A multi-tiered robust steering controller based on yaw rate and side slip estimation

In this paper we propose a multi-tiered full-size road vehicle steering controller that simultaneously considers kinematics and dynamics. The kinematic controller embeds a surface for converging to the desired path that is tuned based upon vehicle capability in order to provide robust yaw rate references commands. The dynamic controller then establishes a sliding surface for yaw rate error convergence that allows the controller to be tuned based upon vehicle speed. The dynamic controller is designed to be robust to lateral disturbances characterized by side-slip angle, which is estimated by a robust observer. Simulations verify capabilities of this system with various speeds and road friction coefficients. Experiments using a full scale road vehicle with lateral disturbances demonstrate this approach at low speeds.