Lane changing control of four wheels steering vehiclein intelligent transportation system

To improve the control performance for lateral motion of vehicle in automatic highway systems,the problem of lane changing of intelligent vehicle was studied by using four-wheel-steering technology.Assuming that the lateral acceleration of vehicle in a lane changing transition satisfied positive and negative trapezoid constraints,the reference yaw angle and yaw rate for lane changing were generated based on the predetermined virtual trajectory.Assuming that the information on yaw rate of vehicle could be measured with on-board sensors,the yaw-rate tracking control law for lane changing was designed by applying terminal sliding mode technology based on the lateral dynamic model of four-wheel-steering vehicle.Based on Lyapunov function method,the convergence property of the control system was obtained.Expected tracking performance is verified by the simulation,and the system tracking precision can be improved by using four-wheel-steering technology.