长条形空间反射镜镜体及其支撑结构设计

为了满足长条形空间反射镜的设计要求,从结构材料的选择、镜厚比确定、支撑方式与最佳支撑点位置的选择以及镜体轻量化等方面进行了详细的镜体结构设计。设计了一种空间反射镜柔性支撑结构,以满足温度载荷与装配误差0.05mm工况下镜体面形精度的要求。利用有限元分析软件对反射镜组件进行分析,反射镜组件在Z向1g重力、4℃温升以及0.05mm强制位移三种工况耦合作用下的面形误差峰谷值PV为20.5nm,均方根值RMS为4.75nm,优于PV值小于λ10,RMS值小于λ50的设计指标。组件一阶频率141.83Hz,满足动态刚度要求。组件分析结果表明,反射镜及其支撑结构设计合理,满足空间应用要求。

Design of Rectangular Space Mirror and its Support Structure

In order to meet the requirements of rectangular space mirror,the material selection,thickness ratio determi-nation, supporting method, the selection of the supporting point position and the lightweight structure were taken into account in the design of the mirror. A flexible support structure was proposed to keep the surface figure accuracy under temperature change load and 0.05mm installation error cases. By adopting finite element analysis software, the mirror component was analyzed. The surface figure accuracy PV of the mirror was 20.5nm and the surface figure accuracy RMS of the mirror was 4.75nm under the load cases of gravity in Z axes coupled with temperature rise of 4℃ and 0.05mm installation error,which was superior to PV and RMS. Moreover,its first order natural frequency is 141.83Hz, which meets the requirements of dynamic stiffness. Analysis results demonstrate that the design of the mirror and its support structure are effective,which can meet the demands of space applications.