Intelligent Vehicle Path Tracking and Stability Control Method Based on Extension Coordinated Control of AFS and DYC

To enhance vehicle handling stability and address the limitations of active front steering (AFS) in maintaining stability when the tire lateral force becomes saturated, this paper designed A phase-plane-based extension coordinated control system by using direct yaw moment control (DYC). The vehicle driving state is divided based on the boundary of the β – γ. phase plane stable domain, corresponding to the classical domain, extension domain and non-domain in the extension set, and the correlation function is solved using the extension theory. The range of the vehicle domain and the control mode are determined by the value of the correlation function. When the vehicle is in the classical domain, the AFS control method alone is used to improve the path tracking accuracy. When the vehicle is in the extended domain, the AFS and DYC coordinated control method is adopted. When the vehicle is in the non-domain, DYC is used alone to improve stability. The coordination weights between controllers are determined by the correlation function. The simulation results show that the maximum tracking error under double lane change and lane changing conditions is reduced by 27.59% and 55.56%, respectively. Then the HIL tests verify the effectiveness of the proposed algorithm, which can significantly improve the trajectory tracking ability and handling stability of the vehicle.