OBJECT DEFORMATION DETECTION USING CAPACITIVE SENSING

A deformable sensor may detect changes in capacitance due to relative motion of electrodes in the deformable sensor, or due to a proximate object. In some cases, a controller circuit may communicate with a motion interface system to alter motion of system components when a deformation or proximate object is sensed.

FIELD OF THE DISCLOSURE

This disclosure relates generally to using capacitive sensing to detect a potential pinching or crushing of an object, or to induce a motive response. More particularly, this disclosure relates to capacitive sensors in a gasket or other flexible material that may be mounted to a non-flexible material to detect potential pinching or crushing of an object by the non-flexible material, or to change the motion of a portion or component of the system.

BACKGROUND

Many non-flexible objects, such as vehicle doors, garage doors, refrigerator doors, hinged doors, windows, garbage can lids, other types of lids, shipping containers, other types of containers, sliding doors, gates, revolving doors, rotary objects, or the like, often present a pinching or crushing hazard for hands, fingers, or other objects. Additionally, many of these same non-flexible objects often include a flexible member, such as a gasket or other seal, that is used to provide a weather-tight seal. In existing devices, the flexible member typically has no function other than to seal the door or other non-flexible object. Thus, there is often no way to warn, prevent, or otherwise inhibit the pinching or crushing of an object that gets in the path of the non-flexible object or door when it is operating.

For existing systems that do include some type of crush or pinch detection it is often a separate system, such as an optical beam detector, or the like, that adds to the overall complexity and cost of the device. Other drawbacks, inconveniences, and issues with existing devices and methods also exist.

SUMMARY

Accordingly, disclosed embodiments address the above-noted, and other, drawbacks, inconveniences, and issues with existing devices and methods. In one disclosed embodiment there is provided a flexible or otherwise deformable sensor that comprises a flexible gasket. Embodiments of the flexible gasket house a number of electrodes. The electrodes are in communication with a touch controller circuit. The touch controller circuit communicates with a motion interface system that interacts with the moving parts upon which the deformable sensor is installed as outlined below. Other advantages, features, and methods of operation of the disclosed embodiments will be apparent to those of ordinary skill in the art having the benefit of this disclosure.

In some embodiments, an apparatus may include a deformation sensor, the deformation sensor being made of a deformable material, an electrode incorporated into the deformation sensor, an electrically conductive member being spaced apart from the first electrode at a distance and being incorporated into the deformation sensor; and a controller programmed to determine when the distance between the electrode and the electrically conductive member changes by measuring changes in capacitance between the electrode and the electrically conductive member.

The deformation sensor may include a hollow interior and the electrode and the electrically conductive member are positioned within the hollow interior.

At least one of the electrode and the electrically conductive member may include an electrically insulating coating.

The electrode may be electrically insulated from the electrically conductive member.

The electrically conductive member may be a second electrode.

The deformation sensor may include a floating coupler.

The apparatus may include a closure assembly. The closure assembly may include a first member having a first surface, a second member having a second surface. The second member may be movable to bring the first surface and the second surface into close proximity to each other and the deformation sensor may be disposed adjacent to at least one of the first surface and the second surface.

The first member may be a window frame and the second member is a window.

The first member may be a door frame and the second member is a door.

The first member may be a door frame and the second member is a sliding door.

The second member may be a sliding door.

The second member may be a revolving door.

The second member may be movable with a power assembly.

The controller may be programmed to move the second member away from the first member when a measured capacitance increases.

In some examples, an apparatus may include a first member of a closure assembly, a second member of the closure assembly movable with respect to the first member where movement of the second member is powered with a power assembly, a deformation sensor incorporating an electrode, and a controller programmed to measure a change in capacitance with the electrode. In some cases,

The command may be to move the second member away from the first member.

The command may be to stop movement of the second member.

The second member may be sliding member.

The second member may be rotary member.

The second member may be a hinged member.

In some examples, the deformation sensor may be a sealing member.

In some examples, the deformation sensor may include a gasket.

In some examples, the deformation sensor is an elongated member.

