星载平面可展天线支撑桁架的结构效率优化

针对折展结构性能存在多指标且这些指标之间又相互制约的特点,把结构效率引入到可展结构的优化设计中,应用多因素正交试验法对一种空间可展开平板天线支撑桁架的优化问题进行了研究。对其关键几何设计参数进行了分析,建立了桁架结构的优化数学模型,以结构效率最大化作为优化目标,对可展桁架进行了结构优化,得到了支撑桁架各杆件的设计参数。结果表明:结构效率综合考虑了质量和刚度的影响,使结构质量和刚度同时得到优化;长宽比(l/w)是影响可展桁架结构性能的主要因素,对不同优化目标产生影响的次要因素有所不同;截面积对结构效率影响不显著(置信度p=90%),在相同杆长参数配置下,等截面可展桁架的结构效率仅次于变截面方案,但工程经济性最佳。该研究方法有助于在概念设计阶段从系统设计的角度进行空间桁架结构的快速设计与优化。

Optimization for structure efficiency of a deployable spaceborne truss with flat panel antennas

In view of the multiple indexes and their interactive influences evaluating the structure performances of deployable and foldable panel antennas, the structure efficiency is introduced to the deployable structure optimization, and optimization on structure design is studied by the orthogonal experiment for a space deployable truss. The geometric design parameters are analyzed, and an optimal mathematic model is also built with goals of minimum mass and maximal structural stiffness. Aimed at the structure efficiency maximization, the structure optimization for the space deployable truss is calculated, and the design parameters of truss structure are obtained. It is found that the factors that influence structure efficiency such as mass and stiffness are considered synthetically, and the mass of optimized structure is reduced and the deployment stiffness is improved simultaneously. The most important influencing factor on the structure performance is l/w, and the minor influencing factor varies with different optimization goals. When p=90% the study indicates that area has an insignificant effect on the structure efficiency of a space deployable truss.The structure efficiency of the space deployable truss with variable cross-section is better than that of the one with unique cross-section. However, the space deployable truss with unique cross-section shows more economy under unique linkage dimensions.The proposed method can be helpful for the designer in evaluating the structure performances at the conceptual stage of design from the point of system design.