空间站梦天实验舱整器动力学分析和试验研究

Dynamic Analysis and Tests for Mengtian Lab Module

空间站研制过程中,获取准确的航天器主要动力学特性有重要意义,整器动力学特性测试是研制过程中一项必不可少的大型试验项目。针对空间站梦天实验舱整器动力学问题,通过建立螺栓—法兰局部连接结构的有限元模型,分析接触状态下刚度随外力的变化关系,分别计算拉压特性下的刚度量级,并采用子结构综合方法,依据部件级模态测试结果得到梦天实验舱整器的动力学特性。结果表明:将螺栓法兰连接刚度等效为双线性弹簧,结合子结构综合预示方法,梦天整器动力学特性的预示具有较高精度。通过连接结构的精细化建模和子结构综合预示,只需进行舱段级模态试验,节省了研制经费、缩短了研制周期,可为空间站及其他大型航天器的研制提供指导。

During the space station development,it is of great significance to obtain accurate dynamic characteristics of the Mengtian lab module,and the dynamic test of the whole spacecraft is an essential large-scale test project.Aiming at the analysis of the dynamic characteristics of the Mengtian lab module,a finite element model of the bolt-flange local connection structure is established,and the relationship between the structural stiffness and the external force is analyzed.The substructure synthesis method was adopted to obtain the main dynamic characteristics of the Mengtian lab module based on the component-level modal test results.The results show that the dynamic characteristics can be predicted accurately when the bolt-flange is equivalent to a bilinear spring.So,through the fine modeling of the connection structure and the substructure method,only the module level modal test is needed for prediction of the dynamics of large spacecraft,which saves the development cost and shorts the development cycle.This practice can provide guidance for the development of space station and other large spacecraft.