Novel rotational motion actuated beam-type multistable metastructures

This work aims to explore and design a family of multistable metastructures, which are actuated by rotational motion. The bi-stability design criteria for a single pre-shaped beam unit are studied firstly using an analytical model and finite element method. Based on this bi-stability study, a typical one-layer of this novel rotational motion actuated bistable structure, which is composed of four pre-shaped beams assembled uniformly inside two circular frames, is proposed and fabricated. The mechanical behaviour of this bistable structure represented in terms of moment-angle curves are analyzed by the finite element method and experiments. A parametric analysis is performed to study the influence of geometric parameters of an one-layer multistable metastructure on its bi-stability performance, which provides the guidance to design multistable structures with more layers. Lastly, multistable structures with two layers and three layers, which can achieve large rotations with controllable angle-step and snapping sequence, are designed and studied. Furthermore, this research demonstrates other as-fabricated beams with bistability have prospects to design the rotational multistable metastructures. The multistable metastructures proposed in this work create new opportunities to design advanced reconfigurable structures and devices. (c) 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).

Automated summary

This study aims to explore and design a family of multistable metastructures that are actuated by rotational motion. The bi-stability design criteria are studied using an analytical model and finite element method. Based on this study, one-layer, two-layer, and three-layer multistable structures are designed and analyzed, demonstrating their potential for reconfigurable applications.