MXPA02007362A

MXPA02007362A - Safety interlock for mechanically actuated closure device.

Info

Publication number: MXPA02007362A
Application number: MXPA02007362A
Authority: MX
Inventors: Stephen A Hawley
Original assignee: Prospects Corp
Priority date: 2000-01-31
Filing date: 2000-08-25
Publication date: 2002-12-09
Also published as: WO2001056142A8; JP2003520976A; WO2001056142A1; CA2398943A1; EP1266444A1; EP1266444A4

Abstract

An object detection system employs an optical triangulation module for detecting the presence of an object within a pinch zone of an automated closure device such as a power sunroof (22), power window, powered door of powered hatch. The optical triangulation module includes an emitter (160) and a position sensitive detector (166).

Description

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SECURITY INTERFACE FOR MECHANICALLY POWERED CLOSURE DEVICE BACKGROUND OF THE INVENTION 5 The present invention relates to security circuits and more particularly to a method and apparatus for providing an indication of the presence of an object • within a constriction zone located in the vicinity of an automated closing device such as a mechanical window, mechanical sunroof, mechanical door or removable roof. Closures for openings such as windows • for vehicles, sliding roofs and sliding doors are now commonly powered. As a convenience for 15 an operator or passenger of a vehicle, the mechanical windows are often provided with control features for automatic closing and opening of an opening after a simple short command of the operator or passenger. Alternatively, automatic closing and opening ^ 20 of an opening may be in response to the input of a separate device, such as a rain and temperature sensor. For example, a driver's side window can be commanded to lift from any lowered position to a fully closed position simply to the 25 momentarily raise a portion of the control switch from the window, then releasing the switch. This is sometimes referred to as a "quick close" feature. This feature is also commonly provided in conjunction with vehicle sunroofs. 5-car manufacturers can also provide these features along with mechanical doors, removable roofs or the like. fl Automatic opening closing features can also be used in various other local or industrial establishments. 10 In addition to providing added convenience, however, such characteristics introduce a security hazard not previously encountered. Body parts or inanimate objects may be presented within an opening when a command is provided to close automatically 15 the opening. For example, an automatic window closing feature can be activated because rain hits an interconnected rain sensor while a pet in the vehicle has its head outside the window. An additional example includes a child who has 20 placed his head through a window or sunroof that is activated to close by the driver, another passenger or accidentally by the child. In order to avoid potentially tragic accidents or characteristic damage involving objects 25 interposed trapped by mechanical windows or ceilings rt - sliding, the systems that have been developed detect the circumstances in which a window has been commanded to close quickly, but the closing has not occurred within a given period of time. As an example, a system can monitor the time a window takes to reach a closed state. If a temporary threshold is exceeded, the window is automatically lowered. Another system monitors the current consumption attributed to the motor that operates the window. If it exceeds a threshold at an inappropriate time during the closing operation, the window is redisplayed. The problem with such safety systems is that an interposed object must first be trapped and subjected to the force of closing the window or other closing device for a discrete period of time before the safety mechanism lowers the window or inverts on the roof. sliding or other closing device. Injury or personal injury to property can still occur in such systems. In addition, if a mechanical failure in the window drive system occurs or if a fuse is blown, the person or object may remain trapped. Non-contact object detection systems are known which detect the presence of an object interposed within an opening area. Such systems are used, for example, with security systems and circuits tálÁi, tiiftÉft¿ ^ security door security for garage, to detect the interruption of the beam of light through an opening. Other systems are used with automotive openings that have motorized closing members such as windows, sunroofs and sliding doors, to detect an interposed object proximate or extending through the respective aperture. Undesired operation of an opening closing member is therefore prevented when an interposed object such as a finger or an arm extends through the opening during closing; the closing member is not required to contact the interposed object so that the object is detected. Such object detection systems typically measure the magnitude of a reflected signal to determine the presence or absence of an interposed object. An emitter emits a beam of light that is directed through the opening to an opposite side of the aperture. An uninterrupted aperture results in the reflection of at least a portion of the beam emitted from the opposite side of the aperture. A receiver arranged near the emitter receives the reflected light beam and generates an output signal indicative of the intensity of the reflected beam. The reflection on the opposite side ordinarily results in a reflected signal of a nominal intensity that is returned to the receiver. An interposed object located in the path of the light beam ftL.tmi??. ** l *** i *?, - * .. tl? ~. *.? * ..... "tiiMir IT? t,? ... a >, s ^ .?,.? S i ^ j,? Ki ^ ?? t ^ ^ f ^ ms £ ^ i ^? ^^^ 1 changes the intensity of the reflected light beam, a condition reflected in the output signal of the detector. The output signal of the detector with an object in the path of the light beam will thus differ from the output signal of the detector in the absence of an object, depending on the reflectivity of the interposed object and the flp reflection characteristics of the environment of the detector. opening, the output signal of the detector will be greater or less than the nominal output signal of the detector 10 Distance measurement triangulation sensors are known which are used to generate an output signal representative of the distance for an object. include, for example, distance measurement sensors Models Nos. GP2D02 and GP2D05 commercially available from 15 Sharp Microelectronics of the Americas, Camas, Washington USA. Such sensors, which are referred to herein as optical triangulation modules, include an emitter and an adjacent detector mounted in a common package. The detector used in a module is referred to as 20 a position sensitive detector (PSD) that provides a signal indicative of the location of the detector surface in which a reflected beam hits the PSD surface. The module is typically positioned so that the emitter emits a beam of light in the direction of a target 25 indicated. The beam of light is reflected off the lens signaled to hit the surface of the PSD. Since the distance between the emitter and the detector are fixed, the distance to the stated target can be determined by triangulation techniques based on the output signal obtained from the PSD. When the indicated target is closer to the module, the beam of light emitted by the emitter and reflected off the object will hit the PSD beyond the emitter. The optical triangulation modules have therefore been used for the detection of distances between the module and the indicated objective such as in focal systems within cameras. Therefore, it may be beneficial to provide a safety circuit that is capable of detecting the presence of an object in a constriction zone adjacent to an automated closure device to prevent a moving member from causing damage or injury to the person or property. .