DETAILED DESCRIPTION OF THE INVENTION

Thus, various embodiments may omit, substitute, or add various procedures or components as appropriate. For instance, it should be appreciated that the methods may be performed in an order different than that described, and that various steps may be added, omitted, or combined. Also, aspects and elements described with respect to certain embodiments may be combined in various other embodiments. It should also be appreciated that the following systems, methods, devices, and software may individually or collectively be components of a larger system, wherein other procedures may take precedence over or otherwise modify their application.

For purposes of this disclosure, the term “aligned” generally refers to being parallel, substantially parallel, or forming an angle of less than 35.0 degrees. For purposes of this disclosure, the term “transverse” generally refers to perpendicular, substantially perpendicular, or forming an angle between 55.0 and 125.0 degrees. For purposes of this disclosure, the term “length” generally refers to the longest dimension of an object. For purposes of this disclosure, the term “width” generally refers to the dimension of an object from side to side and may refer to measuring across an object perpendicular to the object's length.

For purposes of this disclosure, the term “electrode” generally refers to a portion of an electrical conductor intended to be used to make a measurement, and the terms “route” and “trace” generally refer to portions of an electrical conductor that are not intended to make a measurement. For purposes of this disclosure in reference to circuits, the term “line” generally refers to the combination of an electrode and a “route” or “trace” portions of the electrical conductor. For purposes of this disclosure, the term “Tx” generally refers to a transmit line, and the term “Rx” generally refers to a sense line.

It should be understood that use of the terms “touch pad” and “touch sensor” throughout this document may be used interchangeably with “capacitive touch sensor,” “capacitive sensor,” “capacitive touch and proximity sensor,” “proximity sensor,” “touch and proximity sensor,” “touch panel,” “touchpad,” and “touch screen.”

It should also be understood that, as used herein, the terms “vertical,” “horizontal,” “lateral,” “upper,” “lower,” “left,” “right,” “inner,” “outer,” etc., can refer to relative directions or positions of features in the disclosed devices and/or assemblies shown in the Figures. For example, “upper” or “uppermost” can refer to a feature positioned closer to the top of a page than another feature. These terms, however, should be construed broadly to include devices and/or assemblies having other orientations, such as inverted or inclined orientations where top/bottom, over/under, above/below, up/down, and left/right can be interchanged depending on the orientation.

Capacitance touch systems may be built to detect changes in an electric field. Any change in the environment near the sensor may change the electric field. Capacitance touch systems may measure charge movement that may be correlated with a stimulus signal which may directly relate to the behavior of the electric field. Theses sensors may then monitor absolute measurements for changes, thus allowing the system to monitor for changes in the electric field. Given the proper frame of reference, the changes in charge movement can be used to track an object's arrival, departure, or position near the sensor.

Typically, a touch controller includes at least one of a central processing unit (CPU), a digital signal processor (DSP), an analog front end (AFE) including amplifiers, a peripheral interface controller (PIC), another type of microprocessor, and/or combinations thereof, and may be implemented as an integrated circuit, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a combination of logic gate circuitry, other types of digital or analog electrical design components, or combinations thereof, with appropriate circuitry, hardware, firmware, and/or software to choose from available modes of operation for the touch sensor (e.g., self-capacitive sensing, mutual capacitive sensing, or the like).

Typically, a touch controller also includes at least one multiplexing circuit to alternate which electrodes are operating as a drive electrode or a sense electrode. The driving electrodes can be driven one at a time in sequence, or randomly, or all at the same time in encoded patterns. Other configurations are possible such as self-capacitance mode where the electrodes are driven and sensed simultaneously. Other configurations are also possible.

FIG. 1is an end-view, cross-sectional schematic of a deformation sensor system100in accordance with disclosed embodiments. As shown, system100includes a flexible or otherwise deformable sensor10that comprises a flexible gasket12. Gasket12may comprise any suitable material for a given application. For example, if the deformation sensor system100is to be installed on a vehicle door, or the like, gasket12may comprise a rubber, or rubber-like material that compresses when the door is shut and additionally functions to seal the interface between the door and vehicle frame. Gasket12is shown inFIG. 1as having a generally circular cross-section, but other shapes are also possible as one of ordinary skill in the art having the benefit of this disclosure would understand.

As shown in this embodiment, gasket12houses a number of electrodes14(three electrodes14A-14C are shown inFIG. 1). While three electrodes14A-C are shown inFIG. 1that is merely exemplary and any suitable number of electrodes may be used as further disclosed herein. Likewise, electrodes14A-C are shown as being spaced generally equidistantly (i.e., distance AC=distance AB=distance BC), but that is exemplary and other configurations may be used.

