Modeling SMA-enabled soft deployable structures for kirigami/origami reflectors

Abstract

The synergic combination of smart soft composites with kirigami/origami principles leads to self-deployable systems. To date, the development of soft deployable structures has largely been an empirical process. Focusing on the recently developed shape memory alloy (SMA)-based soft deployable structures, this paper describes an analytical model and a finite element (FE) numerical scheme to investigate deformation and deployment performance of this system. The study provides insights into the working principles of these soft deployable structures by understanding how the system deforms as a function of the SMA recovery strain for a number of geometrical parameters. The FE method was further used to simulate the fabrication and deployment process of three types of kirigami/origami reflectors. The realization of a two-step scheme, i.e., predeformation of the deployable frame and then the concurrent deformation of both frame and kirigami/origami films, is detailed herein. This makes our simulation capable of capturing the features of SMA-based soft deployable structures observed in experiments, and also renders the prediction versatile and manufacturing-oriented. We expect the work would enhance the understanding of soft deployable structures, and may open the door for design and fabrication of soft robotics and machines.