COMPENDIUM OF THE INVENTION A method and apparatus for providing a signal indicative of the presence of an object within a constriction zone are described. The definition of the constriction zone varies depending on the nature of the automated closure device. For example, if the automated closure device comprises a member of Mechanically assisted slidable closure such as a mechanical sunroof, a mechanical window or a mechanical door, the constriction zone is defined by a leading edge of a closing member and a portion of the opening defining a terminal portion of the opening that opens with the leading edge of the closure member. If the closing device comprises an articulated, mechanical or removable roof door or a mechanical revolving door, the constriction zone is generally a plane defined by an edge of the opening reached by the front edge of the removable door or roof and an adjacent line at the opening edge in the trajectory of the front edge trip of the removable door or roof. In an embodiment in which the closure member comprises a slidable closure member, an optical triangulation module having an emitter and a position sensitive detector (PSD) is selectively positioned adjacent the plane of the slidable movement of the closure member of the closure member. Thus, the emitter of the module emits an infrared beam (IR) that passes through the constriction zone and reflects from a reflective surface on the opposite side of the constriction zone to the PSD inside the module. The IR light beam strikes the surface of the PSD at a nominal position in the absence of an object within the constriction zone. In the case of an object that is present '~ f within the constriction zone within the beam path of the IR beam emitted, the IR beam is reflected off the object to a different position in the PSD. The PSD provides an output signal that is analyzed to provide an indication of the presence of an object within the constriction zone. The output signal can be used to stop movement of the mechanical closure member, reverse the movement of the mechanical closure member, activate an alarm or some combination of these. In another embodiment, the optical triangulation module is positioned adjacent to the constriction zone of a removable mechanical roof, mechanical hinged door or revolving door. More specifically, the module is selectively positioned so that the emitter emits a beam of IR light that passes through the constriction zone and, as discussed above, in the absence of an object within the constriction zone. , is reflected from a reflective surface on the opposite side of the constriction zone to a nominal location on the surface of the PSD in the absence of an object 0 within the constriction zone. In the case of the presence of an object within the constriction zone, the light beam emitted by the emitter module is reflected out of the object at a different position on the surface of the PSD. In response to the detection of the difference in the PSD output signal, 5 the movement of the mechanical door or removable roof, ^ .. «aa ^^, ^ ... ^, ^. ^^ ..... ^ .. ^^^ a, may be stopped or reversed as applicable. Additionally, to provide greater reliability in the detection of objects within the constriction zones of the automated closure devices discussed above, an IR reflected amplitude detection system may be employed in combination with the optical triangulation module. The IR reflected amplitude detection system includes an IR emitter and an IR amplitude detector positioned adjacent to the emitter and preferably in a common housing. In one embodiment, the IR reflected amplitude detection system shares a common housing with the optical triangulation module. The IR emitter emits a substantially flat beam of light which, in the absence of an object within the constriction zone, is reflected from one or more reflective surfaces on the opposite side of the constriction zone and again to the IR amplitude detector. In the event that an object is introduced into the path of a light beam emitted by the IR emitter, a change in the amplitude of the received IR light beam is detected by the IR amplitude detector. The output of the IR amplitude detector is analyzed or subjected to the threshold to provide an indication of the presence of an object within the constriction zone. As a result of the detection of the presence of an object within the constriction zone either by the IR amplitude detector or the * ** ^ l ^ m ^ m ************. * »***.

