Vehicle Passes a Sharp Curve Through Four-Wheel Steering and Oversteering

The stability and safety of vehicle lateral motion have been studied extensively. However, the research on vehicles passing through sharp curves at relatively fast speed is slightly insufficient. Through previous research, it can be found that the steering characteristics of the vehicle can be changed by changing the cornering stiffness of the front and rear wheels. At the same time, the appearance of four-wheel steering (4WS) vehicles has greatly improved the turning performance of vehicles. Therefore, this paper explores two possible ways to facilitate traffic on roads with smaller radius and compares their effectiveness. We designed a robust controller for 4WS vehicles, which can make full use of the rear wheel steering and the yaw moment generated by the independent drive wheel-hub motor. We also explored ways to change the cornering stiffness of the tire by inflation/deflation system during driving. The simulation analysis shows that both methods proposed in this paper can help the vehicle pass the curve with relatively faster speed and smaller turning radius. But 4WS vehicles equipped with robust controllers have smaller turning radius than front wheel steering (FWS) vehicles equipped with tire inflation/deflation systems, so 4WS vehicles perform better through sharp curves.