Variable Structure Model Reference Adaptive Control for autonomous steering of vehicle

This paper describes a Variable Structure Model Reference Adaptive Control (VS - MRAC) for active steering assistance of a two wheel steering vehicle. Its main goal is to avoid lane departures. The controller steers an equipped vehicle along a specially marked lane without cross-over lane markings. The stability of the system is checked by lyapunov theory. First, the vehicle dynamics for typical lateral maneuvers are described by Newton's formulation. Next, we are used torsional damper in model reference for comeback of vehicle to reference marked lane when the vehicle departure from reference marked lane. The proposed system can treat the nonlinear relationships between the side slip angles and lateral forces on tire, and the uncertainties on friction of the road surface, whose compensation are very important under critical situations. Finally, simulation results show that controller performance is stable and has robust capability on meandering roads.