. During 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 footwear, including, for example, flattening out any wrinkles in the insert supporting the foot.

After first wear interval 2002, first sitting interval 2003 is indicated as being 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 seating interval 2003, the wearer is substantially stationary and remains in a relaxed position. 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 raising interval 2004 is indicated from about time 1750 to time 2200. In the first lifting 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 sensors. Since the wearer's foot is still physically present in the footwear during the first raising interval 2004, the count magnitude 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 approximately 100 counts during the first foot-lifting interval 2004.

After first foot raising interval 2004, first standing interval 2005 is indicated from about time 2200 to time 2750. During the first standing interval 2005, the wearer places his or her foot on the ground and stands upright, 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 magnitude may be greater than that observed during first sitting interval 2003 and first lifting interval 2004 because during 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 first stance interval 2005, first step row/walk interval 2006 is indicated from about time 2750 to time 3200. During first step/walking interval 2006, the wearer walks or walks while wearing the footwear. The count amplitude fluctuates during the first step row/walking interval 2006 and the fluctuations correspond to the wearer's step cycle. For example, the peak or maximum value of the count amplitude during the first step row/walking interval 2006 corresponds to an instance when the wearer applies a force to footwear that includes a sensor, such as when the wearer's foot contacts the ground. The count amplitude trough or minimum during the first walking/walking interval 2006 corresponds to an example where the wearer lifts 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-raising interval 2004. In an example, the count flat area corresponds to a duration of time that the foot is on the ground (e.g., corresponding to a walking event) or a duration of time that the foot is lifted off the ground. Thus, the rate of travel of the user may be discerned or determined based on the relative length of each flat region.

After first step row/walk interval 2006, second sit 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 less than the count amplitude observed during the first sitting interval 2003. This variation can be attributed to, among other factors: a change in a baseline or reference capacitance of the sensor, an environmental effect, or a pose of the wearer after the first walking/walking interval 2006.

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

After returning to zero count at about time 3750, the example of fig. 20 includes a second cycle beginning at about time 4500, which includes another wear interval, a sit-down interval, a raise-foot interval, a stand interval, a walk/walk interval, a second sit-down interval, and a take-off 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 present threshold may be selected to be about 30 signal counts from the sensor. When more than a specified number of counts are observed, the foot presence threshold may indicate that a foot is present in the footwear (or that there is a high likelihood that a foot is present in the footwear). Similarly, when less than a specified number of counts is 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 electrodes are damaged or changed, the baseline capacitance value of the sensor may change, and correspondingly the reference measurement of the sensor may change. In an example, various electric and/or magnetic fields may affect the behavior of the sensor, which may result in a change in a baseline capacitance value of the sensor. In an example, the user may adjust the foot presence sensing sensitivity of the sensor, e.g., make the sensor (and its triggered function) more or less responsive to a foot detection event. The foot presence threshold may be adjusted to accommodate any one or more of these or other changes without losing its foot presence sensing functionality.

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 casing or housing configured to house the electrode assembly, although other shapes may similarly be 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, for example, may be arranged side-by-side or concentrically.

Fig. 21A includes a first electrode assembly 2101 including 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 the illustrated example, the average first thickness T1 is about 2 millimeters and includes an approximately 2mm wide conductive band or loop 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 comprising a central second non-conductive region 2132 having a second surface area a2 less than a 1. 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 an approximately 4mm wide conductive band or loop 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 area 2133 having a third surface area A3 less than a 2. The third electrode assembly 2103 includes a third electrode region 2123 having an average third thickness T3 greater than T2. In an example, the average third thickness T3 is about 6 millimeters and includes an approximately 6mm wide conductive band or loop 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 that includes a central flood electrode region 2124 having a surface area greater than any of the first through third electrode regions 2121-2123 of FIGS. 21A-21C. In an example, the assembly includes a fourth non-conductive boundary 2114 outside of the central flood electrode region 2124. That is, the fourth electrode assembly 2104 includes electrodes that occupy substantially all of the available surface area, but does not include a central non-conductive region.

The foot presence sensor 310 is generally discussed herein as including the use of an electrode assembly, e.g., including one or more electrodes disposed under the foot. However, multiple 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 the foot presence sensor 310 may be disposed in the arch region and a second electrode assembly of the foot presence sensor 310 may be disposed in the toe region of the footwear. The different electrode assemblies may be commonly controlled and share information by the processor circuit 320. Information from multiple different electrode assemblies may be used together to determine the position or state of the foot within the footwear. For example, using at least two different electrode assemblies spaced 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 foot position within the footwear. For example, a signal from a first component may transition state before a signal from a second component when the foot enters or leaves the footwear. Information regarding the duration between state changes may be used to determine whether a 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 assess 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 a 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 the first electrode assembly 2101 (e.g., having a first electrode region 2121 that is 2mm wide), a second curve 2202 corresponds to the second electrode assembly 2102 (e.g., having a second electrode region 2122 that is 4mm wide), a third curve 2203 corresponds to the third electrode assembly 2103 (e.g., having a third electrode region 2123 that is 6mm wide), and a fourth curve 2204 corresponds to the fourth electrode assembly 2104 (e.g., having a flood electrode region 2124).

