Dual-stage vibration isolation of optical payloads for satellites

In order to realize high quality imaging performance for the optical payload of a satellite, a dual-stage passive vibration isolation system is discussed in this paper. The first stage of vibration isolation is at the actuator disturbance source like the control moment gyros (CMGs). The second stage of isolation is placed between the top of the satellite bus and the optical payload. Firstly, an integrated satellite dynamic model is built, including a dual-stage vibration isolation system, pyramid configuration CMGs and solar arrays, and the validity of this dynamic model is verified by ADAMS. Secondly, the satellite system level dynamic model is simplified based on reasonable assumptions. The transfer function matrices from CMGs motion to satellite motion and that to optical payload motion are derived. The influence of the vibration isolation platform of CMGs on the attitude control system is analyzed. Then the frequency domain characteristics of this vibration isolation system are discussed in terms of the rationally selected parameters of the dual-stage passive vibration isolation system. Finally, the rationality of the parameters of the dual-stage vibration isolation system and the feasibility of its application are proved by numerical simulation. The simulation results illustrate the ameliorative effect of the dual-stage vibration isolation system on the attitude stabilization of the optical payload at the frequency of the rotor speed.