PSD, or both, the movement of the mechanical seal member may stop or reverse, and / or an alarm may be generated. The system described today can also be used for intrusion detection. For example, if the closure is a mechanical window and automatic ventilation is allowed even if the vehicle is parked, it may be possible for someone to attempt unauthorized entry to the vehicle through the partially disabled vehicle, or to insert an object through the window open for the purpose of uncoupling a door lock. Monitoring under these circumstances can be continuous or periodic, the latter has the advantage of consuming less energy. Other aspects, features, and features of the present invention are described in the detailed description that follows.

BRIEF DESCRIPTION OF THE DIVERSE VIEWS OF THE DRAWINGS The invention will be more fully understood with reference to the following detailed description together with the drawing, of which: Figure represents a top view of a sliding roof employing an object detection system according to the present invention in which the sunroof is shown in an open position; Figure lb is a cross-sectional view J-a * um '- * > - * - * < *. • * * ***** .. * lateral of the vehicle roof of Figure la along section line BB and closing towards the front of the vehicle; Figure 1c depicts a top view of a sunroof employing an object detection system according to the present invention in which the sunroof is shown in a closed position; Figure 1 is a schematic diagram illustrating the theory of operation of an optical triangulation module as employed in the presently described invention; Figure 1 is a block diagram of the optical triangulation module as used in the presently described invention; Figure 2a is a side view of a vehicle window illustrating the use of an optical triangulation module for detecting objects within a constriction zone along the upper region of the vehicle window opening; Figure 2b is a side view of a vehicle window illustrating the use of an optical triangulation module for detecting objects within a constriction zone along the front region of the vehicle window aperture; Figure 2c is a side view of a vehicle window illustrating the use of multiple optical triangulation modules for the detection of objects within the constriction zones along the front and top regions of the vehicle window opening; Figure 2d is a side view of a vehicle window illustrating the use of an optical triangulation module for detecting objects along a diagonal extending from the lower front corner of the window opening to the corner upper rear of the window opening; Figure 3a is a partial side view of a van illustrating the use of an optical triangulation module arranged in a "B" column for detection of objects within a constriction zone of a sliding door opening; Figure 3b is a partial side view of a van illustrating the use of an optical triangulation module disposed at a leading edge of a sliding door for the detection of objects within a constriction zone of a sliding door opening; Figure 4a is a perspective view illustrating the use of an optical triangulation module for the detection of objects within the constriction zone of an articulated door; Figure 4b is a side view illustrating the use of an optical triangulation module for the detection of objects within the constriction zone of a roof - • • fcei- - »- '• -" -' • «» • --- 'gg ^ 2a ^ HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH optical triangulation for the detection of objects within the constriction zones of a revolving door, and Figure 5 is a top view illustrating the use of an optical triangulation module together with an amplitude detection system for the detection of objects within the constriction zone of the sliding roof of a vehicle.

DETAILED DESCRIPTION OF THE INVENTION A method and apparatus for detecting the presence of an object within a constriction zone of an automated closure device such as a mechanical sunroof, mechanical window, or a mechanical door or removable roof is described. In each of the embodiments described herein, an optical alignment sensor is used to provide an indication of the presence of an object within a constriction zone of the automated closure device. In response to the indication of the presence of an object within the constriction zone, the movement of the automated closure device may be stopped or reversed to decrease the likelihood of personal injury or property damage that it may result if the closing device continues movement through the constriction zone. In another embodiment of the invention, a reflected IR amplitude sensing system is employed in conjunction with the optical alignment sensor to improve the probability of detection of an object within the constriction zone of the automated closure device. A mechanical sunroof is illustrated in Figures la-lc together with an optical triangulation module.

