Robust Yaw Damping of Cars with Front and Rear Wheel Steering

Abstract

For active car steering a robust decoupling control law by feedback of the yaw rate to front wheel steering was derived earlier. In the present paper this control law is extended by feedback of the yaw rate to rear wheel steering. A controller structure with one free damping parameter kD is derived with the following properties: i) Damping and natural frequency of yaw mode are independent of speedii) kD can be adjusted to the desired damping level iii) A variation of kD has no influence on the natural frequency of the yaw mode and no influence on the steering transfer function by which the driver keeps the car - considered as a mass point - on his planned path.