As indicated schematically, electrodes14A-C are in communication with a touch controller circuit16which, as generally described above, controls the driving and sensing functions of the electrodes14A-C in order to create electric fields, and detect changes in capacitance, and the like. Among other things, touch controller circuit16can be “tuned” to accommodate any particular geometry, arrangement, and configuration of electrodes14. In other words, because the change in capacitance due to deformation is detected, the original configuration may not be critical other than to set a baseline capacitance value in the touch controller circuit16.

As also indicated schematically, touch controller circuit16communicates with a motion interface system18that interacts with the moving parts upon which the deformable sensor10is installed as outlined below. In embodiments where deformable sensor10is installed on a moving door, for exampleFIGS. 4-5, motion interface system18may comprise a motion interrupter, such as a locking hinge, a shaft, gearing, a reversible motor, or the like that, when a deformation of sensor10is detected, causes the motion of the door to be arrested, reversed, slowed, or the like. As a person of ordinary skill in the art having the benefit of this disclosure would understand, other motion interface systems18may also be used such as brakes, clutches, transmissions, or the like. Additionally, the motion interface systems18need not be mechanical, and electronic “kill switches” or the like may be used. Furthermore, in some embodiments, motion interface systems18need not arrest or change the motion of the moving part(s), but may trigger an alarm (visual, audible, vibratory, combinations thereof, or the like).

Additionally, embodiments of system100may be configured so that sensing of a deformation or object in proximity to gasket12(and electrodes14A-C) causes motion interface system18to move a portion of the system100(e.g., open a door, window, gate, or the like). For example, for embodiments of system100that are installed on a refrigerator a predetermined number of presses on, or a “swipe” along, gasket12may cause motion interface system18to open the refrigerator door.

FIG. 2is an end-view, cross-sectional schematic showing a deformation of sensor10of the system100as shown inFIG. 1in accordance with disclosed embodiments.FIG. 1shows the system100in an initial, undeformed state for deformable sensor10andFIG. 2shows the sensor10during a deformation of sensor10by an object20. As shown, flexible gasket12is deformed by the object20(which may be a finger, hand, or any other object). That deformation causes at least one of the electrodes14(inFIG. 2, electrode14C) to move and change the relative locations of the electrodes14A-C (i.e., distance AC distance BC) which also changes the sensed capacitance value of the electrodes14A-C by touch controller circuit16. As discussed above, touch controller circuit16may also communicate to motion interface system18upon sensing a change in capacitance that indicates the presence of an object20.

As one of ordinary skill in the art having the benefit of this disclosure would understand, embodiments of touch controller circuit16may be programmed or designed to differentiate between deformation or proximity sensing due to an object20and deformation or proximity sensing due to initial states of the system100. For example, for embodiments of system100installed on a vehicle door, deformation of gasket12due to the door being closed would be recognized by touch controller circuit16as a baseline closed state or the like.

FIG. 3is a schematic illustration of a segmented deformable sensor10in accordance with disclosed embodiments. As indicated inFIG. 3, embodiments of deformable sensor10may comprise discrete, or otherwise segmented electrodes14A-D that, among other things, may provide more precise information to touch controller circuit16regarding the location of an object (not shown inFIG. 3) that is deforming the sensor10. For example, if touch controller circuit16senses a change in capacitance from only electrode14B, then that information may be communicated to a motion interface system (not shown inFIG. 3) and only portions of the motion may be altered, or the like. Likewise, as discussed above, for embodiments installed on a vehicle door or the like, segmented electrodes14A-D may be used to indicate the presence of a finger or other object20in the path of proper door closure by a deformation or proximity sensing in a single segment or the like. Other uses for a segmented deformable sensor10and responses by a motion interface system18are also possible.

FIG. 4is a schematic partial illustration of a deformable sensor10installed on a vehicle door in accordance with disclosed embodiments. As indicated, flexible gasket12may be installed on an upper portion22of a vehicle door above a window24as is customary in many vehicle doors26. In the event a finger, hand, or other object (not shown inFIG. 4) gets pinched between the upper portion22of the door26and the vehicle frame (not shown inFIG. 4) the deformable sensor10may signal a change in capacitance that is sensed by touch controller circuit16and communicated to motion interface systems18(both not shown inFIG. 4) and arrest or otherwise alter the motion of the door26to prevent injury or the like.

