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arXiv · 2507.00996

Beyond von Mises Truss Models: Emergent Bistability in Mechanical Metamaterials

Md Nahid Hasan·Taylor E. Greenwood·Sharat Paul·Bolei Deng·Qihan Liu·Yong Lin Kong·Pai Wang
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Abstract

We observe and analyze the phenomenon of bistability emergent from cooperative stiffening in hyper-elastic metamaterials. Using experimental and numerical results of identical geometric designs, we show evidence that a single unit is unistable while combining two units can result in bistability. Our study demonstrates that the von Mises truss model cannot describe such emergent behavior. Hence, we construct a novel and simple analytical model to explain this phenomenon.

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Md Nahid Hasan, Taylor E. Greenwood, Sharat Paul, Bolei Deng, Qihan Liu, Yong Lin Kong, Pai Wang. 2025-07-01. Beyond von Mises Truss Models: Emergent Bistability in Mechanical Metamaterials. https://arxiv.org/abs/2507.00996

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