设计了一种精密电动反射镜架的机械结构,通过微驱动装置的设计调试以及并联驱动机构的解耦运算,使设计的电动反射镜架达到±7.5 mrad的运动行程、0.3 μrad的单步分辨率。对反射镜架进行了有限元模态分析,得到了其固有频率及所对应的模态振型;在此基础上,对电动反射镜架的动态特性进行了实验测试,根据模态分析与动态特性测试的结果,对反射镜架进行了随机振动分析,验证了反射镜架在地脉振动影响下的稳定性指标优于0.5 μrad。

In this work, the design of the mechanical structure of a precision electric mirror frame is realized. Through the design and debugging of a micro-drive device and the decoupling operation of the parallel drive mechanism, the motorized mirror frame designed in this work achieves a motion stroke of ±7.5 mrad and a single-step resolution of 0.3 μrad. The finite element modal analysis of the mirror frame was conducted to obtain the natural frequency and the corresponding mode shape. Based on this analysis, the dynamic characteristics of the electric mirror frame were tested experimentally. Using the results of the modal analysis and dynamic characteristics test, the random vibration analysis of the mirror frame was conducted, revealing that the stability index of the mirror frame under the influence of ground pulse vibrations is better than 0.5 μrad.