Wheelchair with motor speed and torque control
A method varies motor torque inversely as a function of speed.
1 . A wheelchair motor control for varies motor torque inversely as a function of motor speed, wherein a torque adjustment is accomplished by making adjustments in the IR compensation of the motor control.
2 . A method of controlling a wheelchair that has a frame, wheels including driven wheels, motors connected to the driven wheels, a battery, and a control configured to apply power from the battery to the motors, the method comprising:
applying a voltage to the motors to drive the motors;
measuring the current drawn by the motors;
comparing the measured current with an expected current value;
modifying the voltage applied to the motors in response to a difference in the measured current and the expected current value, wherein the manner is which the voltage is modified is adjusted in relation to motor speed.
3 . The method of claim 2 in which the modification of the voltage includes increasing the voltage one rate of voltage increase when the speed of the wheelchair is high and at a second, higher rate of voltage increase when the speed of the wheelchair is low.
4 . The method of claim 2 in which the modification of the voltage includes an IR compensation that is adjustable in relation to a torque load on the motor.