Vehicle Yaw Stability Control via Piecewise Control Strategy

The vehicle handling stability can be improved effectively by the yaw stability control system. Generally, the selection of controller input signals will affect the reliability, applicability and practicability of the yaw stability control system. To reduce the influence of the measurement error or estimation error of input signals on the system, reduce the complexity of the system, and improve the applicability of the system under different driving conditions, a piecewise control strategy based on input signal switching is proposed in current research. Firstly, the time-domain characteristics of the yaw rate and the sideslip angle of the vehicle are analyzed. Secondly, a regional division method with a piecewise control strategy is proposed and illustrated by a simulation test in CarSim. The control region is divided into three regions that are sideslip angle direct yaw moment control (DYC), yaw rate DYC control and integrated DYC control. The control-switching boundary between segments is determined by steering wheel angle, speed and road adhesion coefficient. Combined with a three-degree-of-freedom vehicle model, a robust proportion integral differential (PID) controller is designed. Finally, a simulation model was built, and the effectiveness of the piecewise control strategy and the robust controller is verified.