Tensional twist-folding of sheets into multilayered scrolled yarns

TL;DR

This paper investigates how twisting hyperelastic sheets leads to the formation of multilayered self-scrolled yarns, combining elasticity, origami principles, and geometric modeling to understand and generate these complex structures.

Contribution

It introduces a new framework combining nonlinear elasticity and origami to explain and predict the formation of self-scrolled yarns from stretchable sheets.

Findings

Twisted sheets form multilayered self-scrolled yarns through recursive folding.

The model accurately predicts torque and energetics of the structures.

Algorithmic generation of structures using Schl"afli symbols is demonstrated.

Abstract

Twisting sheets as a strategy to form functional yarns relies on millennia of human practice in making catguts and fabric wearables, but still lacks overarching principles to guide their intricate architectures. We show that twisted hyperelastic sheets form multilayered self-scrolled yarns, through recursive folding and twist localization, that can be reconfigured and redeployed. We combine weakly nonlinear elasticity and origami to explain the observed ordered progression beyond the realm of perturbative models. Incorporating dominant stretching modes with folding kinematics, we explain the measured torque and energetics originating from geometric nonlinearities due to large displacements. Complementarily, we show that the resulting structures can be algorithmically generated using Schl\"afli symbols for star-shaped polygons. A geometric model is then introduced to explain the formation and structure of self-scrolled yarns. Our tensional twist-folding framework shows that origami can be harnessed to understand the transformation of stretchable sheets into self-assembled architectures with a simple twist.