微小卫星星敏感器支架的优化设计与试验

针对卫星结构中星敏感器支架在随机激励下加速度响应均方根(RMS)值过大的问题,提出了星敏感器支架优化设计方法。简述了星敏感器安装点随机响应的基本理论,对卫星结构进行了模态和加速度响应灵敏度分析。以星敏感器安装点RMS值最小为目标,以基频和体积分数为约束,建立了星敏感器支架随机响应优化模型,并对支架进行了拓扑优化设计。最后,利用MSC.PATRANNASTRAN对优化处理后的支架模型进行了工程分析。结果显示:星敏感器安装点随机响应RMS值降低了20%以上,支架结构轻量化率达到了50%。另外,利用振动试验台对支架进行了振动试验。实验显示:有限元分析结果与试验数据相对误差低于15%,表明设计的支架的性能参数满足设计指标,验证了所采用优化方法的可行性。

Optimization design and test for bracket of star sensor in micro-satellite

An optimization design method for the bracket of a star sensor was proposed to overcome a larger acceleration response value (Root Mean Square(RMS)) under random excitation of a micro-satellite. The basic theory of random response of the star sensor at an installation point was described, and the structure modal and acceleration response sensitivity of the satellite structure were analyzed. By taking the minimum random response RMS value at the installation point as the target, and the nature frequency and volume fraction for the restraint, an optimized model for the bracket of the star sensor was established and the topological optimization was performed for the model. Finally, the engineering analysis was carried out on the optimized model by using MSC.PATRAN& NASTRAN. The results show that the random response RMS value of the star sensor at the installation point has reduced more than 20%, the lightweight rate of the support structure has reached 50%. Furthermore, the bracket of star sensor was tested with a random vibration test platform. The results indicate that the relative error of the finite element analysis results and the experimental data is less than 15%, which shows that the designed performance parameters meet the design requirements and verifies the feasibility of the optimization method.