关键词: 微动平台, 隔振平台, 模态辨识, 参数摄动, 刚体模态

Abstract: Concerning the parameter model identification problem of the 6-DOF micro-vibration isolation platform, the modal parameters identification method of the 6-DOF isolation platform was analyzed. Simulation of the variation of modal parameters caused by perturbation of the parameters in the theoretical model of the micro-vibration isolation platform was performed based on parameter perturbation re-analysis method, and the effects on modal parameter identification accuracy in modal experiment was analyzed. The results show that weak coupling is generated between part of the uncoupled modals due to unequal of the bearing stiffness in the same direction, which changes the modal frequency and mode of the system; perturbation of the vertical position of the gravity center has large impact on modal frequency of the platform; the impact of perturbation of bearing stiffness and vertical position deviation of the gravity center on modal frequency identification is not obvious, but it has evident effect on identification accuracy of the mode.

Key words: micro-vibration platform, isolation platform, modal identification, parameter perturbation, rigid body modal