Similarly, for embodiments where gasket12is installed around window24(e.g., to seal the closed window24against upper portion22of the door26) a predetermined number or pattern of touches on gasket12may cause the window to open, close, or otherwise move. Additionally, a normal closed (or open) state may be recognized by the touch controller16(not shown inFIG. 4) for either the window24or the door26and deviations from those normal states may trigger anti-theft systems (not shown) on the vehicle or the like.

FIG. 5is a schematic illustration of a deformable sensor10installed on an overhead door28in accordance with disclosed embodiments. As indicated inFIG. 5, an overhead door28(i.e., a garage door or the like) may include a flexible gasket12on the end of the door28that contacts the ground30. As disclosed herein, when a deformation of sensor10is sensed, the motion interface systems may arrest, open, or otherwise alter the motion of the door28.

FIG. 6is a schematic illustration of a deformable proximity sensor system600in accordance with disclosed embodiments. As discussed herein, in some embodiments, it may be desirable to detect an object20prior to deformation of sensor10, thus, sensor10may be configured to sense changes in capacitance due to the proximity of an object20. For example, sensor10may comprise a flexible, conducting material that functions as one of the system600electrodes120. Another of the system600electrodes140may be located within flexible electrode120. In some embodiments, sufficient electrodes are provided so that proximity sensing may be performed in addition to, or instead of, deformation sensing. As disclosed herein, bringing a finger or object20in proximity to the flexible electrode120may cause the system600to open, close, or otherwise alter the motion of one or more motive components (e.g., a door, window, or the like). Other configurations may also be used.

FIG. 7depicts an example of a deformation sensor700. In this example, the deformation sensor700includes a gasket material702that is deformable, a first electrode704disposed within a hollow interior706of the gasket material702, and a second electrode708disposed within the hollow interior706. In this example, the first and second electrodes704,708include an electrically insulating coating710on an exterior surface of the electrodes704,708. In the illustrated example, the electrically insulating coating710surrounds the electrodes704,708. But, in other configurations, the electrically insulating material may cover just a portion of an exterior of the electrodes704,708.

In some cases where the force on the deformation sensor700causes the first and second electrodes704,708to move toward each other, the electrically insulating coating710may prevent the first and second electrodes704,708from shorting out or otherwise forming an electrically conductive contact between each other. In some examples, the electrically insulating coating710may prevent the capacitance signals from being altered as though an electrically conducting contact was otherwise formed between the first and second electrodes704,708.

In the example ofFIG. 7, the deformation sensor700includes just two electrodes. In some examples where just two electrodes are used, the first electrode704may be a transmit electrode and the second electrode708may be a sense electrode. In this particular example, the transmit electrode704may carry a voltage, and the sense electrode may measure the capacitance between the two electrodes as the voltage is carried by the transmit electrode. When the distance between the two electrodes is different, the measured amount of capacitance between the electrodes may be different.

However, any appropriate number of electrodes may be used. For example,FIG. 8includes a first electrode800, a second electrode802, a third electrode804, and a fourth electrode806. In some examples, just one of the electrodes may be a transmit electrode and the other electrodes may be sense electrodes. However, in other examples, multiple transmit electrodes may be included.

In an alternative example, the deformation sensor808may include a first electrode800and a second electrode802. In some examples, the first electrode800may be a transmit electrode, and the second electrode802may be a sense electrode, or vice versa. The deformation sensor808may also include a floating coupler810. In some cases, the floating coupler may be an electrically conductive material that is not grounded. However, the distance between the electrodes800,802and the floating coupler810may affect the capacitance measurement. In some situations, as the deformation sensor808is compressed, the distance between the floating coupler810and the electrodes800,802may decrease causing a change in the capacitance measurement. In such a situation, the controller may determine that there has been a pinch or another type of deformation based on the change in capacitance.

