Fixed-time nonsingular based sliding mode lateral control for autonomous vehicle

Abstract

This paper presents a fixed-time nonsingular sliding mode control (FTNSMC) for lateral path tracking under external disturbances. Using a quintic equation to define the desired trajectory, the proposed control ensures that the tracking error converges to zero within a fixed and predefined time, regardless of the initial conditions, and achieves this without chattering. The Teaching-Learning-Based Optimization (TLBO) algorithm is employed to tune the control gains, enhancing the overall performance of the controller. System stability is rigorously proven using the Lyapunov approach. Two distinct initial positions, y1|t=0 = 0.3 and y2|t=0 = 0.4, were selected, and in both cases, the system achieved convergence within the same fixed time, T=1.51s, which is significantly lower than the calculated maximum allowable time, Tmax≈ 9.5s, thereby demonstrating the robustness and effectiveness of the proposed method.