Ultra-high-precision reflectors - design concepts, structural optimization and zero-expansion composites

摘要

The developing of satellite remote sensing technology demands high precision reflectors. This paper is devoted to the development of an ultra-high precision reflector, including the structural design and optimization, and even a kind of zero-expansion composite. A novel parabolic reflector without the traditional back surface is designed, simulated and analyzed. The relationships of some key parameters(surface error and weight) with other structural parameters are obtained. As the Kevlar fabric has negative CTE (Coefficient of Thermal Expansion) and CFRP has positive CTE, a Kevlar fabric-assisted carbon fiber composite is suggested. This composite exhibits the advantage of zero-expansion in 2D plane. Further, this zero-expansion laminate has been successfully manufactured. Finally, based on the design and analysis of the zero-expansion composite with CFRP and Kevlar fabric, an ultrahigh-precision reflector is successfully designed. The results of finite element method (FEM) show that the thermal distortion of the reflector meets the requirements of remote satellite, whose working radio frequency (RF) is 600 GHz.