Study on the development of a passive type MR damper with displacement-dependent damping characteristics

This paper proposes a new concept of Magneto-Rheological (MR) fluid damper, which is a passive type MR fluid damper. The passive type MR damper has no electrical devices such as sensor, power supply and controller, and hence, it has an advantage in reliability and cost compared with semi-active MR dampers. Moreover, the proposed MR damper can be designed as a variable damping force device in respond to its displacement. In this paper, dynamic performance of a passive type MR damper is experimentally demonstrated. The prototype of the proposed damper has been manufactured in order to verify the dynamic performance. The displacement excitation test result of the damper demonstrates that the damping characteristics depend on its displacement amplitude, that is, the damper behaves as a linear viscous damper under smaller vibrations and develops much higher damping performance under large vibrations.