Vehicle lane-keeping control under state time-delay and mismatched uncertain perturbations

To deal with the mismatched uncertainty and state time-delay perturbations in vehicle lane-keeping control, we propose a self-turning sliding mode control method. By using the linear matrix inequality theory, we develop the sufficient conditions for the existence of the sliding-mode, in which the system in the sliding phase is completely independent to the existing mismatched uncertainties and the state time-delay. The sigmoid function is adopted to replace the sign function in designing the self-tuning law, by which the boundary layer of the sigmoid function as well as the switching gain can be adjusted automatically to reduce the high frequency chattering in outputs. The stability of the control method is proved based on Lyapunov theorem. Simulation results show the correctness and feasibility of the proposed method.