In this paper, the lightweight design and analysis of the primary mirror structure for space camera with a diameter of Φ302 mm is carried out. The primary mirror material is glass ceramic and is fixed by peripheral support. It is necessary to minimize the weight of the primary mirror while meeting the complex mechanical conditions during launch and on-orbit. First, through comparative analysis of several lightweight forms, it is determined that the hexagonal honeycomb structure is selected as the final lightweight structural. Secondly, the finite element analysis and Zernike polynomial are used for iterative optimization. Under the condition that the RMS of the primary mirror surface shape accuracy needs to be better than 10 nm, the final result of the primary mirror mass of 5.46 kg and the light weight rate of 30% is obtained. Thirdly, in order to check the environmental adaptability of the primary mirror, statics and dynamics were analyzed. The analysis results show that the structural strength of the primary mirror can withstand 10 g overload acceleration and the first order mode is greater than 500 Hz. Finally, the optical mirror surface of the primary mirror is detected by the interferometer, and the surface shape accuracy RMS is 7.5 nm, which effectively proves the accuracy and reliability of the lightweight design and analysis of the primary mirror. This paper provides ideas and references for the lightweight design of small and medium-caliber mirror structures.
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