FEEDBACK-CONTROL OF 4-WHEEL STEERING USING TIME-DELAY CONTROL

In this paper, a new feedback controlled four-wheel steering (4WS) is proposed using a time delay control scheme which is suitable for the c ontrol of nonlinear systems. The proposed 4WS needs to sense the yaw v elocity and its time derivative to estimate the disturbance and the ve hicle parameter changes in the yaw dynamics. The control scheme is bas ed on the yaw reference model following control. The selection of the yaw reference model is discussed through the stability analysis of the linear model not to make the total system unstable. The numerical sim ulation is performed by DADS(R), a multibody simulation software packa ge, with a 16 degrees of freedom full car model. The results show that the proposed 4WS has a robust yaw damping to the steering input and a robust yaw rate gain against external disturbance.