空间热环境下反射镜支撑结构点阵轻量化设计

Lattice Lightweight Design of Reflector Support Structurein Space Thermal Environment

以太阳同步轨道卫星搭载的反射镜系统为研究对象,采用三维点阵胞元填充反射镜支撑架,建立了对应的反射镜有限元模型。为保证结构工作性能,同时考虑装置自身电子元器件自身工作时发热周期与轨道热周期不同步的影响,对反射镜系统进行轨道热分析,确定高低温恶劣工况作为结构分析温度载荷,对反射镜支撑架点阵夹层结构进行尺寸优化设计。优化目标为系统在极恶劣温度工况下反射镜安装平面法向与理想安装轴线间的夹角最小同时支撑架结构质量最小,约束条件为采用点阵结构的反射镜系统基频不小于给定的参考频率。采用多目标遗传算法(MOGA)进行点阵结构的尺寸优化。结果显示,反射镜系统采用优化后的点阵夹层支撑架设计较实体结构基频提高,质量明显降低,同时系统镜片支撑架受热变形后的姿态误差角减小,证明设计的可行性。

This paper took the mirror system carried by the sun-synchronous orbit satellite as the research object,used three-dimensional lattice cells to fll the mirror support frame,and established the corresponding finite element model of the mirror.In order to ensure the working performance of the structure,and at the same time,considering the influence of the heating cycle of the electronic components of the device itself and the thermal cycle of the track when it is working,the orbital thermal analysis of the reflector system was carried out,and the harsh working conditions of high and low temperatures were determined as the structural analysis temperature load.Mirror support frame lattice sandwich structure was optimized for size design.The optimization goal is that the angle between the normal direction of the mirror installation plane and the ideal installation axis of the system under extremely severe temperature conditions is the smallest,and the support frame structure is the smallest.The constraint condition is that the fundamental frequency of the mirror system with a lattice structure is not less than the given reference frequency.Multi-objective genetic algorithm(MOGA)was used to optimize the size of the lattice structure.The results show that the optimized lattice sandwich support frame design of the reflector system improves the fundamental frequency of the solid structure and significantly reduces the quality.At the same time,the posture error angle of the system lens support frame is reduced after thermal deformation,which proves the feasibility of the design.