Patent ID: 6661191
Filing Date: 2003-12-09
Classification: B62D

Abstract:
A vehicle steering control system of the type including an electric motor actuator, a motor driver circuit for generating and applying an electric current to the motor actuator, a current sensor for measuring the electric current from the motor driver circuit and generating a feedback current signal, said steering control system comprising:a steering wheel angle sensor for sensing a steering wheel angle and generating a steering wheel angle signal; a vehicle road wheel angle sensor for sensing a vehicle's road wheel angle and generating a vehicle road wheel angle signal; and a controller for setting an offset current signal and for processing the feedback current signal, the steering wheel angle signal, and the road wheel angle signal to generate a control signal for the motor driver circuit and the controller for comparing the control signal to a predetermined threshold value and subtracting the offset current signal from the electric current when the control signal is greater than the predetermined threshold value and the processor for comparing the control signal to a predetermined threshold value and setting the offset current signal equal to the initial offset value when the control signal is less than the predetermined threshold value.