空间遥感器的大口径反射镜的设计目标是高比刚度。为限制发射成本, 尽可能降低镜体质量; 为保证反射镜的功能需求, 尽可能提高镜体自身的刚度, 随着反射镜口径的增大, 反射镜的轻量化设计更加重要。针对某Φ2 m口径天基大口径反射镜镜体的轻量化设计, 采用了传统经验设计、拓扑优化设计和尺寸参数优化设计相结合的综合优化设计方法, 相对大口径反射镜镜体的传统轻量化设计方法, 这种综合优化设计方法可使设计结果快速收敛, 获得最优化的设计结构。采用综合优化设计方法完成镜体的优化设计后, Φ2 m口径天基大口径反射镜镜体的质量为326 kg, 镜体轻量化率高达82.5%, 单镜在光轴竖直状态, 在1 g重力载荷作用下, 取决于镜体刚度的评价镜体成像质量的镜面面形精度RMS值的变化量优于4.9 nm, 单镜在光轴水平状态, 在1 g重力载荷作用下, 镜面面形精度RMS值的变化量优于4.3 nm。结果表明, 镜体质量优于设计要求的340 kg; 镜面面形精度RMS值变化量优于设计要求的5 nm, 满足了镜体要求的高比刚度要求。

The design goal of the large-diameter reflector used in the space remote sensor is high specific stiffness. In order to limit the launch costs, reduce the mass of reflector as far as possible and ensure the function requirements of the reflector, improve the structure stiffness of the reflector itself as much as possible, the reflector lightweight design is more important along with the rise of the reflector aperture. In this paper, aimed at the lightweight design of some Ф2 m-level space-based large-diameter reflector, the integrated optimization design method, which was a combining method with the traditional experience design, the topology optimization design and the size parameter optimization design, was applied. Compared with traditional optimization design method of the large-diameter reflector, it can make the design result fast converge, getting the optimal design structure. The mass of the Ф2 m reflector designed with the integrated optimization design method was 326 kg, the lightweight rate of the Ф2 m reflector was as high as 82.5%, the shape error variation RMS of the reflector which characterized the image quality of reflector and depended on the reflector stiffness was 4.9 nm when the reflector optical axis was vertical and the gravity load of 1 g was applied, and 4.3 nm when the reflector optical axis was horizontal and the gravity load of 1 g was applied. The results show that the mass of the reflector is smaller than the design requirement of 340 kg, and that the shape error variation RMS is better than the design requirement of 5 nm, satisfying the requirement of the high specific stiffness of the reflector.