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 laterally disposed wheels, a motorized drive arrangement imparting a torque to each of the two laterally disposed wheels, and a pivot, the ground contacting module being unstable with respect to tipping when the motorized drive arrangement is unpowered;
a steering input including a shaft having a handlebar grip, the shaft mounted to the pivot and displaceable about a first axis defined by the pivot;
a plurality of sensors, at least one of the plurality of sensors comprising a pitch sensor sensing a pitch of at least a portion of the transporter about a second axis, at least one of the plurality of sensors comprising a steering input sensor sensing an orientation of the shaft about the first axis; and
a controller determining the torque to be applied to the two laterally disposed wheels to maintain balance of the transporter while propelling the transporter in a desired direction at a desired speed, the desired direction specified at least in part by the orientation and the desired speed specified at least in part by the pitch, the controller directing the motorized drive arrangement to apply the torque.
2. The transporter of claim 1 , wherein the first axis lies in a plane transverse to the second axis.
3. The transporter of claim 1 , wherein the second axis comprises an axis of rotation of the two laterally disposed wheels.
4. The transporter of claim 1 , wherein the steering input sensor senses lateral displacement of the shaft.
5. The transporter of claim 1 , wherein the steering input sensor senses pivotal displacement of the shaft.
6. The transporter of claim 1 , wherein the shaft is biased to a position by at least one bias member.
7. The transporter of claim 6 , wherein the shaft is biased to a pre-selected position by the at least one bias member.
8. The transporter of claim 1 , wherein the displacement of the shaft is constrained to a plane, the plane being substantially transverse to a fore/aft plane of the transporter.
9. The transporter of claim 1 , wherein the plurality of sensors comprises at least one load sensor, the load sensor sensing a load on the platform.
10. The transporter of claim 9 , wherein the controller modifies application of the torque to the motorized drive arrangement based on the orientation if the sensed load is partially on the platform.
11. The transporter of claim 1 , wherein the plurality of sensors comprises a roll sensor sensing roll of the transporter, and wherein the controller determines the desired direction based at least in part on the sensed roll and the orientation.
12. A method for controlling a transporter, the transporter including a ground contacting module, a steering input shaft, a plurality of sensors, and a controller, the ground contacting module having a platform, two laterally disposed wheels, a motorized drive arrangement, and a pivot, the ground contacting module being unstable with respect to tipping when the motorized drive arrangement is unpowered, the steering input shaft including a shaft, the shaft mounted to the pivot and displaceable about a first axis defined by the pivot, at least one of the plurality of sensors including a pitch sensor, at least another one of the plurality of sensors including a steering input sensor, the method comprising:
sensing, by the pitch sensor, a pitch of at least a portion of the transporter about a second axis;
sensing, by the steering input sensor, an orientation of the shaft about the first axis;
computing, by the controller, a desired direction based on the orientation;
computing, by the controller, a desired speed based on the pitch;
determining, by the controller, a torque to be applied to the two laterally disposed wheels to maintain balance in the desired direction and at the desired speed; and
directing, by the controller, the motorized drive arrangement to impart the torque to each of the two laterally disposed wheels.
13. The method of claim 12 , wherein the first axis lies in a plane transverse to the second axis.
14. The method of claim 12 , wherein the second axis comprises an axis of rotation of the two laterally disposed wheels.
15. The method of claim 12 , further comprising:
sensing, by the steering input sensor, pivotal displacement of the shaft.
16. The method of claim 12 , further comprising:
biasing the shaft to a position by at least one bias member.
17. The method of claim 12 , further comprising:
constraining the orientation to a plane, the plane being substantially transverse to a fore/aft plane of the transporter.
18. The method of claim 12 , further comprising:
sensing, by at least one load sensor, a load on the platform, the at least one load sensor being at least one of the plurality of sensors.
19. The method of claim 18 , further comprising:
modifying, by the controller, application of the torque to the motorized drive arrangement based on the orientation if the sensed load is partially on the platform.
20. The method of claim 12 , further comprising:
sensing, by a roll sensor, roll of the transporter, the roll sensor being one of the plurality of sensors; and
determining, by the controller, the desired direction based at least in part on the sensed roll and the orientation.