膜材厚度偏差对充气天线反射面精度的影响

Influence of membrane thickness deviation on precision of inflatable parabolic antenna reflector

以非线性有限元逆迭代法为基础,研究膜材厚度偏差对充气天线反射面成形精度的影响。分析均匀分布及线性非均匀分布两种典型的膜材厚度偏差分布形式对充气天线反射面的影响规律和敏感度,并考虑不同充气天线反射面焦径比F/D的影响。结果表明:形面误差的分布规律与膜材厚度偏差分布形式相关;偏差均匀分布比线性非均匀分布对精度影响更大;F/D越大,厚度偏差引起的反射面形面误差越大。

Based on the nonlinear finite element inverse iteration method, the influence ot the membrane thickness deviation on the precision of an inflatable parabolic antenna reflector was studied. Two distributions patterns of a deviation of the designed and simulated membrane thickness were considered： uniform deviation and linear non- uniform deviation. Parabolic surfaces with different F/D （focal-length-to-diameter） ratios were simulated, and error analysis was conducted. The results show the following： the surface error is relative to the distribution patterns of membrane thickness deviation, uniform thickness deviations have more significant effects than linear non-uniform ones, and the larger the F/D ratio is, the greater the surface errors will be.