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Electromagnetic (EM) metamaterials with tailored properties are developed for wave manipulation, filtering, and cloaking for aerospace and defense applications. While traditional EM metamaterials exhibit fixed behaviors due to unchangeable material properties and geometries after fabrication, reconfigurable EM metamaterials allow for tunable performance through electrical/mechanical reconfiguration strategies. Traditional biasing circuit‐based electrical reconfiguration poses challenges due to complex circuit design, while motor‐driven mechanical reconfiguration can lead to bulky and tethered structures with restricted adaptability. Herein, magnetically actuated structurally reconfigurable EM metamaterials with enhanced adaptability/conformability to different geometries, showing merits of fast, reversible, and programmable shape morphing, are developed. Magnetic actuation enables metamaterial's mechanical reconfiguration between flat deployed, flat folded, curved deployed, and curved folded states for both conformal and freestanding 3D shape morphing. Locally, the EM metamaterials fold subwavelength units for tunable properties, switching between all‐pass and band‐stop behaviors upon structural reconfiguration. Globally, the structure can conform and morph to different curved surfaces. The structurally reconfigurable metamaterial also serves as a medium for customizable subwavelength units by rationally designing attached conductive patterns for varied filtering performances such as narrow‐band, dual‐band, and wide‐band filtering behaviors, illustrating the design flexibility and application versatility of the developed structurally reconfigurable EM metamaterial.
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This content will become publicly available on May 5, 2026
Strengthening Architected Instability-Based Metamaterials (AIMs)
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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- Award ID(s):
- 2343577
- PAR ID:
- 10628485
- Publisher / Repository:
- American Society of Mechanical Engineers
- Date Published:
- ISBN:
- 978-0-7918-8875-9
- Format(s):
- Medium: X
- Location:
- Houston, Texas, USA
- Sponsoring Org:
- National Science Foundation
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