Programmable Truncated Cuboctahedral Origami Metastructures Actuated by Shape Memory Polymer Hinges

Over the past few decades, origami-inspired structures have attracted great attention across various engineering fields due to their unique geometric and mechanical characteristics. Additionally, combining origami structures with active materials is employed to achieve programmable mechanical properties and self-reconfigurability under external stimuli. In this work, a novel family of truncated cuboctahedral origami metastructures is proposed. These designs integrate shape memory polymers (SMPs) to actively achieve programmable mechanical properties and shape memory behavior. By utilizing SMPs for the creases and stiff materials for the panels, this approach enables deformation along the creases while enhancing the overall structural robustness. The mechanical properties and shape memory processes of these structures are investigated in detail. The proposed origami metastructures exhibit a negative Poisson's ratio and demonstrate excellent energy storage capabilities. Notably, their mechanical properties can be programmed by controlling both temperature and geometric parameters. More particularly, their Poisson's ratio can be tuned within a range of zero to -1. As a result, these truncated cuboctahedral origami metastructures hold significant potential for applications across various engineering domains, particularly in composite structures and active metamaterials.