The Path Tracking of Four-Wheel Steering Autonomous Vehicles via Sliding Mode Control

This paper researches the path tracking problem for four-wheel steering (4WS) autonomous vehicles (AVs). A 4WS dynamics model of error is established. An analysis of steady state error point that 4WS AVs can eliminate steady state error in ideal condition but traditional Front-Wheel steering (FWS) AVs cannot achieve. By introducing sideslip angle, two sliding mode controllers are utilized to converge lateral offset and heading error to zero and keep vehicle stability in extreme condition. A J-turn test and a single lane change test are conducted in CARSIM-Simulink simulation to confirm that the performance of 4WS AVs is superior to FWS AVs.