长条形反射镜支撑结构设计与分析

为了降低航空光电侦察设备的整体质量,减小反射镜在复杂航空环境下的面形变化,利用有限元方法对某长条形反射镜组件结构进行了优化。首先,计算轻量化反射镜所需的支撑点数量,并对支撑点的位置进行优化。接着,为了解决温度变化时组件材料线胀系数不匹配带来的热变形问题,在支撑结构中引入了柔性铰链,并对柔性铰链参数进行了优化。最后,对反射镜组件进行面形精度分析,得到反射镜RMS为20.3 nm,小于1/30(=632.8 nm);对组件进行模态分析及试验,得到一阶固有频率分别为138 Hz和162 Hz,满足设计指标要求,分析及试验结果表明了该反射镜的支撑结构合理可行。

Design and analysis of supporting structure for rectangular mirror

The rectangular mirror supporting structure was designed and optimized for reducing the weight of the aerial optical remote sensor and minishing the shape error of the mirror, which was working in the bad aerial environment. First, the supporting point number of the ligntweighted mirror was calculated and the point position was optimized. Secondly, the flexible hinge was designed and optimized in the supporting structure in terms of the thermal deformation, which was indeced by the different expansion coefficients between the mirror and the back supporting structure. Finally, the surface shape was analyzed, the RMS was 20.3 nm, less than the design requirements, 1/30(=632.8 nm), the model was analyzed and tested, the first-order natural frequence was 138 Hz and 162 Hz. The results indicate that the designed structure is resonnable and feasible.