Space-reconfigurable reflector with auxetic lattice material

Abstract

A mechanically reconfigurable reflector (MRR) can adapt its geometry to facilitate a space antenna's ability to scan along different angles. The reflector geometries corresponding to various scanning angles are calculated by coordinate change. The proper mechanical properties of the MRR are important for reconfiguration accuracy and actuation of the reflector system. The ratio of bending stiffness to Young's modulus (D/E) is an essential parameter for the smooth reshaping of the MRR. In previous MMR research, materials with a small Young's modulus were used, and the D/E ratio is increased by increasing shell thickness. In order to increase the D/E ratio while maintaining a thinner shell thickness, this paper proposes an auxetic lattice material for a reconfigurable reflector shell. The auxetic lattice material allows the raw material of the reflector shell to have a high Young's modulus resulting in a smaller thickness. By optimizing the stacking sequence of carbon fiber composite, the bending stiffness of raw material is improved. Compounding the stacking sequence with elliptic voids array structure in reflector shell, the in-plane effective Young's modulus is significantly decreased while maintaining a small decrease in bending stiffness. For a given target shape, the geometric parameters of the elliptic void are determined by the comparison of the reshaping accuracy calculated through simulation.