大型挠性航天器刚柔耦合动特性分析

摘要

The mechanical model of the spacecraft equipped with the hoop truss deployable antenna was developed and its characteristic of dynamic responses in the stage of attitude adjustments are solved numerically. Firstly the FE model composed of the central platform, solar panels and deployable antenna was established and its natural frequencies and mode shapes in the unconstrained condition were calculated. By the union simulation of FEM and Adams the zero⁃order rigid⁃flexible coupling dynamic model of the spacecraft was set up, and then the model's translation and rotation angle as well as dynamic responses of solar panels and the deployable antenna in the process of attitude adjustments were given. Results show that the lower order mode shapes of the model are mainly from the antenna′s connecting link and solar panels′ deformation while the antenna′s shape is fixed. In the procedure of attitude adjustments, the spacecraft′s flexible attachments can deform elastically along with rigid motions and the vibration is rather serious. The antenna′s geometry central point keeps vibrating around the equilibrium position even though attitude adjustments are finished.%为研究装载周边桁架式可展开天线的航天器在进行姿态调整时的动态响应特性，建立了航天器动力学模型，并对姿态调整过程的动态响应进行数值求解。首先建立由可展开天线、太阳帆板和中心平台组成的整星有限元模型并求出无约束边界条件下的固有频率和振型。通过有限元模型和Adams联合仿真建立航天器零次刚柔耦合动力学模型并求得姿态调整过程整星的位移和转角以及太阳帆板和可展开天线的动态响应。结果表明：整星的低阶模态特性主要体现在太阳帆板和天线连接杆的变形上，而天线结构无变形；航天器在进行姿态调整时，挠性部件在做大范围整体运动的同时发生显著的结构振动；航天器完成姿态调整后天线几何中心点在平衡位置附近继续振荡。