A sliding mode control of a full-car electrorheological suspension system via hardware in-the-loop simulation

This paper presents a feedback control performance of a full-car suspension system featuring electrorheological (ER) dampers for a passenger vehicle. A cylindrical ER damper is designed and manufactured by incorporating a Bingham model of an ER fluid which is commercially available. After evaluating field-dependent damping characteristics of the ER damper, a full-car suspension system installed with four independent ER dampers is then constructed and its governing equation of motion, which includes vertical, pitch, and roll motions, is derived. A sliding mode controller, which includes vertical, pitch, and roll motions, is derived. A sliding mode controller, which has inherent robustness against system uncertainties, is then formulated by treating the sprung mass as uncertain parameter. For the demonstration of a practical feasibility, control characteristics for vibration suppression of the proposed ER suspension system are evaluated under various road conditions through the hardware-in-the-loop simulation (HILS).