Design and control of the military vehicle suspension featured by mr damper

This paper proposes a new type of MR (magnetorheological) fluid based suspension system and applies it to military vehicle for vibration control. The suspension system consists of gas spring and MR damper. The MR damper is incorporated with MR valve and disc spring. Firstly, the dynamic model of the disc spring is established with respect to the load and pressure. The nonlinear behavior of the disc spring is incorporated with the damper model. And the dynamic model of the MR valve is derived by considering the pressure drop due to the viscosity and yield stress of MR fluid. The governing characteristics of the proposed MR damper system are then investigated by presenting the field-dependent pressure drop of the MR valve and pressure drop of the disc spring. Secondly, the governing equation of gas spring is developed by its dynamic model. Subsequently, a half car of military vehicle is adopted for the integration of the MR suspension system and its nonlinear dynamic model is established by considering vertical and pitch motion. Then, a sky-hook controller associated with semi-active actuating condition is designed to reduce the imposed vibration. In order to demonstrate the effectiveness of the proposed MR suspension system, computer simulation is undertaken showing vibration control performance such as vertical displacement and pitch angle evaluated under bump road profile.