In the example of fig. 22, the first-fourth curves 2201-2204 indicate the relationship between foot impact force on a 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 that includes 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. At the indicated intervals from 20 to 80 pounds of force, the sensor comprising the second electrode assembly 2102 indicated a difference of about 110 counts.

In the example of fig. 22, the 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, the fourth curve 2204 indicates that when a weight of about 20 pounds is applied to the 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 including 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 intervals shown. However, the different slopes of the first-fourth curves 2201-2204 indicate different sensor sensitivities to weight changes. For example, the first curve 2201 indicates that the first electrode assembly 2101 is relatively insensitive to weight changes, showing a 50 count difference at a 60 pound-force swing. In contrast, the fourth curve 2204 indicates that the fourth electrode assembly 2104 has a relatively large sensitivity to weight changes and shows a difference in 175 counts at the same swing of 60 lbf. Thus, in some examples, a sensor incorporating or using the fourth electrode assembly 2104 can provide greater resolution and more information regarding 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 orthotic inserts. As explained above, the orthotic insert may comprise a portion of a dielectric stack in footwear. The inventors conducted various tests using the planar electrode configurations discussed above to evaluate the effect of various corrective inserts on capacitive foot sensing techniques. In the example of fig. 23, a third electrode assembly 2103 (e.g., having a 6mm wide conductor) was used during testing. Full and partial length corrective insoles were tested. Adding regular (part-length) orthotics to the footwear increases the overall dielectric effect of the stack and reduces the sensitivity to the electric field present at the foot. The sensed signal amplitude (e.g., corresponding to the sensed change in capacitance) is also reduced in the presence of the orthotic. However, the RMS amplitude of the noise floor is similar whether or not orthotics are used. The response under load and unload conditions is similar. In the example of FIG. 23, a baseline or reference capacitance or offset is established for each tested interposer to zero out the test system.

In the example of fig. 23, the first orthotic curve 2301 corresponds to a fiberglass insert, the second orthotic curve 2302 corresponds to a rigid polymer insert, the third orthotic curve 2303 corresponds to a polyurethane insert (e.g., a "standard" or factory provided insole material), and the fourth orthotic curve 2304 corresponds to a carbon fiber insert. Each of the first through fourth orthotic curves 2301-2304 indicates that a substantially linear relationship between force and sensor output or count (see, e.g., FIG. 22) remains substantially constant 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) for a given insert decreases with increasing stiffness as long as the insert is not electrically 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 the steepest in the test. This increase in capacitance 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 showing a relationship between a capacitive sensor response and a change in fluid saturation of one or more components of footwear including a capacitive sensor. The example of graph 2400 shows the effect of simulated perspiration applied to the ankle of a foot wearing a sock and placed within an article of footwear including a capacitive sensor. Examples correspond to tests conducted in which the capacitive sensors are monitored over time and over multiple sit/stand cycles as sweat agents are added to the test assembly.

The testing component includes a foot equipped with a sock and footwear that includes a foot presence sensor in accordance with one or more embodiments discussed herein. Sweat is simulated by introducing saline solution into the ankle area of the foot. Approximately 10 ml 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 amount 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 counts. During 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 a third interval 2403, the wearer stands up, further increasing the count output from the sensor (e.g., to about 200 counts). After the third interval 2403, a number of sit/stand cycles are continued, with simulated sweat or saline added at 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 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 was substantially saturated after about 60 ml of simulated sweat was added. Thus, a relative slope of the baseline or reference count value may be observed when between about zero and 60 milliliters of fluid is added, however, the baseline or reference count is relatively constant when more than 60 milliliters of liquid is added.

Although baseline or reference conditions vary for sitting configurations passing through different levels of fluid saturation, the difference in counts 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 can be observed from fig. 24, the difference in the first count between the second interval 2402 and the third interval 2403, or in a dry condition, is about 60 counts. The difference in counts between sitting and standing intervals under saturated conditions, such as at the 70mL indication on graph 2400, was observed to be about 75 counts, or only about 15 counts different from that observed under dry or unsaturated conditions. Thus, in the presence of a changing baseline or reference capacitance condition, information regarding footwear usage, including information regarding the presence or absence of a foot, or information regarding 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 positions.

FIG. 25 generally illustrates an example of the graph of FIG. 24 showing the relationship between sensor response and simulated sweat for an average signal. In the example of fig. 25, an average curve 2410, calculated as a slow moving average of sensor counts, is imposed on 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, a subsequent comparison of sensor outputs may be made using the absolute reference indicated by the average curve 2410, e.g., rather than relying on or using relative sensor information, such as previous footwear occupancy from the same or a different wearer. That is, information regarding a 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, used to determine whether footwear is present in the footwear, and so forth.

Fig. 26 generally illustrates an example of a foot presence sensor state diagram 2600 that may optionally include or use a sweat compensation method. The foot presence sensor state diagram 2600 includes a first block 2610 of states and a second block 2620 of states. The first block 2610 represents the basic foot presence detection functionality of the system. Second block 2620 includes a compensation function that may optionally be used to add 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 interacts with or uses information from the foot presence sensor 310 and the 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 a condition that may generate an interrupt signal, 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, the FOOT presence sensor 310 may provide an interrupt, which may be received as an event FOOT _ increase _ EGRESS in the footwear system state diagram 3100 of fig. 31, as discussed below.

