A new state observer-based vibration control for a suspension system with magnetorheological damper

Abstract

A new state observer-based vibration control strategy for the suspension system equipped with magnetorheological (MR) damper is proposed in this paper. Firstly, the Bouc-Wen model is implemented to fit the hysteresis phenomenon of the MR damper. A new dynamic model is successfully formulated including the Bouc-Wen model and electrical equation. According to the energy conservation law, an adjustable current is designed as the control object to adjust the characteristics of the MR damper to absorb the external input energy. Then, the current is assumed as an unavailable state for the suspension system, a supplemental state observer (SSOB) including the correction function and adaptation law is proposed to estimate it. Finally, a supplemental state observer-based sliding mode control (SSOBSMC) integrated with SSOB and sliding mode control (SMC) is proposed to estimate the unavailable current and perform robust vibration control, simultaneously. From the simulation results, the proposed SSOB shows outstanding state estimation ability for the suspension system. The SSOBSMC also performs outstanding state estimation ability and robust vibration control performance, simultaneously.