空间相机桁架式支撑结构的集成优化设计
Integrated optimization design of truss-supporting structure for space camera
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摘要: 桁架式支撑结构在大中型离轴三反(TMA)空间相机中使用广泛,如何提高其动力学特性是此类相机研制过程中的关键。针对桁架结构的设计问题,提出了通过集成优化确定桁架结构动力学特性最佳位置的方法,使用实验设计的手段,对影响其动力学特性的各桁架杆位置变量进行了研究,分析了该优化问题解空间的特点;为了实现桁架结构的全局最优设计,以提高支撑结构的一阶自然频率为目标,使用多岛遗传算法(Multi-island GA)进行全局寻优求解。利用有限元分析的方法,得到该桁架经优化后的一阶自然频率107.72 Hz,较未经优化的初始结构(83.45 Hz)提升了29%,效果显著。该研究提出的集成优化模型和分析方法为此类桁架结构的设计提出了新的思路。Abstract: Truss-supporting structure was widely used among TMA space camera of large or middle size, and how to improve its dynamics characters was the key to the study of cameras alike. As to the design problem of truss structure, bring forward a method of ascertaining the position of the trusses via integrated optimization, study the influence of position variables of the trusses on dynamics characters via designed of experiment, analysed the characteristic of its resolution space. In order to realize whole-space optimized designed of truss, used multi-island genetic algorithm to find the bested resolution, with the objective of improving the 1st-frequency. Used FEM method, find the 1st-frequency of optimized design was 107.72 Hz, which was 29% improved compared with original design(83.45 Hz). The integrated optimization modeling and the analysis method in this study offer a new way for the design of truss structure.