With reference to Fig. 1, a car roof 10 has an opening 12 defined by a closing edge 14, first and second side edges 16 and 18, and a rear edge 20. A sliding roof panel 22 can be slidably moved within the roof 10 between an open position (see Figure 15 la) and a closed position (See Figure 1). In the open position, the sliding roof 22 retracts into the roof 10 to allow fresh air and daylight to enter the vehicle and in the closed position, the sliding roof 22 seals the opening in a conventional manner. A constriction zone for the illustrated closure device can be defined by the closing edge 14 of the opening 12, portions of the opening 12, sides 16 and 18 respectively, and a line AA located at a predetermined distance back from the edge 14. closing. This The distance can be selected to allow an object 30 such as a human head to pass through the constriction zone between the edge of the closure and the line AA. It is desirable to detect the presence of objects within the constriction zone and the closure of the sunroof 22 when the 5 objects are present within this zone to decrease the likelihood of personal injury or damage to property if the children's heads or limbs or pets, or portions of object, extend through the sliding roof 22 when the sliding roof control mechanism is activated for 10 closing the sliding roof 22. To detect the presence of an object 30 within the constriction zone, a triangulation module 32 • Optical is mounted below the travel plane of the sliding sunroof, as shown in Figure lb. He The optical triangulation module 32 includes an IR infrared emitter 34 and a position sensitive detector 36 housed in a common package. The module 32 is selectively mounted adjacent to an edge of the constriction zone below the travel plane of the sunroof 22. The cladding 20 of the vehicle roof in this location is preferably adapted to receive the module 32 while decreasing abrupt projections. In an alternative embodiment, the emitter 34 and the detector 36 are arranged in discrete housings. 25 In the absence of an object within the area of When the constriction is constricted, a beam 38a emitted by the emitter 34 crosses the constriction zone and collides on a reflector 40 conformably mounted below the travel plane of the sunroof 22 in the opposite side of the constriction zone. The emitted beam 38a is reflected out of reflector 40 and collides with the position sensitive detector 36 in a first location. With reference to Figure ld, the operation theory of the optical triangulation module 34 is described. An IR diode emits a modulated beam which is focused by optics such as an immediate lens emitter. The beam impacts an object and a portion of the light is reflected back through the optics of the receiver to the PSD. In one embodiment, PSD is understood as a photodiode arrangement. Because object A is closer to the emitter, the light reflected from it enters the PSD lens at a greater angle that illuminates the distant object B. When the light hits one of the photodiodes, the current flows proportional to the photodiode of which it illuminates. The output current is compared to the threshold levels, and a voltage proportional to the illuminated location on the photodiode array is generated. Reference is made to a predetermined correspondence between the output voltage and the distance of the object in order to be able to resolve the distance to the reflecting object. However, in the present application, there is no need to resolve an absolute distance. Rather, the only determination to be made is whether the object of reflection is closer to the triangulation module than the unobstructed aperture environment, which may include the reflector arranged opposite to the module. In a further embodiment, the test for an obstruction may be if the reflected light energy is from an object at any distance greater or less than that of the unobstructed reflector. In the event that an object 30 enters the constriction zone and obstructs the region only below the plane of travel of the sunroof 22, the beam 42a emitted is reflected off the object 30 and the reflected beam 42b collides with the surface of the detector 36 responsive to the position in a location different from the first location. The output signal of the position-sensitive detector is presented to the comparison logic (discussed in the following with a description of FIG. 1) and the comparison logic generates a signal indicative of the presence of the object 30 within the zone. of constriction if the comparison logic input signal differs from the nominal PSD output signal by a predetermined value. More specifically, when the object 30 is interposed within the path of the light beam, the PSD within the optical triangulation module 32 will typically generate an output signal which may indicate a distance to the object smaller than the distance to the reflector 40. An obstacle that simply blocks the beam 42a emitted or that is so close to the module 32 that it is effectively outside the field of view of the detector 36 will result in an indication of the module 32 that no valid distance signal was received. This can be interpreted as being indicative of the presence of an obstacle. In the generation of an output signal from the comparison logic indicating the presence of an object within the constriction zone, the actuator causing the movement of the sliding roof 22 is controlled to stop the closing of the sliding roof 22. In addition, an alarm may be provided to alert the driver and passengers to the existence of the object 30 within the constriction zone. The movement of the sliding roof can also be reversed in one mode. A block diagram illustrating the drive logic of the emitter and the comparison logic employed in the object detection system currently described is shown in FIG. With reference to Figure 1, a signal generator 50 generates the appropriate control signal for the triangulation module 55. This signal causes the LED unit 54, responsible for an internal control circuit 52, to illuminate the associated LED. The reflected energy of an object hits a photodiode of PSD 56, causing ^ A i? Xk? ^? ^ That a characteristic output is presented to the signal processing circuitry of the PSD 56. This output can be further processed by the internal control circuit 52 before moving on to the logical external comparison 51. Depending on the device 55 used, the performance can be a series of pulses that characterize the distance of the reflective object explicitly from the device 55, or it can be a binary logical performance indicative of whether the reflective object is beyond a certain distance from the device 55 or do not. The logical external comparison 51 that may have a discrete memory (not shown) associated with it, compares the data received from the device 55 and provides an output indicative of whether the reflected light energy is from an obstacle or from a reflector arranged in a opposite side of an opening that is monitored. If a device 55 such as the Sharp GP2D05 is used, the internal signal processing circuit 56 can be programmed to provide a certain output if the reflective object is less than a certain distance from the device 55, thereby potentially obtaining the need for logic 51 of external comparison. The signal generator 50 and the comparison logic 51 can be discrete circuits, or they can be realized through the use of a programmable microprocessor and associated memory (not shown). Figures 2a-2d illustrate modalities tm ^ im? É? iiÉ alternatives in which the automated closure device comprises an automotive mechanical window and one or more optical triangulation modules which are used to detect the presence of an object within one or more respective constriction zones of the window. As shown in Figure 2a, a single optical triangulation module 100 is used to detect the presence of an object within a constriction zone along the top region of the window opening. The module 10 100 is mounted inside the vehicle and is selectively positioned so that an emitter 110 emits a beam that crosses the constriction zone. The emitted beam is reflected by a reflector 104 (also mounted inside the vehicle) to the PSD 106 housed within the optical triangulation module 100. The The operation of the system for detecting an object within the constriction zone along the upper region of the window opening is otherwise described as above with respect to Figures 1-ld. The reflector 104 can be comprised of any material that 20 results in the reflection of a substantial portion of the IR beam emitted to the PSD 106. It may be a discrete reflective element, it may be an integral part of the interior panel of the vehicle or it may simply be the panel itself. These variants in the realization of the reflector apply to all 25 embodiments described herein.