The foot presence sensor state diagram 2600 generally illustrates an example that includes monitoring signal information from the 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 may apply 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 a user of the footwear sweat or moisture content, a change due to footwear material compression or decompression, 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 near 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 circuitry to determine whether the non-zero response indicates the presence of a foot or noise. For example, when the footwear is donned and the capacitive sensor records a non-reference or baseline capacitance, a specified capacitance threshold may be met or exceeded, thereby waking up further processing to verify whether the foot is present in the footwear.

At state 2602, examples include populating a memory buffer with sensor data. The data collected is sufficient to determine the presence or absence of a foot, or to distinguish 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 "debounce" analysis to determine whether a foot is present. The dejitter analysis may include signal smoothing, averaging, time delay or other processing, etc., to help distinguish signal noise from available foot presence information.

Debounce analysis may include monitoring the capacitance indicating signal change and discerning a speed characteristic from the capacitance indicating signal. In an example, debounce analysis includes monitoring speed characteristics to determine when a 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 deemed to be sufficiently seated so that the system may trigger one or more other functions of the automated footwear, such as an automatic lacing function or a data collection function.

In the example of fig. 26, the debounce analysis includes "capacitance sense value is above threshold and slope is below threshold". A "capacitance sensing value above a threshold value" indicates that the capacitance indicating signal from the capacitive foot presence sensor records a value that exceeds a reference or baseline capacitance value. "slope below a 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, thereby triggering one or more other functions of the footwear. In an example, the interrupt includes the FOOT _ increase _ entries 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 a 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. In 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 based on the foot presence determination may be sent to one or more processors, circuits, or devices, for example, to initiate another activity or process when the foot presence is determined. For example, the interrupt may be used by a lacing engine to initiate an automatic lacing program or hardware process, such as in accordance with the footwear system state diagram 3100 of fig. 31. At state 2604, the system remains in a state that includes a positive foot present indication, and the system may be configured to wait for another signal or interrupt to initiate or proceed with a subsequent process.

From state 2604, the system may enter a relatively low power or sleep state 2605, where the system may retain further data or detected changes in sensor signals. In an example, state 2605 represents a state in which a foot is present in the shoe and the shoe is actively using or worn. For example, if the footwear is automatically strapped and secured to the foot based on the foot presence determination from debounce analysis at state 2603, the footwear may remain in a secured state around the foot while periodically monitoring the sensor state or waiting for another interrupt to change the state of the footwear at state 2605. In an example, monitoring the capacitance indication signal from the foot presence sensor at state 2605 includes monitoring the signal at a relatively low frequency, e.g., 1-2Hz or less, to identify whether the capacitance indication 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 continues to state 2606, where the footer presence indication interrupt may be cleared. In an example, continuing to state 2606 may include a hardware or software check to determine whether the baseline or reference characteristics of the sensor should be updated. For example, the symbol "HW Anti-touch reverse Threshold Passed" indicates an automatic recalibration procedure. If a foot is removed and in state 2606, the foot present signal indicating 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 activities, such as from state 2601. In an example, at state 2606, each time a foot is removed from the footwear, calibration or recalibration may be initiated.

Variations in the footwear itself, such as during use of the footwear, may result in sensor signals indicating the presence of a foot, when in fact a foot is not present in the footwear. For example, fluid saturation or moisture content 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 false indications that a foot is present in the footwear. Thus, at state 2605, the system may be configured to periodically wake up or perform analysis and replenishment routines to verify whether a foot is present in the footwear.

In the example of fig. 26, the compensation routine may include timed 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 the signal for changes. If the signal includes a change that meets or exceeds a specified threshold change or variance, 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 a foot may not be present in the footwear and the system may return to state 2601. In this example, returning to state 2601 includes recalibrating to determine whether the baseline or reference capacitance indication signal needs to be updated.

In an example, foot displacement information (e.g., relative to sensors internal to the footwear) may be determined using count information from a capacitive sensor in the footwear (e.g., foot presence sensor 310). The slope of the displacement information may represent a velocity characteristic of the foot inside the footwear, and in some examples, may represent the velocity of the footwear itself. In an example, information regarding the speed characteristics of the foot may be used to trigger one or more features of the footwear. For example, the speed profile may be used to identify a footwear donning and doffing event, which may trigger an automatic lacing or untieing 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 materials (e.g., compression and decompression), etc. For example, a user initiated or commanded calibration may be used to re-calibrate 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 a lacing engine 110. In the example of fig. 26, the foot presence sensor 310 may be a system input configured to receive a user command, such as foot presence or foot absence. In response to a user command, i.e., foot present or foot not present, 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 the characteristic or value of the command signal and the reference value. For example, 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 a digital count, which represents the capacitance, as discussed elsewhere herein.

