Adaptive longitudinal velocity and lane keeping control of four-wheel-steering vehicles

In this paper, a new adaptive longitudinal velocity and lane keeping control scheme for four-wheel-steering vehicles without measurement of lateral velocity is proposed. At first, a method to design ideal longitudinal velocities and ideal transient trajectories for relative lateral distance and relative yaw angle is shown. Then, an adaptive controller is developed so that the tracking error between actual vehicle and ideal trajectories become asymptotically stable. The developed controller doesn't require the measurement of lateral velocity of vehicles and the accurate knowledge of all vehicle parameters.