Research On Micro-vibration Dynamics On Satellite Based On Stewart Platform With The Flexible Beam

In recent years, the high-precision instruments are used more and more widely in the field of aerospace, which put forward higher requirements to the spacecraft’s ability to adapt to the complex environment. For example, the loading of high-resolution camera on the high resolution remote sensing satellite need the better "super quiet" mechanical environment, thus inhibiting the development of micro-spacecraft vibration technology is of great strategic significance.Stewart platform is a high-precision multiple degrees of freedom vibration isolation platform, its kinetic analysis helps in-depth study of vibration isolation technology. In this paper, applying the flexible cantilever beam of the Stewart platform,including natural frequency, transfer function, dynamics mode shapes and dynamic response, dynamic characteristics analysis of the specific as follows:(1) Using the matrix form of the Kane method establishes the nonlinear dynamics model of Stewart platform of vibration isolation with a flexible cantilever beam, and based on the characteristics of satellite micro-vibration and microgravity we ignore the geometric nonlinear term in the equation a. And then according to the linear assumption of actuators axial force, we established the working space form of linear dynamic model of the platform.(2) The linear dynamics model was programmed through MATLAB,using ADAMS established the rigid-flexible coupling simulation model of isolation platform, we get the analytical results and software results of the inherent frequency and the transfer function of the system and verify the correctness of the theoretical model and coupling systems. We also analyze the effect of the presence of cantilever beam and the location of cantilever beam relative to the center of mass of the platform on the natural frequency of the platform as a whole, the effect of the location of cantilever beam relative to the center of mass of the platform on the vibration modal,the effect of the location of cantilever beam on dynamic response at the top of the cantilever beam and the effect of the rigid and flexible bar on its dynamic response at the top of the cantilever beam under the same basic motivation.(3)According to the all components of given size build a Stewart platform with flexible cantilever beam and make the longitudinal sine sweep experiment,which measured the longitudinal acceleration transfer function, compared with the longitudinal simulation results, we once again validate the theoretical model correctness.