A parallel mechanism is used as the adjusting mechanism of the secondary mirror for a 2 m magnitude large off axis three mirror space camera. The moving platform of the adjusting mechanism is directly used as a secondary mirror support board,which increases the structural stiffness and makes the whole machine structure more compact. Therefore,the backplane is the core part of secondary mirror assembly. The backplane is made of 60SiC/Al with good dimensional stability and high specific stiffness. Due to the importance of the backplane as a top and bottom support,it has high requirements for its weight and stiffness,so the topology optimization design is carried out with the stiffness as the target,and the multi objective size optimization of the backplane panel and a stiffener is carried out with the backplane quality and fundamental frequency as the target. The optimized backplane has a mass of 1.42 kg and a fundamental frequency of 954 Hz. Finally,statics and dynamics analysis of the secondary mirror module is carried out. The results show that the gravity direction displacement and surface RMS values are the largest under the coupling gravity and 4°C temperature rise conditions:The maximum displacement is 9.651μmand the RMS value of the surface is 7.535 nm. The first order natural frequency in the constrained state of the secondary mirror assembly is 115 Hz,which meets the requirements for in orbit imaging of large space telescopes.
参考文献
相似文献
引证文献
引用本文
程明星,李威,赵伟国,赵海波.大型空间望远镜次镜背板的优化设计[J].激光与红外,2023,53(1):101~107 CHENG Ming-xing, LI Wei, ZHAO Wei-guo, ZHAO Hai-bo. Optimal design of secondary mirror backplane for large space telescope[J]. LASER & INFRARED,2023,53(1):101~107