Ride Quality Evaluation of Railway Vehicle Suspension System Featured by Magnetorheological Fluid Damper

This paper presents a semi-active suspension system using magnetorheological (MR) fluid damper for improving the ride quality of railway vehicle. In order to achieve this goal, a fifteen degree of freedom of railway vehicle model, which includes car body, bogie frame and wheel-set is proposed to represent lateral, yaw and roll motions. The MR damper system is then incorporated with the governing equation of motion of the railway vehicle which includes secondary suspension systems. A dynamic of the track irregularities is also developed under external excitation which is the creep force between wheel and rail. In order to demonstrate the effectiveness of the proposed MR dampers on railway vehicle secondary suspension system, the sky-hook control law using the velocity feedback is formulated. Subsequently, the acceleration responses of the car body of the railway vehicle with semi-active secondary suspension system integrated with MR dampers are evaluated under track irregularities. This semi-active controlled system is compared to the uncontrolled motion (passive suspension system) through the analytical method. The simulation results show that the ride quality of the car body of railway vehicle with semi-active controlled MR dampers is feasible.