离轴空间遥感器主支撑结构设计

Design of main support of off-axis space remote sensor

长焦距离轴三反(TMA)空间光学遥感器各光学元件的位置精度和动态稳定性与其主支撑结构相关,因此,本文研究了遥感器主支撑结构设计方案。对比分析了主支撑结构的常用形式,确定了桁架结构方案,并对其进行了材料选择和连接工艺分析。推导了三杆结构(桁架基本单元)的一阶频率解析式,并确定了其最佳形式。在初始设计的基础上,利用灵敏度分析和参数优化设计方法得到了一种24杆式主支撑结构。作为验证,对该支撑结构进行了静态翻转和动力学试验。试验结果表明,主支撑由竖直状态翻转到水平状态后,前端倾角变化小于10″,一阶固有频率为55Hz,振动试验中支杆最大应力为135MPa,满足各项设计指标要求。

The position precision and dynamic stability of optical elements for an offaxis Threemirror Anastigmatic （TMA） space remote sensor are dependent on its main support structure, therefore, this paper researches the design scheme of the main support structure for the TMA space remote sen sor. After analysis of the common forms of main support structure, a composing of truss support structure was determined, and its materials and connection technique were discussed. The analytical solution for the first order natural frequency of the structure with three struts was derived and the best one was selected. On the basis of a original design, the sensitivity analysis and parameter optimi zation were used to obtain a main support structure with 24 struts, then it was verified by the static reversal and a dynamic test. Test results show that the front rotation angle change of the main sup port structure is less than 10＂and the first order natural frequency is 55 Hz, when it flips from a verti cal state to a horizontal state. Furthermore, the maximum stress of the main support structure is 135MPa during dynamic tests, which meets the design requirements of all indexes.