Abstract:
A collision damage prevention system is disclosed which may be installed on many standard powered mobility vehicles for handicapped persons. The system includes an array of one or more sensors placed around the periphery of the powered mobility vehicle, a switch for each sensor, and a central control module which receives input from the switches, turns the vehicle off and/or applies braking power to prevent damage from a collision. The system then prompts the operator to acknowledge the collision and guides the operator into the appropriate direction to move the vehicle&#39;s controls in order to move away from the object collided with.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    Reference is hereby made to provisional application No. 60/466,320, filed on Apr. 29, 2003, from which priority is hereby claimed pursuant to 35 U.S.C. § 120. 
     
    
     
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH  
         [0002]    Not Applicable.  
         REFERENCE TO “MICROFICHE APPENDIX” 
         [0003]    Not Applicable.  
         BACKGROUND OF THE INVENTION  
         [0004]    This Invention relates to a device and method for preventing damage from collisions occurring during the operation of a powered wheelchair or similar mobility device. Powered wheelchairs and similar powered mobility devices are self-powered vehicles which are commonly used by handicapped individuals to give them mobility, most particularly within the confines of the individual&#39;s home or within businesses the individual visits. These vehicles have greatly enhanced the lives of those affected by disease, stroke, injury, or the ravages of aging; however, the typical user is often restricted in head movement, visual and auditory acuity, and other sensory perception (including vibration) such that it becomes impossible for the typical user to adequately observe the boundaries of the vehicle as the user maneuvers among furniture, around comers, and through doors of the home or business. It is very common for these vehicles to cause severe damage to their surroundings, even when maneuvered at very low speeds, because of the great power capabilities of these vehicles necessary to overcome slopes, door thresholds, and other obstacles in normal use. It is especially common for a person with hearing difficulties, upon colliding with a door frame or piece of furniture, to continue to apply power in the same direction, rather than to ease the mobility device away from the object. The result is that severe damage often results from these collisions, both to the object collided with as well as the vehicle, with deep scratches, gouges, and holes left in the former, or bent operating handles and other damage done to the latter. Problems are not limited to those with hearing difficulties, however; even for those who realize that a collision has occurred, the controls of common mobility devices are often counterintuitive regarding the direction the user needs to move to avoid damage. A need therefore exists for a system which will detect an impending collision between a handicapped mobility device and an object which will stop the mobility device from causing damage to the object, alert the user to the impending collision, and guide the user towards making appropriate course modifications to prevent damage to the mobility device and the object.  
           [0005]    The present Invention is therefore directed remedying these problems by providing a device and method for modifying an existing powered mobility device which, when installed on such a powered mobility device, will detect an impending collision, will prevent damage to the object collided with and will alert the user by stopping the vehicle and/or sounding an alarm, and will give the user guidance on the appropriate corrective action to take before the object is damaged.  
         SUMMARY OF THE DISCLOSURE  
         [0006]    In accordance with the present Invention, a peripheral sensor system having a tape switch or bumper switch or similar device is attached to the outer periphery of the powered mobility device. The peripheral sensor system includes the tape switch, bumper switch, or similar switch as described, which is mounted to a sensor support framework, plus an electronic control module which interfaces with the power control of the powered mobility device on which the Invention is installed. The sensor support framework consists essentially of a bumper mounted to the vehicle by means of existing bolts and is made from spring steel or other resilient, damage resistant material. The electronic control module further includes a reset timer and an output panel with a series of light-emitting diodes or similar lighting devices. Upon contact with an object, the tape switch or bumper switch closes, energizing the electronic control module which then shuts down the vehicle, displays a light to alert the user that a collision has occurred, further displays a light to alert the user as to what corrective action needs to be taken to prevent damage, and starts the reset timer, which will automatically reset the system after a predetermined delay period.  
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0007]    [0007]FIG. 1 shows a typical powered mobility vehicle in oblique view.  
         [0008]    [0008]FIG. 2 shows a top view of a typical powered mobility vehicle.  
         [0009]    [0009]FIG. 3 shows a top view of a typical mobility vehicle with the collision damage prevention system installed.  
         [0010]    [0010]FIG. 4 shows a rear view of a typical mobility vehicle with the collision damage prevention system installed.  
         [0011]    [0011]FIG. 5 shows a left side view of a typical mobility vehicle with the collision damage prevention system installed.  
         [0012]    [0012]FIG. 6 shows a conceptualization of the connections between major components of the collision damage prevention system.  
