双层环形可展开天线机构设计与力学分析

Mechanism design and mechanical analysis of a double-layer loop deployable antenna

为解决超大口径可展开天线机构的轻量化、高刚度设计问题,提出一种由弹性铰链驱动的双层环形可展开天线机构.建立天线结构的静力学分析模型,得出结构中杆件与拉索的相互影响关系,推导出对角拉索预紧力的取值范围.基于建立的双层环形可展开天线结构动力学分析模型,对比分析前6阶振动频率及其相应的模态振型,与无拉索相比,通过对角斜拉索刚化可以将结构刚度提高1.2倍.分析结构参数对结构振动频率的影响规律,基于振动频率影响因素的灵敏度分析,得出增加双层环形可展开天线机构中的横杆截面面积和斜拉索的截面积,减小纵杆截面面积是提高双层天线结构振动频率的有效措施.

A double-layer loop deployable antenna mechanism driven by elastic hinge was proposed to solve the design problem of over-large deployable antenna with high stiffness and light weight. The static analysis model of the antenna structure was established to get the interactional relationship between the bars and cables in this structure and the value range of the pre-tightening force in diagonal cables. The first six order vibration frequency and their relevant modal shapes of these two kinds of the antenna structures were assessed by dynamic analysis. In addition,it was found that the stiffness of the antenna structure with cables is 1.2 times of that of the cable-free structure. The effects of structural parameters on vibration frequency were pointed out,as well as the effective strategies to improve the vibration frequency of the antenna structure based on the sensitivity analysis of factors. It is found that the vibration frequency of the antenna structure can be improved by increasing the cross-sectional area of the transverse bar and the stay cable and reducing the cross-sectional area of the longitudinal bar.