考虑桁架变形的可展开天线索网结构多目标优化设计

Multi-objective Optimization Design of Cable Net Structure for Deployable Antenna Considering Truss Deformation

索网结构是可展开天线的重要组成部分,在桁架的支撑下,索网结构的前/后索网和竖向索阵处于张紧状态,形成满足精度要求的工作反射面。本文提出了一种可以考虑桁架变形的索网形态设计方法。首先,基于索网结构的平衡矩阵奇异值分解,约束索段张力并以索力均匀为目标,通过优化求解找到一组最优预张力。将索网挂接在桁架上,以索段的预张力和前索网节点的位置增量为设计变量,以直接与桁架连接索段的张力改变量的均方根值,索段预张力均匀性和反射面形面精度为目标,约束索段张力和节点位置增量的取值范围,建立了索网结构多目标优化模型。最后通过相应算例,验证了方法的正确性。

The cable net structure is an important part of the deployable antenna,under the support of the truss,its front/rear cable net and vertical cable array are in a tension state,forming a working reflective surface that meets the required precision.In this paper,a design method of cable net considering the deformation of truss is presented.First,based on the singular value decomposition of equilibrium matrix of cable net structure,the tension of cable segment is constrained and the uniformity of cable force is taken as the objective,and a set of optimal tension is found by optimizing solution.Then,the cable net is connected to the truss,the multi-objective optimization model of cable net structure is established by taking the tension and the node position increment as design variables,and taking the root mean square of the tension change of the cable segment directly connected to the truss,the uniformity of the tension and the accuracy of the reflector surface as the objectives,and also constraining the range of the cable segment tension and the node position increment.The method presented is programmed for a corresponding example at last,and the results indicate that the method is feasible.