一种大径厚比低温分光片支撑结构的设计与试验  

Design and Test for a Cryogenic Beamsplitter Support Structure with Large Aspect Ratio

作　　者：童卫明 马越[1] 宋俊儒[1] 晋利兵 练敏隆[1] TONG Weiming;MA Yue;SONG Junru;JIN Libing;LIAN Minlong(Beijing Institute of Space Mechanics&Electricity,Beijing 100094,China)

机构地区：[1]北京空间机电研究所,北京100094

出　　处：《航天返回与遥感》2024年第3期19-27,共9页Spacecraft Recovery & Remote Sensing

摘　　要：空间相机大径厚比低温分光片支撑结构设计时,需要在刚度和柔度方面进行平衡,既要保证能通过力学振动考核,同时还要保证低温下面形精度。针对这一需求,文章设计了一种新的支撑结构,利用不同结构材料热膨胀系数差异进行变形适配,实现无热化支撑,同时在不同材料连接环节设计多级径向柔性卸载结构,实现分光片高刚度、高低温面形精度支撑。对该结构进行了仿真分析,结果表明:分光片组件一阶基频达到191 Hz,从常温293 K到工作温度133 K,分光片面形RMS变化0.032λ(λ=632.8 nm)。该结构的低温面形测试结果显示:温度从293 K降到130 K,分光片面形RMS变化0.028λ。分光片组件随相机主体完成鉴定级力学试验考核,分光片组件安装点最大加速度响应达到16gn,试验前后分光片组件状态无变化。文章设计的大径厚比低温分光片支撑结构刚度、低温面形精度和环境适应性均满足空间相机应用要求。Mounting large radius-to-thickness ratio beamsplitters for cryogenic space application requires a careful trade-off in stiffness and flexibility design.Both the cryogenic wavefront error and the survivability in launch vibration environments should be satisfied simultaneously.A new support structure is designed in this paper.In the design,the difference of thermal expansion coefficient of different structural materials is used to achieve athermal support.At the same time,multistage radial flexible structures are designed at the connection positions of different materials.The support structure achieves both high stiffness and low cryogenic wavefront error.The simulation results show that the first mode frequency is 191 Hz.The wavefront error changes 0.032λfrom 293 K to 133 K based on FEM simulation results.After the beamsplitter is assembled,the cryogenic wavefront error and vibration tests are carried out.The wavefront error changes 0.028λfrom 293 K to 130 K.The maximum acceleration response reaches 16gn at the installation position of the beamsplitter assembly.There is no change for the beamsplitter assembly before and after the vibration test.The stiffness,cryogenic wavefront error and environmental adaptability of the support structure of the cryogenic larger radius-to-thickness beamsplitter in this paper meet the application requirements of space cameras.

关 键 词：低温 分光片 柔性卸载 无热化 面形 支撑结构 

分 类 号：V19[航空宇航科学与技术—人机与环境工程] TN214[电子电信—物理电子学]