FIG. 9Adepicts an example of a closure assembly900. In this example, the closure assembly900includes a sliding member902, a fixed member904, a deformation sensor906attached to a leading edge908of the sliding member902, and a power assembly910. In this example, the power assembly910can move the sliding member902towards or away from the fixed member904. While this example depicts the deformation sensor906attached to the sliding member902, in other examples, the deformation sensor906may be attached to the fixed member904.

The power assembly910may include a motor, a pump, a linear actuator, or another type of assembly that can apply power to cause the sliding member902to move. In some examples, the power assembly910may have the ability to cause the sliding member to move in two directions.

The power assembly910may also include a controller that receives signals from the deformation signal. In some examples, if the signal from the deformation sensor906indicates that the capacitance has increased, decreased, or otherwise changed when the sliding member902is moving towards the fixed member904, the controller may send a signal that causes the power assembly910to reverse the direction of the sliding member902, halt the movement of the sliding member902, slow down the movement of the sliding member902, disconnect the sliding member902from the power assembly902, or otherwise affect the movement, speed, power, or direction of the sliding member902.

The deformation sensor906may be deformed as a result of a person, hand, leg, another type of body part, a box, a cart, or another type of object being in the way of the sliding door902. In some examples when the deformation sensor906is on the leading edge908of the sliding member902, the deformation sensor906comes into contact with the body part of other type of object first, thereby generating a deformation signal from the deformation sensor906as deformation sensor906is being pinched.

In some cases, the controller is also aware of the position of the leading edge908of the sliding member902. The controller may receive input from other sensors that can determine the position of the leading edge908, such as cameras, radar, optical sensors, other types of sensors, and so forth. In some embodiments when the leading edge908of the sliding member902approaches the fixed member904, the deformation sensor906may create a seal between the sliding member902and the fixed member904. As the seal is being created, the electrodes in the deformation sensor906may change their relative position with each other causing a change in capacitance. In this type of example, the controller may determine that location of the deformation sensor906is at that position where the seal should be created and not send a signal to the power assembly910.

In some cases, the capacitance change that results from forming a seal is different from the capacitance change that results from a person's hand or other body part being pinched with the deformation sensor906. In this type of example, the controller may distinguish between forming a seal and pinching an object with the deformation sensor906.

In another example, as depicted inFIG. 9B, the deformation sensor906protrudes beyond the leading edge908of the sliding member902, and the fixed member904includes a recess1000that receives the deformation member906. In this example, the deformation member906may or may not contribute to forming a seal between the sliding member902and the fixed member904. In some cases in the illustrated example ofFIG. 9B, when the sliding member902and the fixed member904are together, the deformation sensor906may not be altered such that a change is capacitance is triggered.

FIG. 10depicts an example, where a closure assembly900includes a first sliding member1002powered with a first power assembly1004and a second sliding member1006powered by a second power assembly1007. A first deformation sensor1008may be attached to a first leading edge1010of the first sliding member1002, and a second deformation sensor1012may be attached to a second leading edge1014of the second sliding member1006. In this example, both sliding members1002,1006may detect when obstacles are encountered. In some examples, the first and second deformation sensors1008,1012may not be deformed when the first and second sliding members1002,1006come into contact with each other when no objects are pinched between the first and second sliding members1002,1006. In alternative examples, the seal created by the deformation sensors1008,1012may have a distinctive signal characteristic that is distinguishable from the signals that would otherwise result if an object were pinched between the first and second sliding members1002,1006.

In some examples when the deformation forms the seal, the seal is a light seal that may prevent a breeze or another type fluid from moving past the deformation sensor at a low force. In this type of example, the force pushing the deformation sensor into contact with another surface may be low enough that the electrodes in the deformation sensor are not significantly moved. On the other hand, when an object is pinched with the deformation sensor, at least one of the electrodes may move a relatively significant distance with respect to the other electrode causing a greater capacitance change.

In some examples, a controller in the first power assembly1004may send a signal to the controller in the second power assembly1007when the signal from the first deformation sensor1008indicates that an object has been encountered. Based on the signal from the first controller, the second sliding member1006may be caused to react to reverse its direction or otherwise respond as thought the signal had come from the second deformation sensor1012.

The closure members900depicted inFIGS. 9 and 10may be any appropriate type of closure member. For example, the closure members may be a power window, a motorized sliding door on a car, an automatic door into a building, a gate, incorporated into a fence, a garage door, another type of closure member, or combinations thereof.

