Research on Dynamic Modeling and Control of Magnetorheological Hydro-Pneumatic Suspension

A novel magnetorheological semi-active hydro-pneumatic suspension system was proposed to overcome the shortcoming of the traditional hydro-pneumatic suspension without adaptive vibration damping function. It is based on the magnetorheological semi-active vibration reduction technology to effectively improve the ride performance of the vehicle. Firstly, a nonlinear model was established with the Bouc-Wen model based on the mechanical property test results of magnetorheological hydro-pneumatic spring. Secondly, the dynamic model of the single-wheel magnetorheological hydro-pneumatic suspension system was established. Subsequently, the ON-OFF and PID-Fuzzy semi-active control strategies of the single-wheel magnetorheological hydro-pneumatic suspension were proposed based on the ON-OFF and PID-Fuzzy control methods. The simulation results demonstrate that the magnetorheological hydro-pneumatic suspension under PID-Fuzzy control has the best vibration reduction effect in comparison with the passive hydro-pneumatic suspension. The sprung mass acceleration, suspension working space, and dynamic tire deformation are reduced by 24.50%, 21.62%, and 21.01%, respectively. The bench test results verify that magnetorheological hydro-pneumatic suspension and its control methods can effectively improve the ride performance of the system.