Optimal vehicle stability control design based on preview game theory concept

In this paper, vehicle stability is represented by a cooperative dynamic game such that its two agents (players), namely, the driver and the direct yaw controller (DYC), are working together to provide more stability to the vehicle system. While the driver provides the steering wheel control, the DYC control algorithm is obtained by the well-known Nash game theory to ensure optimal performance as well as robustness to disturbances. The common bicycle model is put into discrete form to develop the game equations of motion. To evaluate the control algorithm developed, a nonlinear vehicle model along with the combined-slip Pacejka tire model is used. The control algorithm is evaluated for a lane change maneuver, and the optimal set of steering angle and corrective yaw moment is calculated and fed to the test vehicle. The simulation results show that the optimal preview control algorithm can significantly reduce lateral velocity and yaw rate which all contribute to enhancing vehicle stability.