Semi-active H∞ control of seat suspension with MR damper

The vibration control of a seat suspension system with magnetorheological (MR) damper is investigated in this study. Firstly, a dynamical model of the seat suspension system with parameter uncertainties (such as mass, stiffness, damping) and actuator saturation is established. Secondly, based on Lyapunov functional theory and considering constraint conditions for damping force, the semi-active controller is designed, and the controller parameters are derived in terms of linear matrix inequalities (LMIs), which guarantees H-infinity performance index. Finally, compared H-infinity control strategy and the passive, skyhook control strategy, the simulation results in time and frequency domains demonstrate the proposed approach can achieve better vertical acceleration attenuation for the seat suspension system and improve ride comfort.