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Abstract Architected Instability-based Metamaterials (AIMs) composed of curved beams can exhibit multi-stable geometric phase transformations. By tailoring geometry and topology, AIMs can accommodate large reversible deformations while dissipating energy beyond the capabilities of conventional materials. These exceptional mechanical properties are attractive for aerospace engineering applications, including energy-absorbing components in landing gears, impact-resistant protective structures, and vibration-damping systems. Nevertheless, this very mechanism that enables reversible energy dissipation also limits its capacity, because geometric phase transformations like snap-through buckling occur at low specific strength. Thus, the reversible energy dissipation capability cannot be easily leveraged in aerospace applications. In this work, we propose a theoretical and numerical modeling integrated approach to manipulate the out-of-plane stiffness distribution of curved beams. Compared to the conventional AIMs with uniform curved beams, the strength of the proposed beam configuration can be largely improved, while the local maximum strain remained relatively lower during phase transformations. Finite element analysis and experiments show this approach mitigates the local strain concentration effects of AIMs. Without inducing unreversible plastic deformation, the mechanical properties like the maximum peak strength, trapped energy during compression, and energy dissipation under cyclic loading can be increased by 62.1%, 82.5%, and 45.6%, respectively.
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Deployable Structures Based on Buckling of Curved Beams Upon a Rotational Input
Abstract Inspired by the recent success of buckling‐induced reconfigurable structures, a new class of deployable systems that harness buckling of curved beams upon a rotational input is proposed. First, experimental and numerical methods are combined to investigate the influence of the beam's geometric parameters on its non‐linear response. Then, it is shown that a wide range of deployable architectures can be realized by combining curved beams. Finally, the proposed principles are used to build deployable furniture such as tables and lamp shades that are flat/compact for transportation and storage, require simple or no assembly, and can be expanded by applying a simple rotational input.
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- Award ID(s):
- 1922321
- PAR ID:
- 10450164
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 31
- Issue:
- 35
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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