Abstract: Based on active vibration isolation and precision pointing control of ultra quiet platform for high precision spacecraft in the future, considering the dynamic characteristics of flexure jointed ultra quiet platform, as well as the effect of base and payload disturbances, the general dynamic model of ultra quiet platform is built. Then the decoupled force control method is derived, and the highly coupled multiinput and multioutput system for ultra quiet platform is converted into singleinput and singleoutput linear time invariant system so that the interaction of different struts is eliminated. The method also greatly simplifies the controller design. On this basis, the numerical simulation analysis and verification are made. The simulation results show that the decoupling force control method using a general dynamic model can achieve good control effect for active vibration control of ultra quiet platform, which is simple and easy to implement.

Key words: ultra quiet platform, dynamic modeling, decoupled force control, flexure jointed