Bioinspired Continuous 2.5D Woven Miura-ori Metasurface for Mechanically Tunable Microwave Filtering

Abstract

Rigid mechanically reconfigurable frequency-selective surfaces (FSSs) provide well-defined geometric tuning but are difficult to conform to complex curved surfaces, whereas conventional frequency-selective fabrics (FSFs) are conformable. Reported origami FSFs, however, generally use uniform textile substrates with fold lines introduced after textile fabrication, limiting direct structural guidance of Miura-ori reconfiguration. Here, we develop a bioinspired continuous 2.5D woven Miura-ori frequency-selective metasurface. Multilayer angle-interlock facet regions and single-layer plain-weave hinge regions are continuously integrated within a single aramid substrate through electronic Jacquard weaving. The facet regions support printed cross-shaped conductive units, whereas the hinge regions directly form the Miura-ori fold lines and guide the woven metasurface along the designed folding paths. These region-specific functions guide the woven metasurface along a defined Miura-ori deformation pathway, enabling monotonic folding-dependent frequency tuning over the investigated folding states. Under normal incidence, the measured resonant frequency decreases monotonically from 9.02 to 8.05 GHz as the folding angle decreases from 90° to 45°, yielding a tuning span of 0.97 GHz. At a folding angle of 60°, the resonant-frequency variation is 0.57 GHz over incidence angles from 0° to 45°, while the maximum variation among the investigated conformal configurations is 0.21 GHz. Full-wave simulations and a transmission-line equivalent circuit model with effective circuit parameters fitted using particle swarm optimization were used to interpret the folding-induced redshift. The redshift is associated with reduced projected separation between cross-shaped conductive units on adjacent facets, enhanced near-field coupling, increases in the fitted equivalent inductance and total equivalent capacitance, and additional phase accumulation represented by the calculated effective propagation-length coefficient. These results provide a textile-based strategy for mechanically tunable microwave filtering on curved surfaces.