Design and validation of locally resonant metaplate with tunable bandgaps for inertial sensors

Abstract The design, optimization, and experimental characterization of a tapered lamina emergent torsional (LET) spring architecture-based metaplate are presented. The metaplate is engineered to achieve a low-frequency, broadband elastic bandgap for noise and vibration isolation within a compact, monolithic unit cell. Transmission of elastic waves is passively suppressed in both in-plane and out-of-plane directions, enabling three-dimensional wave attenuation in a planar structure. A prototype metaplate is fabricated using single-material 3D printing for experimental validation. Experimental results demonstrate attenuation levels of approximately − 40 dB for out-of-plane excitation and − 20 dB for in-plane excitation. The bandgap is also experimentally tuned to exhibit a relative bandgap width of approximately 48% in the sub-kHz range. This approach provides an alternative to traditional locally resonant or multilayered metamaterial platforms by validating a planar LET-based bandgap mechanism at the millimetre scale. The resulting geometry framework can be adapted for future microscale implementations.