Active design of chiral cell structures that undergo complex deformation under uniaxial loads

Abstract

Chiral cell structures have the potential to transform the robot design field because of the structures’ ability to adopt various deformations under uniaxial load, such as twisting and a negative Poisson’s ratio. The rationale that underpins this potential is asymmetric deformation that is similar to shearing; such a deformation has vector characteristics. In this paper, several cellular structures were designed that deformed the cell structure in many ways under uniaxial load, in accordance with the deformation vector addition principle of chiral cells (such as compression–dislocation, compression–bending coupling deformation, and variable wings with forward and backward sweep functions)—which were verified by finite-element analyses and experiments. With a given objective deformation, a genetic algorithm was introduced to encode structures with various chiral cells, and the feasibility of the method was verified through several examples. The research herein shows that structures with various deformation demands can be designed through reasonable assembly of chiral cells, which has potential applications to the field of variant structures design.