2024-09-24 ロイヤルメルボルン工科大学(RMIT)
＜関連情報＞
- https://www.rmit.edu.au/news/all-news/2024/sep/origami-innovation
- https://www.pnas.org/doi/10.1073/pnas.2409062121
セルフロックと剛性を備えた展開可能な管状構造体 Self-locking and stiffening deployable tubular structures
Ting-Uei Lee, Hongjia Lu, Jiaming Ma, +2, and Yi Min Xie
Proceedings of the National Academy of Sciences Published:September 27, 2024
DOI:https://doi.org/10.1073/pnas.2409062121
Significance
Origami-inspired mechanisms can transform flexible sheets into lightweight and efficient structures. Inspired by curved-crease origami, here, we design a deployable tubular structure featuring geometric self-locking and stiffening effects using simple shell components. This tube challenges the fundamental trade-off between expandability and load-bearing capacity in deployable structures. Despite its high material deformability, the deployed state provides high stiffness against external loading through internal stiffeners. These stiffeners, which bend and undergo pseudofolding, are confined during deployment. They induce elastic shell buckling and create an energy barrier that facilitates a snap-through transition. Our results demonstrate that the proposed tube opens different possibilities for improving existing deployable mechanisms and creating innovative structural designs, impacting diverse applications where deployable tubular structures are employed.
Abstract
Deployable tubular structures, designed for functional expansion, serve a wide range of applications, from flexible pipes to stiff structural elements. These structures, which transform from compact states, are crucial for creating adaptive solutions across engineering and scientific fields. A significant barrier to advancing their performance is balancing expandability with stiffness. Using compliant materials, these structures achieve more flexible transformations than those possible with rigid mechanisms. However, they typically exhibit reduced stiffness when subjected to external pressures (e.g., tube wall loading). Here, we utilize origami-inspired techniques and internal stiffeners to meet conflicting performance requirements. A self-locking mechanism is proposed, which combines the folding behavior observed in curved-crease origami and elastic shell buckling. This mechanism employs simple shell components, including internal diaphragms that undergo pseudofolding in a confined boundary condition to enable a snap-through transition. We reveal that the deployed tube is self-locked through geometrical interference, creating a braced tubular arrangement. This arrangement gives a direction-dependent structural performance, ranging from elastic response to crushing, thereby offering the potential for programmable structures. We demonstrate that our approach can advance existing deployment mechanisms (e.g., coiled and inflatable systems) and create diverse structural designs (e.g., metamaterials, adaptive structures, cantilevers, and lightweight panels).Weanticipate our design to be a starting point to drive technological advancement in real-world deployable tubular structures.
