超轻反射镜柔性支撑结构设计与试验

Design and Test of Flexible Supporting Structure for Ultra-light Mirror

针对微型遥感载荷超轻反射镜柔性支撑问题,提出了一种折臂梁式柔性支撑结构.根据反射镜结构特点,建立柔性支撑结构的参数化模型.采用第二代非支配排序遗传算法建立了多约束多目标的参数优化模型,对柔性结构关键参数进行了优化,最小尺寸仅为1.30 mm.对反射镜与柔性结构粘接面积的强度进行了校核,安全裕度为3.6.并对反射镜组件进行了工程分析和力学试验,所设计的柔性结构能够在1g重力和温度4℃变化时保证超轻反射镜具备优于3 nm的面形精度,仿真分析与力学试验相对误差均在10%以内.最后,对反射镜组件进行了镜面的面形检测,力学振动试验前后,镜面的表面误差RMS均为0.020λ,表明该反射镜组件稳定性良好.本文提出的折臂梁式柔性支撑结构设计方法是可行的,结构性能是可靠的.

Facing the flexible support problem of the ultra-light mirror for micro-remote sensing payloads,a flexible support structure with folded-arm beam was proposed.According to the structural characteristics of the mirror,a parametric model of the flexible support structure is established.The second-generation non-dominated sorting genetic algorithm is used to establish a multi-constrained and multi-objective parameter optimization model.The key parameters of the flexible structure are optimized.The minimum size is only 1.30 mm.The strength of the bonded area is checked and the safety margin is 3.6.Finally,the engineering analysis and mechanical test of the mirror assembly are carried out.The flexible structure designed can ensure that the surface accuracy of the ultra-light mirror is better than 3 nm,when it is under the gravity and temperature is changed by 4℃.The relative error of simulation analysis and mechanical test is less than 10%.Finally,the mirror surface accuracy of the mirror assembly was detected.Before and after the mechanical vibration test,the surface error RMS of the mirror is 0.020λ,indicating that the mirror assembly has good stability.The feasibility of the design method and reliability of the flexible support structure with folded-arm beam proposed in this paper are verified.