Switched anti-roll control design for hydraulically interconnected suspension system with time delay

Abstract

To improve a vehicle's anti-roll performance while consuming less energy, an active/passive dual-mode switched control method based on a hydraulically interconnected suspension (HIS) is proposed. This method has two key components as follows: modelling the “mechanical-liquid-gas” coupled dynamic system consisting of hydraulic cylinders, a hydraulic pump and accumulators; and robustly controlling a time-delayed system with uncertain model and lag time. In this study, the nonlinear characteristics of the underlying actuators were considered, and a four degrees-of-freedom (4DOF) roll-plane half-car model was employed. The backstepping algorithm was adopted to maintain the body in the desired posture. Subsequently, a modified Smith predictor and a Taylor expansion of lateral acceleration were applied simultaneously to compensate for the time delay. Finally, simulations with uncertain parameters and lag time were performed. The results indicate that the proposed method is robust in the case of an uncertain control system and can effectively improve the vehicle's anti-roll performance.