Fig. 2: Randomized resonant metamaterial system for multi-source vibration identification.
From: Randomized resonant metamaterials for single-sensor identification of elastic vibrations
a Schematic of the randomized resonant metamaterial system. b The supercell composed of 19 unit cells with different geometric parameters of spiral beams. (c) The dispersion curves of the unit cell with θ = 2.952π. The out-of-plane band gap is from 304.0 Hz to 493.7 Hz. The frequency range of the negative effective mass density is consistent with the out-of-plane band gap. The vibration modes at edges of the band gap are marked by A1 and A2. d The relationship between the local resonance frequency and the angle θ. The results calculated by the finite element method (FEM) are marked by circles, and the fitting curve is marked by the red solid line. e Spatial distribution of local resonance frequencies of the entire metamaterial.
