单反式光端机反射镜柔性支撑参数化设计与试验

为保证单反式光端机指向捕获跟踪(Pointing, acquisition and tracking, PAT)时反射镜在恶劣空间环境下的面形精度,设计了一种底面开槽的柔性支撑结构。由于柔性支撑结构参数较多,为避免各参数之间严重耦合,采用正交优化方法对柔性支撑结构进行参数优化设计,再利用有限元方法对反射镜组件进行热力学特性分析。仿真分析结果表明,反射镜组件一阶频率为352.61 Hz,在1g重力和10℃温升(温降)共同作用下的最大面形误差RMS为λ/54.79(λ=623.8 nm),能够满足动、静态刚度和热尺寸稳定性要求。使用ZYGO干涉仪在(20±10)℃温度范围内对反射镜面形进行检测,结果表明,反射镜面形PV值优于λ/6,RMS优于λ/43,满足RMS≤λ/40的指标要求。实验结果表明,柔性支撑参数设计可靠,满足使用要求。

Parametric design and test of flexible support for mirror of single trans optical terminal

In order to ensure the surface accuracy of the Pointing, Acquisition and Tracking (PAT) mirror in the harsh space environment, a flexible support structure with grooves on the bottom was designed. Due to the large number of parameters of flexible support structure, in order to avoid serious coupling between parameters, the orthogonal optimization method was used to optimize the parameters of flexible support structure, and then the finite element method was used to analyze the mechanical and thermal characteristics of mirror components. The simulation results show that the first-order frequency of the mirror module is 352.61 Hz, and the maximum surface error RMS under the combined action of 1 g gravity and 10 ℃ temperature rise (temperature drop) is λ/54.79(λ=632.8 nm), which can satisfy the dynamic and static stiffness and thermal dimensional stability. The ZYGO interferometer is used to detect the mirror surface shape in the temperature range of (20±10) ℃. The results show that the PV value of the mirror surface is better than λ/6, and the RMS is better than λ/43, which meets the requirement of RMS≤λ/40. The experimental results show that the design of flexible support parameters is reliable and meets the application requirements.