As shown in Figure 2b, an optical triangulation module 110 and a reflector 112 can be mounted within a vehicle to detect objects in a constriction zone along the front region of the window opening. In addition, as shown in Figure 2c, multiple optical triangulation modules 120 and 122 may be employed in conjunction with respective reflectors 124 and 126 to provide a higher probability of object detection within both the upper and frontal regions of the constriction zone of the opening of the window. It should be noted that the positions of the modules and reflectors can be reversed. Finally, as illustrated in Figure 2d, an optical triangulation module 130 is mounted within the vehicle adjacent to the lower front portion of a window opening and a reflector 132 mounted within the vehicle along the upper rear region of the vehicle. window opening to attempt to detect, with a single detection system, objects in the constriction zone along the front region of the window opening or the upper region of the window opening. As illustrated in Figure 3a, an optical triangulation module 140 can be mounted within a vehicle along an upper edge of an opening of the sliding door 142, close to a vehicle "B" column, so that a transmitter within module 140 emits a beam of IR light crossing a constriction zone along the front region of the opening 142 of the door. The beam of light emitted hits a reflector 144 mounted inside the vehicle on the opposite side of the door opening 142 so that the reflector 144 reflects the light beam emitted again to a position sensitive detector within the housing of the module 140. The process of the output signal of the position sensitive detector is performed as described in the foregoing together with Figures la - lc. Figure 3b illustrates the positioning of the optical triangulation module 140 at the leading edge of a sliding door 142. As the door is processed, the beam of light emitted hits a reflector 144 mounted inside the vehicle at the lower edge of the door opening so that the reflector 144 reflects the light beam emitted again to a position sensitive detector. within the housing of the module 140. The processing of the output signal of the position-sensitive detector is performed as described in the foregoing together with Figures la-lc. Other placements for the module 140 in relation to the opening of the door are possible. For example, one or more optical triangulation modules 140 can be arranged in the "C" column to emit the light towards the column?, B "and to receive reflected light from it.If several modules are used in this mode, only one Processing element can be used to detect an obstacle, since the knowledge that the module detected an obstacle is irrelevant. As illustrated in Figures 4a-4c, an optical triangulation module 150 may be employed in conjunction with a reflector 152 to detect the presence of an object within the constriction zone of an articulated, mechanical door 154, a removable mechanical ceiling 156, or a mechanical rotating door 158. In contrast to the embodiments of Figures la-lc, 2a-2d and 3a-3b, the closure in these situations comes out of the plane of the opening. In the case of the mechanical removable roof 156, the reflector (not visible) is disposed on the opposite side of the constriction zone of the optical triangulation module 150. Similarly, with respect to the top view of the rotating door 158, the reflector is disposed on the opposite side of the constriction zone of the optical triangulation module 150 and therefore is not visible in the top view. It should be appreciated that in all embodiments, the position of the optical triangulation module and the reflector can be reversed, however a greater signal to noise immunity can be achieved by positioning the optical triangulation modules on a particular side of the respective constriction zone. To increase the probability of detecting an object within a constriction zone of a device of automated closure, including the devices described in the foregoing, a reflected IR amplitude detector may be employed in combination with the optical triangulation module. More specifically and with reference to Figure 5, 5 a signal generator (not shown) is used to drive an IR emitter 160 at a designated frequency. The emitter # 160 is selectively positioned so that a beam 162a of substantially flat light emitted from the IR emitter 160 crosses at least a portion of the constriction zone and strikes the interior of the vehicle. Potentially including the opening panel, on the opening 12 of the sliding roof. A discrete reflector 164 may be provided to increase the energy of the reflected signal in the absence of an obstacle. Without any object in the light path, the aperture environment or alternatively the reflector 164 reflects at least a portion of the beam 162 of emitted light (reflected portion not shown in Figure 5 for simplicity) to a localized IR detector 166. adjacent to the emitter 160. The IR detector 166 generates an output signal 20 indicative of the absence or presence of an object within the light path of the emitter 160 to the detector 166. For example, the magnitude of the detector 166 of the signal of Output may vary with the received signal resistance. Alternatively, the detector output signal can be provided as a series of pulses that vary in the IHflJMÍMÉÍE -1 1,; l | l¡l ^ «. ^^^^ > ^ fa. ^ * < He was "^ ^ ^" «i ^ ^ ^ ^ ^ ^. A._j. __ »» ,. g ^., 'number, period or length as the received signal varies. In the event that an object is present in the field of the light beam 162 emitted, the amplitude of the reflected signal outside the object is likely to vary based on the size, orientation and reflectivity of the object. A variation in the output signal of the IR detector 166 observed in the absence of an object may be indicative of the presence of an object within the illuminated region of the aperture 12. With the detection of the variation 10 at the output of the IR detector 166, a control signal is generated to stop the movement of the automated closing device. The movement of the closing member can be stopped immediately with the detection of an object within the illuminated field or, alternatively, only when the edge 15 front of the closure member enters the constriction zone and an obstacle is detected. Additionally, movement of the movable member of an automated closure device can be stopped with the detection of a signal, indicating the presence of an object within the area of 20 constriction, received from an optical triangulation system or