Design of primary mirror supporting structure and lightweight of space camera

In order to satisfy the strict requirements of the surface-shapes and lightweight ratios for space mirrors, the following factors for primary mirror and its support are summarized, shape decision, material selection, lightweight methods, support pattern, weight-loss function and thermal stability, according to the special requirement about primary mirror in modern space camera. The design method of lightweight structure and the flexible supporting structure of the primary mirror is proposed. In order to ensure its optical performance, flexible support structure was introduced to improve stress distribution in a variety of conditions. The finite element models for some kinds of lightweight mirror are built for analyzing the influence of the mirror weight on its surface. It satisfy that [PV]<=lambda/10, [RMS] <=lambda/40, (lambda=632.8nm) with different gravity orientation. The primary mirror structure of the dynamic stiffness was checked by modal analysis of the primary mirror. Finally, according to the experiments, It is proved that the weight, stiffness and surface accuracy of the primary mirror can meet the engineering requirement, and the mirror supporting structure and lightweight is reasonable.