Vehicle Stability Enhancement Using Sliding Mode Based Active Front Steering and Direct Yaw Moment Control

In this paper, active front steering and direct yaw moment of a vehicle are controlled simultaneously to improve its stability. The control strategy uses two structures, the upper and lower levels of control. The sliding-mode control (SMC) methodology is used in the upper-level control in order to generate the corrective steering wheel angle and yaw moment. The yaw moment is realized through braking between appropriate wheels in the second-level control. Stability of the sliding mode controller is proved using Lyapunov criterion. Yaw-rate and side-slip tracking performances of a non-linear vehicle model is simulated to show the proposed controller's effectiveness.