the IR amplitude detection system. The IR amplitude detector 166 of Figure 5 generally comprises a photodiode and a filter and processing circuitry including a memory. The photodiode is the 25 responsible element for reflected IR radiation, and typically generates an output proportional to the amplitude of the reflected radiation that hits it. The filter and the processing circuitry apply the filtering to the output signal of the photodiode to improve the signal-to-noise ratio. Additionally, the processing circuitry includes the amplitude threshold based on a threshold or thresholds stored in the associated memory. The thresholds thus applied can be static, or they can be adjusted dynamically according to the previous measurements of reflected energy in the absence of an obstacle. As noted previously, the recognition of an obstacle may be the result of a decrease in reflected energy when the environment of the aperture is highly reflective or of an increase in reflected energy when the environment of the aperture is absorbing the IR energy. . The positioning of the emitters and detectors for the currently disclosed IR amplitude detection system may be as shown for the notification of the optical triangulation detection system, however, that the detector in the IR amplitude detection system is measuring the amplitude of the received light beam instead of a location on the surface of a position-sensitive detector. It should also be noted that with the detection of an object within the constriction zone of any of the above-described automated closing devices that have been activated to close, movement of the closure member can be stopped immediately with the detection of the object within the constriction zone or, alternatively, only when the leading edge of the closure member enters the zone of constriction. Furthermore, it should be noted that the combined optical triangulation detection system and the IR amplitude detection systems illustrated in Figure 5 can be employed in conjunction with any of the automated closure devices previously described. In addition to the use of the currently described detector to prevent the capture of an object by a mechanical device, it can also be used as part of an intrusion detection system. For example, a vehicle that has mechanical windows can be provided with an automatic ventilation system. Such a system automatically opens the windows or a sliding roof or predetermined mounting to allow the hot internal air to be vented out of the vehicle. Depending on how far these closures are opened, an intruder may be able to insert a hand or other object into the vehicle for the purpose of removing a valuable item or opening a vehicle door to enter. The previously described system can be used to continuously monitor the opening once the ^ 1 ^^, (££ £ jMaa | Í! Í s * "automatic ventilation has been started.If an object is detected, an alarm can be heard, or depending on the mode, the mechanical seals can be commanded to close. The last option should take into consideration the potential to cause damage to either the intruder or the interposed object.The response to detection may also include disabling a vehicle ignition system or the automatic communication of an inaudible alarm signal to a remote receiver. The duty cycle for the detection system in this mode may be less than in conjunction with the detection of obstacles for the normal closing operation in order to conserve battery power.As an alternative to the use of an IR alignment system such as describes through the above and as illustrated in Figure 1d, other technologies can be used, for example, it is possible to replace the IR amplitude detection system with an Ultrasonic system: An ultrasonic energy-based alignment detection system provides a measurement of distance to an object in its beam path by measuring the short time intervals between the transmitted and reflected bursts of ultrasonic sound. Depending on the specific application, the wide and narrow beam units can be used, with detection ranges that are approximately two inches to three feet. As with the IR alignment system, the ||| Jj | Í? What is it? -filfa? «*» * - n ^^ t- ^ -.- .. «- ^^ - * ^. .- ^. ^^ Absolute margin for an object may not be necessary. Rather, the deviation of the reflection surface from a distance to another distance can be used as a cause to recognize the presence of an object. In a further embodiment, a thermal sensor may be used in place of an IR system. The temperature of the human body corresponds to an emission of the black body crest of 10 microns. A suitable sensor for this wavelength is of the pyroelectric type, which are often found in internal or external automatic light switches. In most pyroelectric radiation detectors, the radiation is absorbed by a thin electrode whose thickness can be adjusted to make the absorption higher than 50% for the entire electromagnetic spectrum. The resulting change in temperature to the electrode in the presence of a radiant object provides a corresponding change in the electrical output signal. The change in the electrical signal is compared by the associated processing circuitry against a range of expected values to produce a determination of whether or not there is an object in the target field. In yet another embodiment, an RF alignment system is used. Such a system consists of its simplest form of a transmitter, an antenna, a receiver and a signal processor. The transmitter is responsible for providing the electromagnetic energy, while the antenna works to concentrate the radiated energy into a shaped beam that points in the desired direction. A directional beam of RF energy is emitted through the region being monitored, which in the current application is the constriction zone. Objects within the beam reflect a portion of the electromagnetic energy back into the system. The antenna collects the energy contained in the echo signal and supplies it to the receiver. This returned energy is amplified by the receiver and then analyzed by the radar processor. The radar processor analyzes the echo to establish if an object is present. Those of ordinary skill in the art should further appreciate that variations and modifications of the methods described in the foregoing and apparatus for providing detection of objects in an opening in the path of a closure member can be made without departing from the inventive concepts described in the present. Accordingly, the invention should be viewed as limited only by the scope and spirit of the appended claims.

