Physical reconfiguration of spacecraft antennas promises to achieve on-demand performance while staying within the power constraints of space systems. Demonstrations thus far, however, have not resulted in structures compatible with the space environment as concepts have been either heavy, had low mechanical vibration frequencies, or could not be realized from space-qualified materials. This study proposes a novel physical reconfiguration concept based on stretchable mechanical metamaterials. The approach is validated through application to a frequency reconfigurable patch antenna. The antenna is realized from thin fiber reinforced polymer composites providing a dielectric support layer for a thin conductive film. Finite element simulations are used to select the metamaterial geometry and FRP layup to meet antenna requirements, in particular to maintain a Poisson's ratio of -1 over a large range of applied strains. Measurements of the prototype demonstrate a 19% frequency drop in response to a unixial tensile strain of 27.6%, comparable to theoretical predictions and competitive with the state-of-the-art. In addition, the antenna prototype is extremely lightweight, with an average density of only 0.15 g/cm~3, shows stiff behaviour with a fundamental mechanical vibration frequency of 45.9 Hz, and is manufactured from space-appropriate materials.
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