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arXiv · 2206.00153

Modelling planar kirigami metamaterials as generalized elastic continua

Yue Zheng·Imtiar Niloy·Ian Tobasco·Paolo Celli·Paul Plucinsky
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Abstract

Kirigami metamaterials dramatically change their shape through a coordinated motion of nearly rigid panels and flexible slits. Here, we study a model system for mechanism-based planar kirigami featuring periodic patterns of quadrilateral panels and rhombi slits, with the goal of predicting their engineering scale response to a broad range of loads. We develop a generalized continuum model based on the kirigami's effective (cell-averaged) nonlinear deformation, along with its slit actuation and gradients thereof. The model accounts for three sources of elasticity: a strong preference for the effective fields to match those of a local mechanism, inter-panel stresses arising from gradients in slit actuation, and distributed hinge bending. We provide a finite-element formulation of this model and implement it using the commercial software Abaqus. Simulations of the model agree quantitatively with experiments across designs and loading conditions.

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Yue Zheng, Imtiar Niloy, Ian Tobasco, Paolo Celli, Paul Plucinsky. 2022-05-31. Modelling planar kirigami metamaterials as generalized elastic continua. https://doi.org/10.1098/rspa.2022.0665

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