M. TO.? ^ Í * ÍJ. ± ^ --- * - * ** «*»

Claims

CLAIMS 1. An obstruction detection circuit for an aperture, comprising: an emitter for emitting radiation close to the aperture; a reflection surface to reflect at least a portion of the radiation emitted; and a receiver for receiving the reflected radiation, the receiver provides an output signal that depends on the position in the receiver that the reflected reflected light, if any. The circuit of claim 1, wherein the reflected radiation comprises at least a portion of the radiation emitted as reflected from the surface of 15 reflection. The circuit of claim 1, wherein the reflected radiation comprises at least a portion of the radiation emitted as reflected from an intermediate object to the emitter and the reflection surface. 4. The circuit of claim 1, further comprising comparison logic for receiving the output signal from the receiver and for comparing the output signal with a threshold value available for the comparison logic. 5. The circuit of claim 4, which also 25 comprises a memory unit in communication with logic comparison to store the threshold value. The circuit of claim 1, further comprising comparison logic for receiving the output signal from the receiver and / or for comparing the output signal with 5 a first set of acceptable values. The circuit of claim 6, further comprising ^ P comprising a memory unit in communication with the comparison logic to store the first set of acceptable values. 8. The circuit of claim 1, wherein the receiver comprises a series of photodiodes, each having a characteristic output when illuminated by radiation. • reflected. The circuit of claim 1, further comprising a controller, responsible for the output signal of the receiver, for controlling a mechanical seal adapted to seal the opening. The circuit of claim 9, wherein the controller is for controlling an adapted mechanical seal • 20 to slide inside the opening. The circuit of claim 9, wherein the controller is for controlling a mechanical seal adapted for articulated movement adjacent to the opening. The circuit of claim 1, wherein the emitter comprises an infrared wavelength emitter. ? ^ ea? a ± i ^. ^ ElfeM lg- ^ ii * .. ^^ 13. The circuit of claim 1, wherein the emitter is a light emitting diode. 14. The circuit of claim 1, wherein the receiver is a position sensitive detector. 15. The circuit of claim 1, further comprising: a second emitter for emitting a radiation plane close to the aperture; and a second receiver for receiving the reflected plane radiation, the second receiver provides an output signal dependent on the amplitude, in the second receiver, of the reflected plane radiation. 16. The circuit of claim 15, further comprising a controller, responsible for the output signal of the receiver and the second output signal of the receiver, for controlling a mechanical seal adapted to seal the opening. The circuit of claim 16, wherein the controller is responsible for the second output signal of the receiver when the second output signal of the receiver is indicative of a variation in the second reflected radiation of an expected range of amplitude values. The circuit of claim 16, wherein the controller is adapted to interrupt or inhibit the closure of the mechanical seal in response to the output signal of the receiver and the second output signal from the receiver. 19. The circuit of claim 1, wherein the receiver output signal is one of two possible values. The circuit of claim 19, wherein the first of the possible values is indicative of the reflected radiation that illuminates a position within a first range of receiver positions, and the second of the possible values is indicative of the radiation reflected that does not illuminate a position within the first margin of receiver positions. 21. A method for detecting an obstacle close to an opening having a mechanical closure operative therein, comprising: emitting, from an emitter, radiation close to a portion of the aperture; receiving at least a portion of the radiation emitted, as reflected from at least one surface near the aperture, in a receiver; and generating a position signal, through the receiver, indicative of the position in which the emitted radiation was received, reflected from the receiver, if any. The method of claim 21, wherein the further generating step comprises generating the position signal indicative of a distance from the receiver to an object that reflects the reflected emitted radiation. u * á6ái * t. *. * .. ^ ¿. ^^ a ^. 23. The method of claim 21, wherein the step of generating further comprises generating the position signal indicative of whether the emitted radiation was received, reflected in a first portion of the receiver. The method of claim 21, wherein the step of generating further comprises generating a position signal indicative of receiver failure to receive at least a portion of the emitted radiation. The method of claim 21, further comprising the step of determining whether the position signal is indicative of reception of any of the emitted radiation, reflected in the receiver. 