Research on variable damping and stiffness magnetorheological dynamic vibration absorber for whole-spacecraft

Abstract Satellites are subjected to various complex and harsh time-varying loads during the launch phase. These loads will cause satellites’ broadband violent vibration. It is an effective method to reduce the vibration response of satellites by installing dynamic vibration absorbers (DVAs) on the vibration isolation platform of the whole-spacecraft. In this paper, the concept of variable damping and stiffness is introduced into DVAs to broaden the vibration absorption bandwidth of traditional DVAs. The structural scheme of the variable damping and stiffness magnetor-heological DVA (VDS-MRDVA) is proposed. MR fluid porous fabric is utilized to achieve the regulation of damping and stiffness. It can effectively solve the sedimentation problem of MR fluid, and it does not require sealing, making the structure of the VDS-MRDVA more compact. The mechanical models of the VDS-MRDVA are established and analyzed. Subsequently, the key structural parameters of the VDS-MRDVA are designed. And the output mechanical properties of the VDS-MRDVA are tested, the test results reveal that the VDS-MRDVA has excellent controllable variable damping and stiffness characteristics. The adjustable damping ratio and stiffness ratio are 24.47 and 1.904 respectively. Finally, the whole-spacecraft vibration absorption simulation and test are carried out. The simulation results demonstrate the advantages and effectiveness of the VDS-MRDVA. And the experimental results show that the VDS-MRDVA exhibits distinct vibration absorption performance under different stiffness and damping. The peak acceleration is reduced by 32.75% when the variable damping current is 0 A, while the acceleration at the satellite’s resonance frequency decreased by 44.74% when the variable stiffness current is 2 A. These results demonstrate significant vibration absorption effectiveness.