FIGS. 11 and 12depict examples of closure assemblies1100involving a rotary member1102. In these examples, the closure assembly1100may include a revolving door. In this example, the rotary member1102may be located within a chamber1104partially defined by an enclosure1106. Panels1108may extend away from the rotary member1102towards the surface of the enclosure1106to temporarily provide an ingress and egress to the enclosure as the rotary member1102is rotating. In some cases, a small gap may be formed between the outer most edge1109of the panels1108and the surface of the enclosure1106as the panel moves through the enclosure1106. In other examples, no gap may exist.

In the example depicted inFIG. 11, a deformation sensor1110is attached to a fixed edge1112of the enclosure1106. As the outer most edge1109of the panel1108approaches the fixed edge1112of the enclosure1106, the outer most edge1109and the fixed edge1112may come together or closely together. In some examples, when there are no objects positioned to obstruct the movement of the panels1108, the outer most edge1109of the panel1108may pass by the deformation sensor1110without deforming the deformation sensor1110. In this type of example, a controller of a power assembly causing the rotary member1102to move may receive no signals from the deformation sensor1110that would result in altering the speed, power, force, or direction of the rotary member1102.

In a different scenario where an object such as a hand or other body part are pinched between the outer most edge1109of the panel1108and the fixed edge1112of the enclosure1106, the deformation sensor may be deformed, causing a change in the measured capacitance. The change of capacitance may result in the controller altering the speed, power, and/or the direction of the rotary member1102. For example, if an object is pinched, the controller may cause the rotary member to rotate in an opposite direction to free the object. In other examples, the controller may cause the rotary member to disengaged from the power assembly so that a user can manually move the panel1108to free the object.

In the example ofFIG. 12, the deformation sensor1110is located on the outer most edge1109of the panel1108. In some examples where there are no obstructions, the deformation sensor1110may move past the fixed edge1112without receiving push back by the fixed edge1112that would cause the deformation sensor1110to deform. However, in other scenarios where an object is being pinched between the panel1108and the fixed edge1112, the deformation sensor1110may be deformed triggering a command to alter how the power assembly is interacting with the rotary member1102.

FIG. 13depicts an example of a closure assembly1300incorporated into a vehicle1302. In this example, the deformation sensor1304may be located on a fixed surface1306where a moving edge1308of the sliding door1310may approach. In some examples, when the moving edge1308of the sliding door1310is secured, the moving edge1308may not apply a load on the deformation sensor1304that would cause the capacitance to significantly change. In some cases, the deformation sensor1304may help to form a seal between the fixed surface1306and the sliding door1310, but any capacitance changes caused by the formation of the seal may be distinguishable from capacitance changes resulting in a pinched object between the fixed surface1306and the sliding door1310. In other examples, the deformation sensor1304may be positioned on the sliding door1310.

FIG. 14also depicts an example of a closure assembly1300incorporated into a vehicle1302. In this example, the closure assembly1300includes a hinged door1400and the power assembly1402includes hydraulic actuators1404for moving the hinged door1400. In this example, the deformation sensor1304may be attached into an inside surface1408of the hinged door1400. However, in alternative examples, the deformations sensor1304may be placed on a fixed surface1406that forms a seal with the hinged door1400when the hinged door1400is closed.

FIG. 15depicts an example of a deformation sensor1304incorporated into a garage door1500. In this example, the deformation sensor1304is attached to a leading edge1502of the garage door1500. However, in other examples, the deformation sensor1304may be incorporated into the garage door at another location.

FIG. 16depicts an example of a method1600of using a deformation sensor. This method1600may be performed based on the description of the devices, module, and principles described in relation toFIGS. 1-15. In this example, the method1600includes measuring1602a change in capacitance between a first electrode and a second electrode when a deformation sensor is pinched.

FIG. 17depicts an example of a method1700of using a deformation sensor. This method1700may be performed based on the description of the devices, module, and principles described in relation toFIGS. 1-15. In this example, the method1700includes measuring1702a change in capacitance between a first electrode and a second electrode when a deformation sensor is pinched and sending1704a command to a power assembly when the deformation sensor is pinched. Method1700may optionally include reversing1706a direction of movement of the first closure member, the second closure member, or both response to receiving the command