针对某微型光学载荷主结构质量过重, 地面重力变形过大以及基频太低的问题, 提出以质量最小、随机加速度响应RMS值为目标, 基频、变形为约束条件, 建立优化数学模型, 并对光学载荷主结构进行拓扑优化设计。对优化后的主结构进行工程分析, 结果表明, 优化后主结构质量为12.5 kg, 降低了68.71%; 基频由优化前的11.18 Hz提高到268.7 Hz; 最大变形为0.3 μm; 光学载荷安装位置随机加速度响应值放大倍率1.2, 小于总体指标1.5; 最后对主结构和其上端安装的光学载荷进行了力学试验、热循环试验, 并对试验后的设备进行了性能检测, 结果满足总体指标, 证明了所设计的主结构具有良好的性能, 同时该主结构优化方法有效可行。

Aiming at the problems that the main structure of a mini-optical device in space is too heavy, the ground gravity deformation is too large and the base frequency is too low, the optimization mathematical model was established with the objective of minimum mass and RMS of the random acceleration response, the fundamental frequency and the deformation as the constraint conditions. The topology optimization design of the main structure of the mini-optical device and the engineering analysis of the optimized main structure were carried out. The results show that the mass of the main structure of mini-optical device is 12.5 kg, which is reduced by 68.71%; The fundamental frequency is increased from 11.18 Hz to 268.7 Hz after optimization; The maximum deformation is 0.3 μm. The magnification of the acceleration response of the optical-load installation is 1.2 which is better than system specification 1.5. Mechanics and thermal experiments were carried out to examine the performance of the main structure of mini-optical device. The detection results meet the overall index, which proves the main structure has good performance, the optimization method is effective and feasible.