In an example, fig. 26 may include or use a state including receiving a calibration indication, such as [ calibration capture ] 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 the value of the current indicated capacitance from the foot presence sensor 310 and update or change the reference value based on the measured current value. The state machine may then use the changed reference value to determine the presence or absence of a foot, such as transitioning from state 2601 to 2602.

FIG. 27 generally illustrates 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 the 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 not being present in 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 over 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., attack time or sensitivity, or immunity to noise or rapid signal changes or signal bounce).

In an example, the magnitude of the third curve 2703 may be indicative of a relative speed of the footwear including the sensor, or of a foot inside the footwear when the foot is wearing the footwear. The large magnitude 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 magnitude of the third curve 2703 may correspond to a small velocity.

The example of fig. 27 also includes a fourth curve 2704 (shown as an alternating short/long dashed line). A fourth curve 2704 indicates whether a 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 velocity, the presence of a foot may be indicated. In an example, the detected speed change may be a speed change that is greater than a specified threshold speed amount. In another example, the detected speed change may include a speed profile comparison, such as comparing a speed change or waveform shape to a known speed change or shape corresponding to the presence of the 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 velocity or displacement information may optionally be used with information regarding the velocity of the foot relative to sensors inside the footwear. For example, 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 velocity information may be used to optimize the tension characteristics to a specified tightness, e.g., just tight enough to prevent relative motion (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 foot or footwear velocity or acceleration is not detected, the tension characteristic may be determined to be excessive or unnecessary and footwear tension may be relaxed. For example, if the foot swells during activity, the footwear may be relaxed (e.g., the lace may be loosened) until some specified small velocity is detected.

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

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

Fig. 28A-30D generally illustrate examples of a footbed assembly having a lace engine assembly 2803, and various techniques or examples for installing or retaining the lace engine assembly 2803 in a lace engine cavity 2801 in a footbed. 28A, 29B, 29C, 30B, 30C, and 30D generally illustrate an example of a user accessing the lacing engine assembly 2803 and/or the lacing engine cavity 2801 from a user perspective. The user's hand depicted in the figures is not required, 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 having a rear seat cover 2802. The footbed assembly may include a lace engine chamber 2801, and a lace engine assembly 2803 may be installed in the lace engine chamber 2801. In the example of fig. 28A, the seat back cover 2802 is shown in a raised position to provide a view of the harness engine chamber 2801 in which the harness engine assembly is disposed. In fig. 28B, the seat back cover 2802 is installed such that it covers substantially all of the harness engine chamber 2801.

In an example, the lacing engine assembly 2803 can include electrodes of a capacitive sensor (see, e.g., the examples of the electrode assembly in fig. 21A-21D, as well as 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) may be disposed over the harness engine assembly, and the seat back cover 2802 may be disposed over the dielectric member. In an example, the rear seat cover 2802 may be contoured to the contour of the arch of the wearer's foot. In an example, the seat back cover 2802 is bowed or umbrella shaped to help transfer moisture away from the lace engine assembly 2803. The back seat cover 2802 may comprise various rigid or flexible materials, including, for example, carbon fiber, EVA, or neoprene, and may be configured to be relatively conductive, thereby enhancing the body sensing sensitivity of the underlying capacitive sensor. Accordingly, the seat back cover 2802 may provide a protective covering for the lace engine assembly 2803 and may, in some examples, enhance foot sensing capabilities.

Fig. 29A-29D generally illustrate an example of a footbed assembly having a first shackle cover for lacing the 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 hook and loop cover provides a hanging mechanism that can be used to reduce or decompress the pressure on a dielectric stack disposed above the lacing engine assembly 2803. That is, the lid may be biased toward an uncompressed state with the dielectric stack.

In the example of fig. 29A, the first hook and loop cover includes a hook perimeter portion 2901 that follows the perimeter of the lace 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 lace engine cavity 2801, and the inside edge of the hook perimeter portion 2901 may be flexible and may be manually raised to accommodate insertion of the lace engine assembly 2803 into the cavity. The harness engine assembly 2803 may be covered with a loop material cover 2902. The loop material cover 2902 may help retain the lace engine assembly 2803 inside the lace engine cavity 2801 in the footwear. In some examples, the loop material cover 2902 includes an outwardly facing side that is hydrophobic and is configured to help divert moisture away from the harness engine.

Fig. 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 the 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. A side edge of the hook material cover 3001 may be coupled to the footbed at a first side of the lacing engine cavity 2801, and may be flexible and may be manually raised to accommodate insertion of the lacing engine assembly 2803 into the lacing engine cavity 2801 (e.g., see 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 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 adjacent to or on a portion of the lacing engine assembly 2803. In the example of fig. 30D, the dielectric stack 3004 comprises 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 can 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 help transfer moisture away from the lacing engine assembly 2803.

In the example of fig. 30D, the dielectric stack 3004 overlaps 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 shell, 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 influence on the foot presence indicating signal from the capacitive foot presence sensor in the lacing engine assembly 2803 or coupled to the lacing engine assembly 2803.

