Adaptive Model-Following Control of Four-Wheel Steering Vehicle

The optimal steering control laws of rear wheels for three axle vehicle on complex typical path are studied based on the certain vehicle model of closed loop control. The steering responses of vehicle are improved through using steering of state feedback. The actual vehicle model is considered as uncertain system. The cornering stiffness of front and rear wheels and outer disturbance vary over a limited range. The model following variable structure control method is used for controlling front and rear wheels steering of the actual vehicle, so that the steering characteristics of uncertain vehicle model can follow the characteristics of reference model. Simulation results have demonstrated that the control system can overcome the drawbacks of parameter perturbations and outer disturbance.