Control of a personal transporter based on user position
An apparatus controller for prompting a rider to be positioned on a vehicle in such a manner as to reduce lateral instability due to lateral acceleration of the vehicle. The apparatus has an input for receiving specification from the rider of a desired direction of travel, and indicating means for reflecting to the rider a propitious instantaneous body orientation to enhance stability in the face of lateral acceleration. The indicating may include a handlebar that is pivotable with respect to the vehicle and that is driven in response to vehicle turning.
1. A transporter comprising:
a ground contacting module including a platform, two wheels, and a motorized drive imparting torque to the two wheels, the ground contacting module being unstable with respect to tipping in a fore-aft plane of the transporter;
a plurality of sensors;
a control shaft pivotally coupled to the ground contacting module at a pivot, the control shaft generating a yaw input signal, the yaw input signal based at least in part upon an orientation of the control shaft; and
a controller computing an amount of torque to maintain balance of the transporter, the controller modifying the yaw input signal based on a velocity of the transporter, the amount of torque based at least in part upon the modified yaw input signal and a pitch of the transporter sensed by at least one of the plurality of sensors;
wherein the motorized drive arrangement supplies the amount of torque to the two wheels.
2. The transporter of claim 1 , wherein the orientation comprises a pivotal orientation with respect to an axis of the pivot.
3. The transporter of claim 1 , wherein the controller modifies the yaw input signal as the velocity of the transporter increases.
4. The transporter of claim 1 , wherein the controller dampens the yaw input signal as the velocity of the transporter increases.
5. The transporter of claim 1 , wherein the controller modifies the yaw input signal in proportion to a square of the velocity of the transporter.
6. The transporter of claim 1 , wherein the controller modifies the yaw input signal based on a nonlinear relationship between the yaw input signal and the velocity of the transporter.
7. The transporter of claim 1 , wherein the controller modifies the yaw input signal based on a ramp function when the transporter is traveling in reverse.
8. The transporter of claim 1 , wherein the controller modifies the yaw input signal to reverse the direction of turning specified by the yaw input signal when the transporter is traveling in reverse.
9. The transporter of claim 1 , wherein the controller low pass filters the yaw input signal.
10. The transporter of claim 1 , wherein the controller modifies the yaw input signal based on data from one or more of the plurality of sensors.
11. A method for controlling a transporter, the transporter including a ground contacting module having a platform, two wheels, a motorized drive for imparting torque to the two wheels, a plurality of sensors, a controller, and a control shaft pivotally coupled to the ground contacting module at a pivot, the ground contacting module unstable with respect to tipping in a fore-aft plane of the transporter, the method comprising:
generating a yaw input signal based at least in part on the orientation of the control shaft;
modifying, by the controller, the yaw input signal to a modified yaw input signal based on a velocity of the transporter;
computing an amount of torque to maintain balance of the transporter, the amount of torque based at least in part upon the modified yaw input signal and a pitch sensed by at least one of the plurality of sensors; and
supplying, by the motorized drive arrangement, the amount of torque to the two wheels.
12. The method of claim 11 , wherein the orientation comprises a pivotal orientation with respect to an axis of the pivot.
13. The method of claim 11 , wherein modifying the yaw input signal comprises modifying the yaw input signal as the velocity of the transporter increases.
14. The method of claim 11 , wherein modifying the yaw input signal comprises dampening the yaw input signal as the velocity of the transporter increases.
15. The method of claim 11 , wherein modifying the yaw input signal comprises modifying the yaw input signal in proportion to a square of the velocity of the transporter.
16. The method of claim 11 , wherein modifying the yaw input signal comprises modifying the yaw input signal based on a nonlinear relationship between the yaw input signal and the velocity of the transporter.
17. The method of claim 11 , wherein modifying the yaw input signal comprises applying a ramp function to the yaw input signal when the transporter is traveling in reverse.
18. The method of claim 11 , wherein modifying the yaw input signal comprises reversing the direction of turning specified by the yaw input signal when the transporter is traveling in reverse.
19. The method of claim 11 , further comprising:
low pass filtering, by the controller, the yaw input signal.
20. The method of claim 11 , further comprising:
modifying, by the controller, the yaw input signal based on data from one or more of the plurality of sensors.