         [0013]    [0013]FIG. 7 shows a detailed cross-sectional view of the pneumatic sensors and sensor switches.  
         [0014]    [0014]FIG. 8 shows the preferred input/output user interface.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0015]    [0015]FIGS. 1 and 2 show a typical powered mobility vehicle  10 . Such a vehicle has a seat  20 , footrest  22 , and armrests  24  to accommodate the user. Mounted to one of the armrests  24  is a steering control module  30  with which the user operates the vehicle. The seat  20  and footrest  22  are mounted to the body  50 , which houses the unit&#39;s battery and motor. The vehicle additionally has a plurality of wheels, typically a pair of main drive wheels  40 , a pair of rear steering wheels  42 , and a set of forward wheels  44 . The latter may or may not be utilized in steering the vehicle during its operation.  
         [0016]    [0016]FIGS. 3, 4, and  5  disclose a typical powered mobility vehicle  10  with the collision damage prevention system  100  installed. Around the periphery of the vehicle  10 , a sensor support framework  202  (made of spring steel or similar resilient, semiflexible material that is damage resistant) is mounted, to which a plurality of sensors  200  (preferably six) are installed. It will be understood that due to the nature of the modular design of the sensors  200 , the number of sensors can be varied from as few as one to as many as needed. These sensors  200  may be tape or ribbon switches (which will be understood by those with ordinary skill in the art), but preferably comprise a pneumatic sensor and switch system described in further detail, infra. Referring to FIGS. 6, 7, and  8 , each of the sensors  200  is connected to a central control module  300 , which is interfaced with the powered mobility vehicle&#39;s user steering control module  30 . The central control module  300  includes electronic circuitry  310  for monitoring the status of the various sensors  200 . Those of ordinary skill in the art will understand how to build the necessary circuitry to accomplish the tasks needed. The central control module  300  also includes a user input/output interface  320  for communicating with the user of the powered mobility vehicle  10 . This user input/output interface  320  includes an on/off switch  322 , which is backlit by an on/off switch light-emitting diode (LED)  324 ; a reset switch  326 , which is similarly backlit by a reset switch LED  328 ; a collision alarm LED  330 ; and a plurality of directional instruction LED&#39;s  332 . The face of the input/output interface  320  further includes a number of preprinted instructions, particularly including preprinted instructions on the direction to move the steering apparatus of the powered mobility vehicle  10  to correct for a collision. The directional instruction LED&#39;s  332  are arranged on the face of the input/output interface  320  around the periphery of a silhouette of the powered mobility vehicle  10  such that one directional instruction LED  332  is associated with a particular sensor  200 ; for example, in a system with a sensor on the left front of the vehicle  10 , a directional instruction LED  332  is included in the input/output interface  320 . The on/off switch  322  may be used to turn the collision damage prevention system  100  on and off independently from the powered mobility vehicle  10 . This is a safety feature that allows a user to override the system in the event of an emergency requiring a user to evacuate a building. When the system is on, the on/off switch LED  324  is also on, indicating to the user that there is power to the collision damage prevention system  100 .  
         [0017]    The preferred sensor in this arrangement is a pneumatic sensor, both due to cost and ease of use considerations. Referring particularly to FIG. 7, a pneumatic sensor  400  consists of a formed rubber bumper  410  made from two superposed layers of rubber sealed at the edge by a sensor end cap  412 , which also serves to protect the edge of the rubber bumper  410 . The two layers of the pneumatic sensor  400  define a pneumatic cavity  418 . This assembly is mounted to the sensor support framework  202  by means of one or more set screws  414  and a hollow set screw  416 . The hollow set screw  416  is simply a screw with a hole passing through the long axis of the screw, causing the two ends of the screw to be in fluid communication. The hollow set screw  416  passes through one layer of the rubber bumper  410 . By this arrangement, the pneumatic cavity  418  is in fluid communication with a connecting tubing  430 , which is connected at one end to the hollow set screw  416  an at the other end to a pneumatic switch  420 . The pneumatic switch  420  includes a switch body  422 , a switch diaphragm  424 , a switch actuator plate  426 , and a capillary tube  432 .  
