Multiplicity of actuated shapes in woven fabrics with twisted Janus fibres

TL;DR

This paper explores how woven fabrics with twisted Janus fibers can exhibit multiple stable actuation shapes due to their unique twist and phase transition properties, with potential for multistable textile designs.

Contribution

It introduces the concept of multistability in woven fabrics incorporating twisted Janus fibers, highlighting the effects of mismatched coiling and phase transitions on shape stability.

Findings

Multiple stable shapes exist within a certain extension range.

Torsion develops when active fibers are closed into a ring.

Adding passive filaments stabilizes multistability.

Abstract

We investigate actuation of woven fabrics including active Janus fibres with an imposed twist, which bend in variable directions upon phase transition between isotropic and nematic state. The essential feature of textiles incorporating a pair of Janus fibres with a mismatched pitch or handedness of coiling is the existence of multiple stable shapes with different energies within a certain range of the extension coefficient. If the active fibres are closed into a ring, torsion develops to accommodate adjustment of the direction of bending. The structure is generally stabilised by adding more passive filaments, and multistability is observed also in this case.