Structural Design of Carbon Fiber-reinforced Plastics Barrel for Space Remote Sensing Camera

In this paper, a connecting barrel for space camera of Carbon Fiber-Reinforced Plastics (CFRP) is designed. Based on tolerance distribution in optics and composite lamination theory, the in-plane stiffness and thermal expansion coefficients due to lamination are analyzed, with structure optimized. Position error between primary and secondary mirrors, as well as modal distribution of the connecting barrel under gravity and temperature change are analyzed by finite element software. Finally, molding and fine tooling of the CFRP barrel is carried out, followed by optical inspection of the mirror system and appraisal mechanical test on the assembled camera. The analysis results show that the optical design and structural stability are satisfied by facts of 1) <0.002 mm eccentricity and <2 '' tilt achieved on the secondary mirror under lg gravity load and 2 degrees C temperature rise coupling; 2) 265 Hz fundamental frequency on the connecting barrel and on the secondary mirror combination system. Optical and mechanical performance tests show that the wavefront error of the primary and secondary mirror system meets the assembly requirements, and the barrel can bear the mechanical test of qualification level. The dual-terminal response of the barrel is amplified 1.7 times only, demonstrating desired damping property. The proposed barrel is merely 6.4 kg, which realizes light weight and high rigidity, thus satisfying the position accuracy and stability requirements on the primary and secondary mirrors for space cameras.