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arXiv · 2207.03177

Magneto-thermomechanically triggered active mechanical metamaterials -- untethered, reversible, reprogrammable transformations with shape locking

Bihui Zou·Zihe Liang·Zhiming Cui·Kai Xiao·Shuang Shao·Jaehyung Ju
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Abstract

Future active metamaterials for reconfigurable structural applications require fast, untethered, reversible, and reprogrammable (multimodal) transformability with shape locking. Herein, we aim to construct and demonstrate a magneto-thermomechanical tool that enables a single material system to transform with untethered, reversible, low-powered reprogrammable deformations and shape locking via the application of magneto-thermomechanically triggered prestress on a shape memory polymer and structural instability with asymmetric magnetic torque. We demonstrate the mutual assistance of two physics concepts - magnetic control combined with the thermomechanical behavior of shape memory polymers, without requiring new materials synthesis and high-power energy for reprogramming. Our approach can open a new path of active metamaterials, flexible yet stiff soft robots, and multimodal morphing structures, where we can design them in reversible and reprogrammable ways.

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Bihui Zou, Zihe Liang, Zhiming Cui, Kai Xiao, Shuang Shao, Jaehyung Ju. 2022-07-07. Magneto-thermomechanically triggered active mechanical metamaterials -- untethered, reversible, reprogrammable transformations with shape locking. https://doi.org/10.1002/adma.202207349

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