剪叉联动式双层环形桁架可展开天线机构设计与分析

摘要

为提高环形桁架可展开天线机构的刚度,提出了一种剪叉联动式双层环形桁架可展开天线机构,介绍了其具体结构及特点;对整体桁架机构进行了单元划分,将其分解为多个六面体可展单元,分析了整体桁架结构的运动过程及特点,并对六面体基本可展单元进行了结构分析与简化;基于反螺旋理论分析了六面体可展单元的自由度及运动形式,得到了其只有一个收展运动自由度的结论,最后建立了整体双层环形桁架可展开机构的仿真模型,模拟了整个双层环形桁架机构的收拢与展开过程,验证了其整体的可展性.%A scissors linkage double ring truss deployable antenna mechanism was presented in this paper and a detailed description of the structure was given. The whole truss was divided into multiple hexahedral developable units, the movement process and property of the whole truss was studied, and the structure ( DOF) of the hexahedral developable unit was analyzed and simplified. Then the degree of freedom of the hexahedral developable unit was calculated based on the reciprocal screw theory. The results showed that the hexahedral developable unit only had one DOF. In the end, the simulation model of the whole double ring truss was built, the folding and deploying processes of the double ring truss mechanism were simulated, and the deployable feature of the whole truss was verified.