Precompensation decoupling control with H∞ performance for 4WS velocity-varying vehicles

In this paper, a new decoupling control strategy with H_∞ performance for the three-degree-of-freedom model, including the longitudinal velocity, the lateral velocity, and the yaw rate is presented and discussed. A sliding mode controller only depending on the longitudinal velocity for the longitudinal system and a precompensation decoupling controller with H_∞ performance for the steering system are designed. These controllers are established by feeding back longitudinal velocity and yaw rate, thus observation or measurement for the lateral velocity is not required. Simulation results show that our strategy can improve the handling characteristics, safety, and comfort significantly.