Path Tracking Control for Connected Automated Vehicle Using Lateral Stability Envelope at Handling Limits

To improve the lateral stability and accuracy of path tracking control for connected automated vehicle (CAV) at handling limit conditions, the paper develops a model predictive control (MPC) method ultizing a lateral stability envelope. Specifically, the lateral stability envelope for vehicle state variables (i.e., sideslip angle and yaw rate) is derived by analyzing dynamic changes in the limit slip angle of the front wheel. This envelope varies with the steering angle and is incorporated into the proposed MPC controller as a constraint, which can guarantee lateral stability at handling limits. To further enhance the tracking accuracy, a reference for the yaw rate is derived by backstepping control considering the lateral displacement error. This reference is formulated as the objective for the MPC controller to regulate tracking errors. Simulation experiments demonstrate that the proposed controller can decrease the yaw rate and steering angle fluctuations in path tracking with low road adhesion compared with the nominal controller.