Design and Performance Evaluation of MR Damper for Integrated Isolation Mount

This article presents a new type of a MR damper designed for an integrated isolation mount for an ultraprecision manufacturing system. The vibration sources of the ultraprecision system can be classified as two: one is environmental vibration from the floor, and the other is transient vibration occurred from the stage movement. The transient vibration occurred from the stage movement has adverse effect to the manufacturing process because the vibration scale is quite larger than other vibrations. It is also known that the moving stage needs to be isolated from tiny vibrations to be occurred from the floor. Therefore, in this research in order to attenuate both the transient and tiny vibrations, a new type of MR damper is proposed and its performance is evaluated. The proposed MR damper can eliminate a dry friction of the damper to remove the tiny vibration as well as can produce enough damping force to attenuate the transient vibration. The MR damper is designed on the basis of Bingham model of a MR fluid and manufactured. Subsequently, the field-dependent damping force characteristics of the MR damper are evaluated through simulation and experiment. In addition, vibration control performance of the proposed MR damper is evaluated by integrating the damper with a 2 degree of freedom (DOF) stage model. In this evaluation, both transient and sinusoidal vibrations are controlled by adopting both a skyhook controller and a sliding mode controller.