Mechanics of curved crease origami: 1DoF mechanisms, distributed actuation by spontaneous curvature, and cross-talk between multiple folds

TL;DR

This paper explores the mechanics of curved crease origami, focusing on one-degree-of-freedom mechanisms, actuation via spontaneous curvature, and the interactions between multiple folds, highlighting their implications for robust morphing structures.

Contribution

It introduces a comprehensive analysis of curved crease origami mechanics, comparing geometric and mechanical approaches, and examines fold cooperativity and energetic benefits of synchronous folding.

Findings

Curved crease origami can be modeled as 1DoF mechanisms.

Synchronous folding offers energetic advantages over sequential folding.

Active shell and solid mechanics approaches complement geometric models.

Abstract

Origami morphing, obtained with patches of piecewise smooth isometries separated by straight fold lines, is an exquisite art that has already received considerable attention in the mathematics and mechanics literature. Curved fold lines, leading to curved creases and curved pleated structures, introduce the additional complexity of mechanical coupling between the folds. This coupling can be exploited to obtain morphing structures with more robust folding pathways. We discuss one-degree-of-freedom mechanisms and folds actuated by spontaneous curvature (as in the case of hygromorphic multilayered composites), comparing the purely geometric approach to two approaches based on the mechanics of active shells and of active three-dimensional solids. Moreover, we discuss the cooperativity of multiple folds and demonstrate the energetic advantage of synchronous folding over sequential folding.