Smart control of vehicle-bridge system using MR dampers

To study the feasibility of vibration control of vehicle-bridge system, the system is simplified as the problem of a moving oscillator traversing an elastic continuum. The control device is placed in parallel with spring and dashpot elements that comprise the suspending part of the vehicle. Two different control schemes are investigated, namely ideal active control and semi-active control by using MR damper. A hysteretic model based on a normalized Bouc-Wen model is developed. for the MR damper and verified through lab test. The control objective is to reduce the bridge deflection and the vehicle acceleration. A Bang-Bang tracking control algorithm is adopted to command the MR. damper. The nominal controller employs H-2/LQG control design with the output feedback of the damper force and the accelerations of the vehicle and the bridge. The numerical results indicate that the performance of semi-active technique is similar to the active control case, while requiring only a fraction of the power.