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arXiv · 2006.01589

Evolving, complex topography from combining centers of Gaussian curvature

Fan Feng·John S. Biggins·Mark Warner
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Abstract

Liquid crystal elastomers and glasses can have significant shape change determined by their director patterns. Cones deformed from circular director patterns have non-trivial Gaussian curvature localised at tips, curved interfaces, and intersections of interfaces. We employ a generalised metric compatibility condition to characterize two families of interfaces between circular director patterns -- hyperbolic and elliptical interfaces, and find that the deformed interfaces are geometrically compatible. We focus on hyperbolic interfaces to design complex topographies and non-isometric origami, including n-fold intersections, symmetric and irregular tilings. The large design space of three-fold and four-fold tiling is utilized to quantitatively inverse design an array of pixels to display target images. Taken together, our findings provide comprehensive design principles for the design of actuators, displays, and soft robotics in liquid crystal elastomers and glasses.

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Fan Feng, John S. Biggins, Mark Warner. 2020-06-02. Evolving, complex topography from combining centers of Gaussian curvature. https://doi.org/10.1103/physreve.102.013003

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