         [0018]    In operation, when the rubber bumper  410  contacts an object, the deformation of the bumper causes an increase in the air pressure within the bumper. This pressure is communicated through the hollow set screw  416  and connecting tubing  430  to the switch diaphragm  424 , depressing the diaphragm. As the diaphragm  424  is depressed, it operates upon the switch actuator plate  426 , thus tripping the switch  420  and closing the circuit, which thus alerts the central control module  300  that a collision has occurred. The capillary tube  432  provides a route for a controlled release or leakage of air pressure from within the pneumatic sensor  400 , thereby allowing the system to self-compensate for gradual variations in air pressure due to a variety of non-collision circumstances, including heating of the pneumatic sensor  400  (either due to exposure to sunlight or simply due to external temperature variations) as well as changes in the external barometric pressure.  
         [0019]    After a collision has occurred, thereby operating the pneumatic sensor  400  and pneumatic switch  420 , the central control module  300  receives input from the pneumatic switch  420 . The central control module  300  then automatically switches the powered mobility vehicle  10 &#39;s power off and/or applies the vehicle&#39;s brakes to prevent collision damage from occurring. At the same time, the control module input/output interface displays a number of things: first, the reset switch LED  328  is lighted intermittently, causing it to blink on and off, and second, the directional instruction LED  332  corresponding to the sensor registering a collision is also intermittently lighted, causing it to blink on and off, thereby signifying that there is contact between the corresponding sensor and an object. The user must then press the reset switch  326  in order to restore power to the powered mobility vehicle  10 . Upon activating the reset switch  326 , the reset switch LED  328  is turned off, power to the vehicle  10  is restored, and the unprotected ready-to-move LED  330  is lit, indicating to the user that the vehicle is ready to move with the shutdown system deactivated and that corrective action is needed as indicated by the appropriate directional information LED  332 . Furthermore, upon activation of the reset switch  326 , the central control module  300  starts an internal, adjustable timer which provides a delay period for the user to take corrective action as indicated by the input/output interface  320 . At the end of the delay period, the system automatically resets itself, and the ready-to-move LED  330  and the directional information LED  332  both turn off.  
         [0020]    It will be understood that the system  100  is intended to be mounted to a powered mobility vehicle  10  through the use of existing bolts as much as possible in order to minimize, and preferably to eliminate, any modifications to the vehicle  10 . This is desirable so as to avoid voiding any warranties. Ideally, the only modification necessary is the addition of an electrical interface to the standard user steering control module  30  to power the central control module  300 . It will be further readily apparent that the particular input/output interface  320  as described, with the automatic reset timer, are designed to avoid operator confusion or frustration which would cause the operator to disable the system.  
         [0021]    Those familiar with the art will understand the components of the invention, their methods of manufacture, and the methods of connecting them to form the complete Invention. While the preferred embodiment has been described, it will furthermore be understood that various changes can be made therein without departing from the spirit and scope of the invention.  
       CATALOGUE OF ELEMENTS  
       [0022]    [0022] 10  Powered mobility vehicle  
         [0023]    [0023] 20  Seat  
         [0024]    [0024] 22  Footrest  
         [0025]    [0025] 24  Armrests  
         [0026]    [0026] 30  User steering control module  
         [0027]    [0027] 40  Main power wheels  
         [0028]    [0028] 42  Rear steering wheels  
         [0029]    [0029] 44  Forward wheels  
         [0030]    [0030] 50  Body with motor  
         [0031]    [0031] 100  Collision damage prevention system  
         [0032]    [0032] 200  Sensors  
         [0033]    [0033] 202  Sensor support framework  
         [0034]    [0034] 300  Central control module  
         [0035]    [0035] 310  Control module circuitry  
         [0036]    [0036] 312  Control module circuit board  
         [0037]    [0037] 320  Control module input/output interface  
         [0038]    [0038] 322  System on/off switch  
         [0039]    [0039] 324  System on/off LED  
         [0040]    [0040] 326  Reset switch  
         [0041]    [0041] 328  Reset LED  
         [0042]    [0042] 330  Ready-to-move LED  
         [0043]    [0043] 332  Directional instruction LED  
         [0044]    [0044] 400  Pneumatic sensor  
         [0045]    [0045] 410  Rubber bumper  
         [0046]    [0046] 412  Bumper end cap  
         [0047]    [0047] 414  Set screw  
         [0048]    [0048] 416  Hollow set screw  
         [0049]    [0049] 418  Pneumatic cavity  
         [0050]    [0050] 420  Pneumatic switch  
         [0051]    [0051] 422  Switch body  
         [0052]    [0052] 424  Switch diaphragm  
         [0053]    [0053] 426  Switch actuator plate  
         [0054]    [0054] 430  Connecting tubing  
         [0055]    [0055] 432  Capillary tubing