Design and Analysis of Rotary MR Damper Using Permanent Magnet

Abstract As a device for vibration suppression or energy dissipation, semi-active systems have both reliability of passive devices and adaptability of active systems. Among the people studying semi-active devices, the interest in the controllable magnetorheological(MR) fluid has been increased dramatically since 1990s. The torque of the damper using MR fluid can be controlled by the magnetic field. In this paper, we propose a valve mode MR damper using permanent magnetic circuit. Because the power consumption at the steady state is reduced, it consumes less power overall. We investigate the characteristics of this damper such as hysteresis and time delay and show the performance by experiments. The experimental results show that the proposed damper has a good tracking performance for step, ramp and sinusoidal trajectories.