26. The method of claim 21, further comprising the step of comparing the position signal with a 15 threshold value. The method of claim 26, wherein the step of comparing comprises comparing the position signal with a reflective threshold value of an acceptable distance from the receiver to an object reflecting the emitted radiation, 20 reflected. The method of claim 26, further comprising the step of controlling a mechanically actuated closure for opening in response to the comparing step. 29. The method of claim 21, which also Ü É É l l l i i i i i i i i i i:::: i: i emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit emit receiving at least a portion of the plane of radiation emitted, as reflected from the environment of the aperture, in a second receiver; and ^ P generating an amplitude signal, by means of the second receiver, indicative of the amplitude of the radiation plane emitted, reflected as received in the second receiver. The method of claim 29, further comprising the step of controlling a mechanically operated closure for opening based on the position signal and the amplitude signal. 31. A system for detecting a nearby obstacle and the opening can be sealed by a mechanical seal, comprising: a first emitter for selectively emitting a focused beam of light energy close to the aperture; a first receiver for receiving at least one portion of the focused beam emitted, reflected from one or more reflection surfaces close to the aperture and for generating a first output signal indicative of a location on the first receiver in which the focused beam , reflected was received; and 25 a controller to control the mechanical seal in "*** - -" - "-" ^ ¿^^^^^ g ^^ gj ^ i ^ [^ ¡? ^ Answer to the first exit. The system of claim 31, wherein the first receiver is furthermore to not receive at least a portion of the focused beam, emitted with the reflected from any reflection surface close to the aperture and to generate a first indicative output signal of the failure to receive. The system of claim 31, further comprising: a second emitter for selectively emitting a flat beam of light energy close to the aperture; and a second receiver for receiving at least a portion of the flat beam emitted as reflected from one or more reflection surfaces close to the aperture and for generating a second output signal indicative of the relative strength of the reflected, flat beam received by the second receiver; where the controller is also to control the mechanical closure in response to the second output. 34. The system of claim 33, further comprising a memory in association with the controller for storing one or more threshold values for comparison by the controller against the first and second outputs. 35. The system of claim 33, wherein the first output is indicative of a relative distance between an object that reflects at least a portion of the beam. focused emitted and the first receiver. 36. The system of claim 35, wherein the controller is operative to stop, reverse or inhibit the movement of the mechanical seal if the relative distance is below a threshold value. 37. The system of claim 36, wherein the controller is operative to stop, reverse or inhibit the movement of the mechanical seal if the relative distance is below a threshold value and if the relative resistance of the reflected, flat beam is beyond a prescribed threshold value. 38. A method for detecting an obstacle close to an opening that can be sealed by a mechanical seal, comprising: emitting a focused beam of light energy close to the opening; attempting to receive a reflected portion of the focused beam at a location in a position sensitive detector; generating a first output signal indicative of the location in the position sensitive detector if the reflected portion of the focused beam is received; and comparing the first output signal with a threshold value to infer whether the reflected portion of the focused beam is reflected off an obstacle close to the aperture. 39. The method of claim 38, further comprising the step of generating the first output signal indicative of the failure to receive the reflected portion of the focused beam of the position-sensitive detector. 40. The method of claim 38, further comprising the step of selectively stopping, inverting or inhibiting the movement of the mechanical seal with response to the comparison step. 41. The method of claim 38, further comprising the steps of: emitting a flat beam of light energy close to the aperture; receiving a reflected portion of the plane beam in an amplitude sensitive detector; generating a second output signal indicative of the amplitude of the reflected portion as detected by the amplitude sensitive detector; and comparing the second output signal with a threshold value to infer whether the reflected portion of the plane beam is reflected off an obstacle close to the aperture. 42. The method of claim 41, further comprising the step of selectively stopping, inverting or inhibiting the movement of the mechanical seal in response to the steps of comparing the first and second output signals with the respective threshold value. ^ - ~ - * - * ~ ^ ¿-. ^. ^. ^^ t .. ^, ^ iA ... ^. ^^^ l ^^ ^