Apparatus and methods for control of a vehicle

Abstract

Method for controlling a vehicle that includes a support, at least one wheel, a platform coupled to the at least one wheel, a coupling structure having a support portion coupled to the support and a platform portion coupled to the platform that allows the support portion to move or slide fore and aft with respect to the platform portion, an actuator coupled to the coupling structure to control the position of the support portion relative to the platform portion, a drive coupled to the at least one wheel to deliver power to the at least one wheel to propel the vehicle and maintain the platform level, and a controller coupled to the drive to control the drive and coupled to the actuator to control the actuator.

1 . A vehicle comprising:
 a support;   at least one wheel;   a platform coupled to the at least one wheel;   a coupling structure having a support portion coupled to the support and a platform portion coupled to the platform that allows the support portion to move or slide fore and aft with respect to the platform portion;   an actuator coupled to the coupling structure to control the position of the support portion relative to the platform portion,   a drive coupled to the at least one wheel to deliver power to the at least one wheel to propel the vehicle and maintain the platform at a desired orientation; and   a controller coupled to the drive to control the drive and coupled to the actuator to control the actuator, wherein torque applied by the at least one wheel to an underlying surface vehicle is controlled by commanding the coupling structure to vary position of the support portion relative to the platform portion while maintaining the platform at the desired orientation.   
     
     
         2 . The vehicle of  claim 1 , wherein the controller is configured to command a specific position of the support portion relative to the platform portion to control the torque applied by the at least one wheel to the underlying surface to achieve a desired speed for the vehicle. 
     
     
         3 . The vehicle of  claim 1 , comprising an input device for receiving a vehicle speed command value from a user or controller and varying the position of the support portion relative to the platform portion to control the torque applied by the at least one wheel to the underlying surface to achieve the vehicle speed command value. 
     
     
         4 . The vehicle of  claim 1 , comprising a wheel speed sensor and a coupling structure speed sensor to provide signals to the controller to command the coupling structure to vary the position of the support portion relative to the platform portion to control the torque applied by the at least one wheel to the underlying surface to control the speed of the vehicle. 
     
     
         5 . The vehicle of  claim 1 , comprising a speed limiter module configured to command the controller to constrain the size of a speed command signal to constrain the torque applied by the at least one wheel to the underlying surface to constrain the speed of the vehicle over a period of time in response to varying the position of the support portion relative to the platform portion over the period of time. 
     
     
         6 . The vehicle of  claim 1 , wherein the coupling structure is a slide assembly, the support portion is a rail, and the platform portion is a rail guide. 
     
     
         7 . The vehicle of  claim 1 , wherein the coupling structure is a four bar linkage. 
     
     
         8 . A dynamically-balancing vehicle, the vehicle comprising:
 a support;   at least one wheel;   a platform coupled to the at least one wheel;   a coupling structure having a support portion coupled to the support and a platform portion coupled to the platform that allows the support portion to move or slide fore and aft with respect to the platform portion;   an actuator coupled to the coupling structure to control the position of the support portion relative to the platform portion,   a drive coupled to the at least one wheel to dynamically balance the vehicle and provide power to the at least one wheel to propel the vehicle; and   a controller coupled to the drive to control the drive and coupled to the actuator to control the actuator, wherein speed of the vehicle is controlled by commanding the coupling structure to control the position of the support portion relative to the platform portion based on present operating wheel torque for the vehicle and present wheel torque capability to maintain propulsion capability margins required for balancing the vehicle.   
     
     
         9 . The vehicle of  claim 8 , comprising a position sensor to determine actual position of the support portion relative to the platform portion, wherein the controller compares position commands to the actual position and outputs actuator commands based on the comparison. 
     
     
         10 . The vehicle of  claim 8 , comprising an effort limiter module coupled to the controller to enable the coupling structure to only command positions that maintain balance of the vehicle. 
     
     
         11 . The vehicle of  claim 10 , wherein the effort limiter is configured to only enable the coupling structure to command positions where the sum of the present operating wheel torque and the torque required for balancing the vehicle demands a motor current level which is below estimated available drive motor current of a power source used to power operation of the vehicle. 
     
     
         12 . The vehicle of  claim 8 , comprising a user input for commanding fore/aft speed, yaw rate, or both, of the vehicle and the controller is configured to control the speed of the vehicle based on the commanded, measured or estimated fore/aft torque, yaw torque, or both. 
     
     
         13 . The vehicle of  claim 8 , wherein the coupling structure is a slide assembly, the support portion is a rail, and the platform portion is a rail guide. 
     
     
         14 . The vehicle of  claim 8 , wherein the coupling structure is a four bar linkage. 
     
     
         15 . A dynamically-balancing vehicle, the vehicle comprising:
 a support;   at least one ground-contacting element;   a platform coupled to the at least one ground-contacting element;   a coupling structure having a support portion coupled to the support and a platform portion coupled to the platform that allows the support portion to move or slide fore and aft with respect to the platform portion;   an actuator coupled to the coupling structure to control the position of the support portion relative to the platform portion;   a drive coupled to the at least one ground-contacting element to dynamically balance the vehicle and provide power to the at least one ground-contacting element to propel the vehicle; and   a controller coupled to the drive to control the drive and coupled to the actuator to control the actuator, and wherein the controller balances the vehicle by determining position of the coupling structure support portion relative to the coupling structure platform portion and controlling position of the coupling structure support portion relative to the coupling structure platform portion to move position of the vehicle center of gravity while dynamically balancing the vehicle.   
     
     
         16 . The vehicle of  claim 15 , wherein the controller is configured to move the support portion relative to the platform portion to dynamically balance the vehicle while the vehicle is at a commanded rest position relative to an underlying surface and the support is at least substantially level. 
     
     
         17 . The vehicle of  claim 15 , wherein the controller is configured to vary position of the support portion relative to the platform portion in response to a change in the position of the vehicle center of gravity. 
     
     
         18 . The vehicle of  claim 15 , wherein the step of controlling position of the support portion relative to the platform portion is performed in response to vehicle fore/aft speed commands, yaw rate commands, or both, satisfying one or more predetermined conditions. 
     
     
         19 . The system of  claim 15 , wherein the step of controlling position of the support portion relative to the platform portion is performed when the vehicle is operating in a predetermined mode of operation. 
     
     
         20 . The system of  claim 15 , wherein the controller is configured to disable the step of controlling position during vehicle takeoff and landing modes. 
     
     
         21 . The system of  claim 20 , wherein the controller is configured to enable the step of controlling position after the vehicle enters a balancing mode from the takeoff mode. 
     
     
         22 . The vehicle of  claim 15 , wherein the coupling structure is a slide assembly, the support portion is a rail, and the platform portion is a rail guide. 
     
     
         23 . The vehicle of  claim 15 , wherein the coupling structure is a four bar linkage.