The hook and loop assemblies 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 field used by the capacitive sensors inside (or near) the lacing engine assembly 2803 to monitor or detect whether a 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 effect of repeatedly compressing the dielectric stack 3004 due to footwear use, thereby preserving foot presence sensing signal sensitivity, fidelity, and dynamic range during repeated or extended 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: 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 shows how components 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 indicate different states including a state armed (state [0]), a state waiting to stand (state [1]), a state unbelted (state [2]), and a state in motion (state [3 ]).

In the example of FIG. 31, each transition between states is annotated with PRECONDITION/EVENT/[ ACTION ]. Preconduction indicates a requirement or prerequisite for a change from a particular state. For example, preconduction changing from state [0] to state [1] may include the system motor having a minimum threshold charge (BATT _ OK) and (& &) the lacing engine 110 being in a HOME or un-spooled position (AT-HOME) such that the footwear lace is relaxed and not tightened. A minimum threshold charge limit may be imposed to ensure that the system has sufficient remaining battery life to unwind the bobbin after the bobbin is actuated.

Referring again to the example of changing from state [0] to state [1], the EVENT may include a FOOT entering or exiting footwear (FOOT _ increase _ shoes), such as may be detected using the FOOT presence sensor 310. In an example, the FOOT _ increase _ events can 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, for example, an accelerometer). In an example, information from motion sensor 324 may be used to confirm the orientation of the footwear and/or the presence of the foot prior to initiating a lacing action.

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

In the example of fig. 31, an EVENT including lace may be a condition or condition where 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 original location. An EVENT including autoice 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 footwear tightness or tension in the lace.

In the example of fig. 31, [ ACTION ] including [ CS _ RESTART ] may include a command that may trigger or initiate a calibration event for the foot presence sensor 310. For example, [ CS _ RESTART ] may be declared 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 taken off. In examples, the footwear may be configured to recalibrate the reference condition of the foot presence sensor 310 when the footwear is removed after unbundling or unthreading, or the footwear may be configured to recalibrate the reference condition of the foot presence sensor 310 when the footwear is removed with brute force (e.g., by pulling the footwear away from the foot while the lace is still tensioned or wound).

In the example of FIG. 31, [ ACTION ] comprising DISABLE _ SENSOR may include disabling the 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 maintain the foot inside the footwear, such as in state [3], the processor circuit 320 may be disabled 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 from the foot presence sensor 310 that a foot is present in the footwear, the system may stop listening for commands or interrupts from the foot presence sensor 310. In an example, another user command than the presence of the foot may be used to un-spool or release the lace and remove the footwear, for example using an ARM command. The ARM command may be declared in various ways, such as from a detected footwear gesture, pressing a button, or through 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 recognize or sense a change in the electric field. In an example, the foot presence sensor 310 recognizes 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., the examples and discussion of fig. 5A, 5B, and 6). However, the sensor signal paths 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 pass substantially through the padding material or insole, such as insert material 510, towards the foot or body to be detected, and may then return 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 that, unless mitigated, may result in erroneous readings by the foot presence sensor 310. For example, the field path may extend from the electrode(s) of the foot presence sensor 310 through the outsole and then back to the PCA. In examples where the 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, extend to the ground, and then return to the PCA in an upward direction. In other words, the additional field path may exist in a direction opposite to the target sensing direction of the sensor. In examples where the electrodes and PCA are placed under the foot, such parasitic fields outside the footwear may interact with the environment, such as the floor, or the hands when the footwear is grasped around the bottom or arch region of the footwear. Depending on the footwear material, the parasitic field may affect the capacitance measured by the foot presence sensor 310. In an example, the parasitic field may cause a change in the sensor capacitance that is greater than the lowest signal capacitance that results from some affirmative signal (e.g., a foot in footwear). Further, parasitic fields can lead to false foot presence detection events and can lead to abnormal or unpredictable lacing engine triggers or behaviors.

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 an example, 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 focus the sensor field in a particular direction or area. In an example, other adjustments to the field or field focus may be made by adjusting the shape or material properties of the dielectric stack (e.g., dielectric stack 3004) used with the foot presence sensor 310.

In an example, adverse ground effects may be identified by analyzing the output signals from the foot presence sensors 310, and such adverse ground effects may be mitigated with a 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 capacitive indicative signals from the foot presence sensor 310, using information from the motion sensor 324, or using other techniques.

In an example, information from the signal of the foot presence sensor 310 may be used to separate the donning event from adverse ground effects or parasitic field regions. 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 showing values of the first foot presence sensor signal 3201 over time and including a footwear wear event. The example of fig. 32 includes a first foot present 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, and a low state indicates that the foot is not present. In an example, the value of the first foot present 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 wearing the footwear. Foot insertion and detection of the foot presence sensor 310 occurs at approximately sample 1300, as represented by a significant rise in the 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 the output of the 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 bottom of the footwear. By approximately 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 FOOT _ increase _ events 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 showing the values of the second foot presence sensor signal 3301 over time. The example of fig. 33 includes a ground effect without footwear donning. 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, and a low state indicates that the foot is not present.

In the example of fig. 33, the surface 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 _ increase _ events from the example of fig. 31.

