Research on Dynamic Characteristics of a Magnetorheological Damper With Decoupling Mechanism

Abstract

Satellites are subject to severe vibrations during flight. These vibrations are induced by multiple sources during liftoff and the instant of final separation. Severe vibrations may cause damage to satellites. For this reason a payload adaptor is needed. Magnetorheological (MR) damper can be utilized to keep the satellites safe. But the common MR damper can’t be used in cases of high-frequency vibrations because of stiffness hardening. For this reason, a new MR damper with decoupling mechanism has been designed by adding a decoupling sheet to the common MR damper. The decoupling mechanism makes the damper sensitive to vibration. This means that the damper has different stiffness and damping in case of different vibration amplitude. Based on the Bingham model, the model of the suggested MR damper has been built, and mathematical formulas has been deduced for dynamic stiffness, delay angle and transmissibility of the damper. Dynamic characteristics have been simulated. The results show that the decoupling sheet doesn’t work in case of low frequency and high amplitude vibration and the damper presents high damping. In case of high frequency and low amplitude vibration, the decoupling sheet works and the damper presents small damping and stiffness. Thus the stiffness hardening has been avoided. Influence of internal sub structure resonance can be reduced by choosing appropriate parameters. This damper can be used for semi-active control of broadband vibration.