基于等效弹簧式柔性连接的摆镜模态分析

Modal analysis of tilt mirror based on flexible connection of equivalent spring

针对空间稳像系统摆镜的柔性连接方式,提出了使用多个等效弹簧单元替代原有的柔性连接的有限元分析方式。对等效弹簧与原弹簧的弹性系数的对应关系进行了推导,使用等效弹簧的方式对摆镜系统完成了有限元建模,并进行了模态分析,计算出了一阶谐振频率。最后用非接触式激光共振检测系统对摆镜系统进行了检测,并将检测结果与模态分析结果进行了对比,结果表明,基于等效弹簧式柔性连接的摆镜有限元建模方法切实有效。为摆镜的后续设计提供建设性参考,对类似的工程分析具有十分重要的借鉴意义。

For the flexible connection of space image stabilized system, the connection that uses multiple equivalent spring connecting units to replace the original flexible connections was analyzed by the FEA method. And the relation- ship between elastic coefficients of the equivalent spring and the original spring was derived. The finite element model was established for tilt mirror system by using the equivalent spring. After the modal analysis ,first-order resonant fre- quency is calculated. At last, the tilt mirror system is tested through non-contact laser resonance detection system, and test results and modal analysis results were compared. The results show that the finite element modeling method based on equivalent spring flexible connection is effective,which provides a constructive reference for subsequent design of tilt mirror and a very important reference for similar projects.