From the example of fig. 32, the time for which the shoe 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 where 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 example of fig. 32 and 33, the peak value and the 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 present 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 amplitude of 80 counts and a substantially similar steady state amplitude 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 the transition takes about 170 samples or three seconds, from initial wear to fully seated and stable, and the corresponding sensor signal may have a magnitude of about 140 and 160 counts. In an example including a surface event, on the other hand, the signal rises by about 81 samples, less than two seconds, from start to interrupt generation, and the corresponding sensor signal has an amplitude of 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 graph 3400 representing 51 wear events from 25 different individuals. In an example, the timing begins with a previous transition of the foot presence sensor signal above the sensing threshold and terminates with the generation of an interrupt (e.g., in a sensor signal steady state). In an example, the amplitudes are averaged over a data window comprising 12 samples before issuing the interrupt. The 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 non-ground effect samples are shown as solid dots. Ground effect samples represent a relatively short duration and low amplitude compared to other samples. In an example, to determine the unique extent of the ground effect samples, a normal distribution may be assumed, and mean and standard deviation values may be calculated. In the example of fig. 34, the vertical axis is set at a time corresponding to the mean minus one standard deviation, or at 100 samples (2 seconds). The horizontal axis is at a magnitude corresponding to the average magnitude 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 samples are the only samples 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 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 the motion sensors 324 may be received and analyzed to determine footwear orientation. Further, in state [1], the system may analyze the capacitance indicative 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, footwear system state machine 3100 may return to state 0, for example, by issuing a CS _ RESTART. The S _ RESTART command may remove (tare out) the parasitic field and may abort the tie command.

In an example, the calculation of the wear time and average amplitude may be performed during state [1], and the calculated values may be stored in a register or buffer circuit of the sensor controller. When production is interrupted, 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 the 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 results (e.g., true or false) may be combined (e.g., via a 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, the one or more interface buttons 301 from the example of fig. 3 may be provided using a capacitance-based input device or a touch sensor. The touch sensor can be disposed on the housing structure 150 or attached to the housing structure 150 and coupled to circuitry therein, or the touch sensor can be remote from the housing structure 150 and coupled to circuitry inside the housing structure 150 using electrical conduction. For example, the touch sensor may be disposed on the footwear tongue, outsole, toe area, heel area, or elsewhere. In an example, a capacitive touch sensor can be disposed on or in the housing structure 150, and an interface is 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, which may include, for example, 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 the housing structure 150 including the capacitive interface 3500. The 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 an example, one or more electrodes may comprise a flexible conductive material, such as a film, a conductive polymer, or a fiber, or other material. The electrodes may comprise a material deposited on or integrated with a flexible or rigid substrate material, such as a fabric or polymer substrate.

In an example, the first electrode 3501 and the second electrode 3502 may 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 along one of their diagonals into two right angle triangular structures that are then spaced apart along their respective hypotenuse or oblique sides. In an example, different shaped conductive structures may be eaten 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, e.g., in terms of length or area. In an example, the electrodes may be offset from each other in a lateral direction such that one electrode extends away from a side edge of the other electrode. In this example, a 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 in a structure of which shapes are mirror images of each other. The examples of fig. 35-39 generally show a touch sensor having two electrodes, however, additional electrodes may similarly be used, e.g., 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 so that a fingertip can 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 may have different conductive properties. For example, the first electrode 3501 may include or may be made of a first material having a first electrically conductive characteristic, and the second electrode 3502 may include or may be made of a second material having a second, different, electrically conductive characteristic.

The first electrode 3501 and the second electrode 3502 can be coupled to a drive circuit inside the housing structure 150 or elsewhere. The drive circuitry, which may include, for example, processor circuitry, a signal generator, or other circuitry, may periodically or intermittently poll or measure the capacitance from the electrodes to identify a change in capacitance, such as may indicate a user input or instruction to the processor circuitry 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 measure the response from the same electrodes. Based on the response, capacitance or a capacitance indicating signal may be measured.

The capacitance measured from the electrodes may be affected or changed by the user's body at, near or beside the electrodes, and may further be affected or changed 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 is not touching the electrode, or when the user is touching 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 mapping may, for example, include a user input or "swipe" area that may be used to adjust the lace state of the lace spool characteristics, e.g., in response to a user dragging a finger over a portion of the interface. In an example, the capacitive interface 3500 may additionally or alternatively be configured to respond to "touch" inputs, such as momentary finger presses at one or more locations on the surface of the capacitive interface 3500. The speed, position, force, or other characteristic of the user input to the interface may be used or interpreted by the system 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 (such as may be received from a capacitive interface 3500). In an example, as the position of the input body 3701 moves from left to right across the capacitive interface 3500, the amplitude of the first signal from the first electrode 3501 may decrease, e.g., corresponding to the contact area between the input body 3701 and a portion of the first electrode 3501. That is, when input body 3701 is positioned on the leftmost side of first electrode 3501, input body 3701 contacts a larger surface area of first electrode 3501 than when input body 3701 is positioned on the rightmost side of first electrode 3501. In the example of fig. 37, when input volume 3701 is located on the rightmost side of first electrode 3501, touch sensor or capacitive interface 3500 records or measures the minimum capacitance indicated by capacitance signal 3703. In contrast, the example shows that when the same input body 3701 is moved from left to right, an increasing second signal may be provided by contact with the second electrode 3502, which in turn may correspond to a decreasing second capacitance signal 3702.

