Topology Optimization for Discovery of Auxetic Origami Structures

Origami, as it moves from an art to a scientifically useful technology, enables a rich design space given the numerous bifurcations that exist off the flat state. In this work, we utilize origami as a platform for design of auxetic metamaterials and employ topology optimization for the automated robust discovery of these structures. In particular, the mechanical analysis is performed with an efficient and accurate nonlinear truss element model that captures the geometric nonlinearities associated with origami folding, and modal analysis off the flat state enables access to the many bifurcating branches of folding. Here, objective functions are explored that target a desired in-plane Poisson’s ratio. The Miura-ori fold pattern, a commonly studied flat-foldable pattern, is considered as a verification study for the framework presented.