基于增材制造的空间反射镜拓扑优化设计  

Topological optimization design of space mirror based on additive manufacturing

作　　者：刘多 江昱含 董得义[2] 孙宝玉[1] 关英俊[1] LIU Duo;JIANG Yu-han;DONG De-yi;SUN Bao-yu;GUAN Ying-jun(School of Mechanical and Electrical Engineering,Changchun University of Technology,Changchun 130012,China;Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033,China)

机构地区：[1]长春工业大学机电工程学院,吉林长春130012 [2]中国科学院长春光学精密机械与物理研究所,吉林长春130033

出　　处：《机电工程》2022年第7期1010-1016,共7页Journal of Mechanical & Electrical Engineering

基　　金：国家自然科学基金资助项目(11873007,12073028);中央引导地方科技发展基金资助项目(202002035JC)。

摘　　要：传统的空间反射镜存在研制周期长、成本高的问题,为了缩短反射镜的研制周期并节约成本,将拓扑优化与增材制造技术相结合,以满足反射镜面形精度要求为前提,对高轻量化率的反射镜结构进行了拓扑优化设计与增材制造。首先,在确定反射镜材料和初始参数后,建立了反射镜的拓扑优化数学模型,并在拓扑优化中引入了可制造性约束,获得了满足面形精度要求的反射镜背部创新加强筋结构;然后,对反射镜模型进行了有限元分析,分析了缩比模型与原尺寸模型的等效性;最后,采用选区激光熔化技术,以AlSi10Mg铝合金粉末为材料,进行了反射镜缩比模型增材制造试验。研究结果表明:在自重载荷下,光轴竖直方向裸镜面形精度达到峰谷值164.3 nm,均方根值27.6 nm,优化后的反射镜质量为4.75 kg,轻量化率达到了85%,实现了反射镜高轻量化率设计;采用增材制造技术后,获得了高度还原拓扑优化反射镜结构的效果,可为空间反射镜的高效研制提供参考。The traditional space mirror has the problems of long development cycle and high cost.In order to shorten the development cycle of the mirror and save the cost,the topology optimization and additive manufacturing technology were combined.On the premise of meeting the requirements of the shape accuracy of the mirror,the topology optimization design and additive manufacturing of the mirror structure with high lightweight rate were carried out.Firstly,the mathematical model of the topology optimization was established after determining the material and initial parameters of the mirror,and the manufacturability constraint was introduced into the optimization,the innovative stiffener structure at the back of the mirror meeting the requirements of surface accuracy was obtained.Then,the finite element analysis was carried out.The equivalence between the reduced scale model and the original size model was studied.Finally,the fabrication experiment of mirror scale model additive was carried out with AlSi10Mg aluminum alloy powder by selective laser melting(SLM)technology.The results indicate that the shape accuracy of the bare mirror in the vertical direction of the optical axis reaches peak value(PV)=164.3 nm,root mean square(RMS)=27.6 nm under the self weight load,the optimized mirror mass is 4.75 kg,and the lightweight rate reaches 85%,the high lightweight design of the mirror is realized according to the finite element analysis.After adopting additive manufacturing technology,the effect of highly restoring topology optimization mirror structure is achieved,which provides a new way for the efficient and rapid development of space mirror.

关 键 词：大口径空间反射镜 面形精度 拓扑优化 数学模型 选区激光熔化技术 可制造约束 

分 类 号：TH74[机械工程—光学工程] TP391.7[机械工程—仪器科学与技术]