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

Fig. 39 generally illustrates an example 3900 of the relationship between an input gesture at the capacitive interface 3500 and the spool position 3901. In example 3900, when input body 3701 provides an input gesture, such as a slide, 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 reached. In examples, sliding in the opposite direction may cause the lacing engine 110 to decrease in tightness, e.g., by discrete amounts, or, for example, a single right-to-left slide may be used to fully unwind the spool or return the lacing engine 110 to the original position. Thus, a rolling input action of the input body 3701 at the capacitive interface 3500 may initiate a similar "rolling" spool or unwind at the lacing engine 110. In an example, the sensitivity of the scroll input or bobbin response may be adjustable or may be related to the speed at which the input body 3701 is moved through the capacitive interface 3500.

In an example, the capacitive interface 3500 incorporates or includes a touch sensor for use with a footwear system. Touch sensor can include first electrode 3501 and 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 user body input that electrically shunts the electrodes via contact between the user body and the electrodes. For example, the electrodes may be disposed in sufficient proximity to one another such that a user's finger or fingertip may electrically or capacitively bridge the electrodes to affect a measured or sensed electrical characteristic between the electrodes.

The touch sensor may be configured to receive user body inputs at different locations along the 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 inputs. For example, when a user body input is provided at a first location on the sensor, the surface area of the first electrode that the user body input contacts is larger than the second electrode, and as a result, a first electrical characteristic or signal value may be measured. When the user body input is provided at a different second location on the sensor, the surface area of the first electrode that the user body input contacts is smaller than the second electrode, and as a result, a second electrical characteristic or signal value may be measured. The first and second electrical characteristics or signal values may be used to distinguish or identify the 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.

Notes and aspects

Various aspects of the present disclosure may help provide solutions to the problems identified herein related to active footwear interfaces.

In an example, aspect 1 may include or use a subject matter, such as an apparatus, system, or device, that 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 activity 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 subsequent values 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 with, 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 an activity 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 a foot to a foot presence sensor inside an article of active footwear.

Aspect 5 may include or use, 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 can include or use, or can optionally be combined with the subject matter of one or any combination of aspects 1-5, to optionally include receiving the 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 use, 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 use, 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 the 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 use, 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 pattern of the active footwear.

Aspect 10 may include or use, 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 processor circuitry, wherein the processor circuitry 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 unconstrained.

Aspect 12 may include or use, 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 use, 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 a 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 of a user's body to the sensor.

Aspect 14 may include or use, 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 an example, aspect 15 may comprise or use a subject matter such as a device, system, or apparatus, which may comprise an article of activity footwear. Aspect 15 may include a user input configured to receive a user command and in response provide a command signal indicative of the user command, a lacing engine configured to tighten or loosen 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 use, or may optionally be combined with the subject matter of aspect 15, to optionally include a 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 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 a lacing engine based on an amplitude difference between a subsequent value of the command signal and an 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 changes in moisture content in the footwear, an activity sensor configured to provide a calibration indication in response to a detected user pattern 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 an example, aspect 20 may include or use subject matter such as a device, system, or apparatus that may include using a method for avoiding false triggering from a capacitive sensor of an article of footwear, where the capacitive sensor is configured to generate a footwear control signal based on the presence, absence, or proximity of a user's body relative to the capacitive sensor. In aspect 20, the method may include generating, by the capacitive sensor over time, a footwear control signal based on the presence, absence, or proximity of the user's body relative to the capacitive sensor, determining, over time, a correspondence between the specified sensor behavior model and one or more of: an amplitude characteristic, a morphology characteristic, or a rate of change characteristic of the footwear control signal, and disabling or enabling an automatic lacing or unlacing 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 magnitude over the 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 unbelting functionality of the footwear may be based on the footwear orientation information and the determined correspondence.

Aspect 23 may include or use, 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-on or footwear-off event.

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

In an example, aspect 25 may include or use subject matter such as a device, system, or apparatus that may include or use an interface system for footwear, e.g., subject matter of one or any combination of aspects 1-24 may optionally be provided separately. In an example, aspect 25 may include an interface system for an article of active 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, the user touch input bridging at least two electrodes, and the sensor may be configured to receive the user touch input at a plurality of locations along a length of the sensor. Aspect 25 may include a measurement circuit configured to measure a capacitance indicative signal from two or more electrodes, and the capacitance indicative signal may include information about a 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 indicating signal and, in response, provide a corresponding control signal to a lacing engine of the article of activity footwear to tighten or loosen the article of activity 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 indicating signal and, in response, calibrate a foot position sensor of the article of active footwear.

Aspect 28 may include or use, 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, including spaced apart substantially planar electrodes.

Aspect 29 may include or use, or may optionally be combined with the subject matter of aspect 28, to optionally include substantially planar electrodes that are similarly sized 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 oblique sides.

