초록 ▼

A turning control system for an electric vehicle includes a differential filter which receives a signal indicative of a desired vehicle steer angle and generates a pair of signals representative of proportional speed and direction at a left and a right drive wheel of the vehicle. Speed limit factors

A turning control system for an electric vehicle includes a differential filter which receives a signal indicative of a desired vehicle steer angle and generates a pair of signals representative of proportional speed and direction at a left and a right drive wheel of the vehicle. Speed limit factors generated by an angular speed limit filter and an operator set throttle control are applied to the signals indicative of proportional speeds to generate desired proportional speed signals. The desired proportional speed signals are applied to a motor coupling controller along with signals indicating the actual motor speeds. Error signals representative of the difference between the desired speed and the actual speed of each motor are scaled and integrated to generate lag signals (representative of accumulated error) and the lag signal of one motor is applied to the desired proportional speed signal of the other motor to generate coupled control signals which are applied to respective left and right motor control circuits.

대표청구항 ▼

A turning control system for an electric vehicle which traverses a support surface along a direction of travel, the vehicle having a left traction motor and a right traction motor, a left motor drive control circuit for controlling the operation of the left traction motor and a right motor drive con

A turning control system for an electric vehicle which traverses a support surface along a direction of travel, the vehicle having a left traction motor and a right traction motor, a left motor drive control circuit for controlling the operation of the left traction motor and a right motor drive control circuit for controlling the operation of the right traction motor, means drivingly coupling each traction motor with traction means for engaging and propelling the vehicle over a support surface, the traction means being laterally spaced from one another relative to the direction of travel of the vehicle, the turning control system comprising means for generating a signal representative of a desired vehicle steer angle, means receiving the desired vehicle steer angle signal and in response thereto, generating a left reference signal and a right reference signal, each reference signal being representative of the required speed and direction of the respective left and right traction motor for effecting a vehicle turn at the desired steer angle, the turning control system further including motor coupling means, the motor coupling means including means for receiving a signal representative of the instantaneous speed of the left traction motor, for receiving a signal representative of the instantaneous speed of the right traction motor and for receiving the reference signals and in response thereto, generating a signal representative of speed lag of the left traction motor and generating a signal representative of speed lag of the right traction motor, means for modifying the left reference signal as a function of the signal representative of the speed lag of the right traction motor to generate a left motor coupled control signal and means for modifying the right reference signal as a function of the signal representative of the speed lag of the left traction motor to generate a right motor coupled control signal, the turning control system further including means for applying the left motor coupled control signal to the left motor drive control circuit and means for applying the right motor coupled control signal to the right motor drive control circuit, whereby effective speed control is provided for each traction motor which compensates for speed lag in the respective opposite motor to avoid oversteering and understeering and to provide slip free engagement between the traction means and the support surface.