System and method of controlling a vehicle having yaw stability control

A method of controlling a vehicle having a steer-by-wire system with enhanced yaw stability during a yaw motion disturbance, the method comprising:

• sensing a steering wheel angle, lateral acceleration, speed, and a yaw rate of the vehicle;
• generating a desired yaw rate signal indicative of a desired yaw rate, the desired yaw rate being based on the steering wheel angle and the vehicle speed;
• generating a yaw error signal indicative of a yaw error, the yaw error being based on the desired yaw rate and the measured yaw rate;
• generating a compensating, steering angle signal of the steer-by-wire system implementing a gain scheduled proportional-integral control strategy and an instant proportional-integral control strategy the compensating steering angle signal being indicative of a compensating steering angle, if the yaw error is determined to be greater than an error threshold;
• generating an extra road wheel angle signal indicative of an extra road wheel angle to compensate for the yaw motion disturbance defining a time zero, if the yaw error is determined to be greater than an error threshold;
• generating a road wheel angle signal indicative of a road wheel angle, the road wheel angle being based on the extra road wheel angle and a steering wheel angle before a predetermined time lapse, the road wheel angle being based on the steering wheel angle after the predetermined time lapse relative to the time zero;
• and
• applying torque to the road wheels to move the road wheels consistent with the road wheel angle.

A system for controlling a vehicle having a steer-by-wire system with enhanced yaw stability during a yaw motion disturbance, the system comprising:

• a driver interface system for sensing a steering wheel angle of the vehicle;
• an electronic control unit configured to generate a road wheel angle signal to compensate for the yaw motion disturbance, the road wheel angle being based on an extra road wheel angle and a steering wheel angle before a predetermined time lapse, the road wheel angle being based on the steering wheel angle after the predetermined time lapse relative to the time zero;
• and
• a road wheel actuating system for sensing lateral acceleration, speed, and measured yaw rate of the vehicle and for applying torque to the road wheels to move the road wheels consistent with the road wheel angle based on the road wheel angle signal and the predetermined steering ratio.