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arXiv · 1806.10851

Shape-morphing architected sheets with non-periodic cut patterns

Paolo Celli·Connor McMahan·Brian Ramirez·Anton Bauhofer·Christina Naify·Douglas Hofmann·Basile Audoly·Chiara Daraio
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Abstract

We investigate the out-of-plane shape morphing capability of single-material elastic sheets with architected cut patterns that result in arrays of tiles connected by flexible hinges. We demonstrate that a non-periodic cut pattern can cause a sheet to buckle into three-dimensional shapes, such as domes or patterns of wrinkles, when pulled at specific boundary points. These global buckling modes are observed in experiments and rationalized by an in-plane kinematic analysis that highlights the role of the geometric frustration arising from non-periodicity. The study focuses on elastic sheets, and is later extended to elastic-plastic materials to achieve shape retention. Our work illustrates a scalable route towards the fabrication of three-dimensional objects with nonzero Gaussian curvature from initially-flat sheets.

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Paolo Celli, Connor McMahan, Brian Ramirez, Anton Bauhofer, Christina Naify, Douglas Hofmann, Basile Audoly, Chiara Daraio. 2018-06-28. Shape-morphing architected sheets with non-periodic cut patterns. https://doi.org/10.1039/c8sm02082e

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