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arXiv · 2308.03630

Curvature screening in draped mechanical metamaterial sheet

Sourav Roy·C. D. Santangelo
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Abstract

We develop a framework to understand the mechanics of metamaterial sheets on curved surfaces. Here we have constructed a continuum elastic theory of mechanical metamaterials by introducing an auxiliary, scalar gauge-like field that absorbs the strain along the soft mode and projects out the stiff ones. We propose a general form of the elastic energy of a mechanism based metamaterial sheet and specialize to the cases of dilational metamaterials and shear metamaterials conforming to positively and negatively curved substrates in the F\"{o}ppl-Von K\'{a}rm\'{a}n limit of small strains. We perform numerical simulations of these systems and obtain good agreement with our analytical predictions. This work provides a framework that can be easily extended to explore non-linear soft modes in metamaterial elasticity in future.

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Sourav Roy, C. D. Santangelo. 2023-08-07. Curvature screening in draped mechanical metamaterial sheet. https://doi.org/10.1039/d3sm01108a

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