星敏感器支撑结构多目标拓扑优化设计与试验

针对微小卫星对星敏感器的特殊要求，结合星敏感器特殊的工作性能和环境，采用拓扑方法对星敏感器支撑结构进行多目标优化设计并进行有限元分析和试验。首先，对模态分析和随机振动响应的基本理论进行介绍，推导出多目标拓扑优化的表达公式；其次，以支撑结构的体积最小和星敏感器在支撑结构上的四个安装点RMS值最小为目标，以最低自振频率为约束，建立支撑结构的拓扑优化模型，利用OptiStruct软件对其进行拓扑优化设计；然后利用MSC.PatranNastran有限元分析软件对优化后的支撑结构进行模态分析和随机振动响应分析，得到基频为327 Hz ，安装点RMS值的放大率最大为1.55；最后，对支撑结构进行振动试验，试验结果和有限元分析结果的相对误差最大为6.68%，二者吻合较好，该星敏感器支撑结构满足微小卫星对其性能指标的要求。

Multi-objective topology optimization design and test for support structure of star sensor

According to the special requirements of star sensor for micro satellite, combined with special working performance and environment of star sensor, multi-objective optimization design was carried out on the support structure of star sensor by using topological method, and finite element analysis and test were also done. First, the basic theory of modal analysis and random vibration response were introduced in this paper. The expression formula of multi-objective topology optimization was derived. Second, the goal of optimization contains volume minimization of the support structure, and RMS value minimization of 4 installation point in the support structure where star sensor was installed. The topology optimization model of the support structure was established under the restriction of the lowest natural frequency. The topology optimization design was carried out by using OptiStruct software. Then, the modal analysis and random vibration response analysis of the optimized support structure were made by using finite element analysis software MSC.PatranNastran. The natural frequency was 327 Hz, the maximum amplification rate of the RMS value of the installation point was 0.55. Finally, the support structure was tested with the random vibration test. The test results are in good agreement with the finite element analysis results, and the maximum error is 0.07. The support structure of star sensor meets the requirements of the performance index for micro satellite.