Lateral Stability Control of Four-wheel Steering Vehicles

This study aims to reduce the side-slip angle and the error of tracking the ideal yaw rate of four-wheel-steering (4WS) vehicles. A fuzzy PID (Proportion Integration Differentiation) controller is used to control the rear wheel angle. We choose yaw rate deviation as PID controller input; the fuzzy controller sets the yaw rate deviation and deviation change rate as inputs, and the output of the fuzzy controller is used to correct the PID parameters. The output of the 4WS system controller is the rear wheel angle that reduces the yaw rate deviation. We adopte the CarSim/Simulink co-simulation platform. The front wheel steering two-degree-of-freedom vehicle model is selected to be the reference model, and the CarSim vehicle model is used as the controlled object to perform simulation experiments. Simulation results show that the controller can reduce the error of yaw rate tracking and improve the stability of vehicles.