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 measurement circuitry to measure changes in capacitance indicative signals from at least two electrodes, and the changes are indicative of gestures or movements of a user touch input along or proximate to the touch sensor.

Aspect 33 may include or use, or may optionally be combined with the subject matter of aspect 32, to optionally include a change in a capacitance indicating signal indicative of a swipe gesture performed by a user along a length of the sensor.

Aspect 34 may include or be used with, 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 a magnitude of the desired change in the tightness of the footwear.

Aspect 35 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 25-34, to optionally include a location of a user touch input on the sensor that corresponds 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, aspect 37 may include or use a subject matter, such as an apparatus, system, or device, which may include or use a footwear system, including: a lacing engine configured to tighten or loosen the article of footwear in response to a control signal; a processor circuit configured to generate a control signal; a housing configured to enclose at least a portion of the strap 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 a 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 and spaced apart from one another.

Aspect 39 may include or use, or may optionally be combined with the subject matter of aspect 38, to optionally include a processor circuit configured to generate a control signal based on a position of a user input to the touch sensor.

Aspect 40 may include or use, 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 a 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 size and triangular shape.

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 a touch sensor disposed at one or more of a tongue, an outsole, a toe area, or a heel area of the article of footwear, and the touch sensor may be electrically coupled to the processor circuit.

Aspect 44 can include or use, or can 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 sidewall 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 use, or may optionally be combined with the subject matter of one or any combination of aspects 37-45, to optionally include a touch sensor comprising a capacitance sensor configured to measure a capacitance between two or more electrodes, and a magnitude of the capacitance varies in accordance with a 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 segment or length of the sensor using a user's body.

In an example, aspect 48 may include or use a theme such as an apparatus, system, or device 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 elongated electrodes substantially adjacent and spaced apart along a 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 wherein the sensor is configured to receive the 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 elongated electrodes as substantially right triangular, planar electrodes that are adjacent to each other at or along their hypotenuses.

Aspect 50 may include or use, 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 elongated electrodes having different conductivity characteristics.

Aspect 51 may include or use, or may optionally be combined with the subject matter of one or any combination of aspects 48-50, to optionally include that a surface area of a first electrode contacted by a user's body input is larger than a second electrode when the body input is disposed at a first location on the sensor, and that a surface area of the first electrode contacted by the user's body input is smaller than the second electrode when the body input is disposed at a second location on the sensor.

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 description. The drawings show, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are also referred to herein as "examples". Such examples may include elements in addition to those shown or described. However, the inventors also contemplate providing examples of only those elements shown or described. Moreover, the inventors also 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 (or one or more aspects thereof) shown or described herein.

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

Unless the context indicates otherwise, geometric terms such as "parallel," "perpendicular," "circular," or "square" are not intended to require absolute mathematical precision. Rather, such geometric terms are susceptible to variation as a result of manufacturing or equivalent function. For example, if an element is described as "circular" or "substantially circular," that description still encompasses components that are not exactly circular (e.g., elements that are slightly oblong or polygonal).

The method examples described herein may be machine or computer-implemented at least in part. 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 above examples. Implementations of such methods may include code, such as microcode, component language code, high-level language code, and the like. Such code may include computer readable instructions for performing various methods. The code may form part of a computer program product. Further, in an example, the code can be tangibly stored on one or more volatile, non-transitory, or non-volatile tangible computer-readable media, e.g., 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., compact disks and digital video disks), magnetic tape, memory cards or sticks, Random Access Memories (RAMs), Read Only Memories (ROMs), 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, as would be apparent to 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 foregoing detailed description, various features may be grouped together to simplify the present disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following 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 each other 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 activity footwear, the interface system comprising:

a touch sensor comprising two or more electrodes spaced apart and configured to receive a 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 a capacitance indicative signal from the two or more electrodes, wherein the capacitance indicative signal includes information about a location of the user touch input on the sensor.

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

3. The interface system of claim 1, further comprising a processor circuit configured to receive the capacitance indicating signal and, in response, calibrate a foot position sensor of the article of athletic 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 similarly sized 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 properties.

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 indicating signal from the at least two electrodes, wherein the change indicates 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 indicating signal indicates a swipe gesture along a length of the sensor.

10. The interface system according to 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 a magnitude of a desired change in tightness of the footwear.

11. The interface system according to claim 1, wherein the location of the user touch input on the sensor corresponds to a desired magnitude of 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 electrically couples 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 a 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 communicatively coupled with the processor circuit and configured to receive user input, wherein the user input electrically couples the two or more electrodes via a user's body;

wherein the processor circuit is configured to generate the control signal based on the user input.

14. A footwear system according to claim 13, wherein the two or more electrodes are elongate, substantially planar structures disposed at least partially adjacent to one another and spaced apart from one another.

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

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

18. A footwear system according to claim 13, wherein the two or more electrodes have respective different conductive characteristics.

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

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

21. A footwear system according to claim 13, wherein the two or more electrodes include flexible electrodes disposed on a flexible substrate.

22. A footwear system according to 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. A footwear system according to claim 13, wherein the touch sensor is configured to receive user input including a slide gesture that electrically couples the two or more electrodes through a segment 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 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.

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

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

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