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arXiv · 2506.20110

Gear-based Metamaterials for Extraordinary Bandgap Tunability

Xin Fang·Jihong Wen·Dianlong Yu·Peter Gumbsch·Huajian Gao
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Abstract

Metamaterials can be engineered with tunable bandgaps to adapt to dynamic and complex environments, particularly for controlling elastic waves and vibration. However, achieving wide-range, seamless, reversible, in-situ and robust tunability remains challenging and often impractical due to limitations in bandgap mechanisms and design principles. Here, we introduce gear-based metamaterials with unprecedented bandgap tunability. Our approach leverages Taiji planetary gear systems as variable-frequency local resonators, which allows the metamaterial to seamlessly modulate its bandgap's center frequency by 3-7 times (e.g. shifting from 250-430 Hz to 1400-2000 Hz), surpassing existing methods. Notably, this is achieved without pre-deformation or major changes to its static stiffness in the wave propagation direction, ensuring robust in-situ tunability and smooth control even under heavy static loads. This enables adaptable wave manipulation for versatile smart platforms.

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Xin Fang, Jihong Wen, Dianlong Yu, Peter Gumbsch, Huajian Gao. 2025-06-25. Gear-based Metamaterials for Extraordinary Bandgap Tunability. https://arxiv.org/abs/2506.20110

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