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As for the lightweight structure of a large-aperture primary mirror in remote sensors,this paper introduces an optimized multi-target Genetic Algorithm(GA) based on the Kriging approximate model to design all lightweight structure paramaters for a 2 m-aperture SiC primary mirror.The latin hypercube method is used to build the Kriging model and do the experimental design of optimized parameters,and then a optimal solution is obtained through the multi-target GA(NSGA II).After the optimization,the 2 m-aperture SiC primary mirror weights 243 kg,the surface accuracy reaches 25.7 nm PV,4.7 nm RMS and the total lightweight rate is 84%.The experimental result proves the feasibility of this optimization method and it can be a reference for the future lightweight optimization design of the structural parameters of large-aperture primiary mirrors.

A thermal control system for a high-power CCD space camera was designed,including a thermal test of the focal plane assembly for resolving the heat dissipation problem.First,the thermal design scheme of the CCD was examined,where the heat produced by the CCD was transferred to the cold source through a heat pipe.Then a thermal test of focal plane assembly was planned with the simulated cold source specially designed.Finally,the thermal test of focal plane assembly was performed in a vacuum to simulate its space environment and structure characteristics.The results show that the working temperature of a 10 W high-power CCD space camera can be kept below 35 ℃ when it has been working for 70 min continuously and has a 12 ℃ cool source.The thermal design of the CCD focal plane assembly for the space camera is feasible and acceptable.It can be used as a reference for the mode correction of focal plane assembly thermal analysis.

The supporting structure of the large-aperture primary mirror of the space camera is the key technology for the space camera. This paper presents the problem that the ball-hinge supporting structure of a certain type of primary mirror will lead to the astigmatism when the external condition varies. Based on the research on the ball-hinge supporting structure, a novel flexure supporting structure was developed and optimized with numerical analysis. Some environment experiments were conducted, and the results demonstrated that the supporting structure had large dynamic stiffness, and was better suitable for the assembly stress and thermal stress. This flexure supporting structure makes the mirror surface figure stable in a wide temperature range, and the RMS value of 0.02λ(λ=632.8 nm) when the gravitational load varies, which means the design requirement is satisfied.