GEO激光通信系统主镜组件优化设计

为保证GEO激光通信系统主镜的面形误差、主镜组件的结构刚度满足设计要求，需要进行主镜组件结构参数优化设计。由于组件的结构参数较多，为避免参数之间重复优化，提高优化设计效率，采用正交优化方法，用9种结构参数组合完成全部81种参数组合的主镜优化设计，保证了1 g重力、2℃径向温差分别作用时的面形误差RMS值满足RMS/50（=632.8 nm）的面形精度要求，并且改善了5℃均匀温升作用下的面形误差RMS值；在此基础上，进行了柔性支撑优化设计。仿真分析表明，主镜组件一阶频率为213 Hz，高于要求的200 Hz固有频率，主镜在1 g重力、2℃镜体径向温差和5℃均匀温升共同作用下的最大面形误差为10.78 nm，满足面形精度要求。经实验测试:5℃均匀温升的面形误差RMS值为7.27 nm，优于设计要求。优化设计为主镜组件的设计、加工、装校提供了技术支撑。

Optimal design of primary mirror subassembly in GEO laser communication system

In order to meet the requirements of the surface error RMS value and stiffness of GEO(Geostationary Earth Orbit) laser communication primary mirror subassembly, the subassembly structure was optimized. Firstly, the optimal design of 9 group parameter combination of primary mirror was conducted by orthogonal optimization method, instead of total 81 group combination, avoiding repeating parameter optimization and heightening the efficiency of optimal design, in which the surface error RMS value on 1 g gravity and the one on 2℃ radial temperature difference were satisfied with /50(=632.8 nm) surface error demand, the RMS value under 5℃ uniform temperature rise can be improved. Secondly, the flexure support was optimized. The simulation result showed that the first order fundamental frequencies is 213 Hz, superior to 200 Hz fundamental frequency, the maximum surface error RMS values of 1 g gravity on three directions, 5℃ uniform temperature rise and 2℃ radial temperature difference is 10.78 nm, lower than surface error demand. The test demonstrated that the RMS value under 5℃ uniform temperature rise is 7.27 nm, less than design requirement. The optimal design provided technical support to process and alignment of primary mirror subassembly.