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ABSTRACT Modern engineering systems increasingly operate under varying vibrational environments, necessitating structural components capable of adapting their dynamic responses on demand. While springs have long served as the core of vibration control systems, their fixed stiffness fundamentally limits adaptability. Here, we introduce reconfigurable springs based on the structural instability of rod origami (RodOri), constructed from pre‐stressed, naturally curved elastic rods. By tailoring the natural curvature and cross‐sectional aspect ratio of the constituent rods, both the onset of snap‐through buckling and the post‐buckling response of individual RodOri springs can be systematically programmed. Leveraging this geometric programmability, we establish a system‐level design principle in which multiple RodOri springs of identical length but distinct buckling behaviors are assembled into a multistable metamaterial. Differences in snapping displacements enable stepwise structural reconfiguration via sequential snap‐through transitions, while variations in post‐snapping stiffness govern the mechanical response of each configuration. This hierarchical tunability enables both broad and fine control of resonance frequencies and dynamic responses across stable states. Numerical simulations and experiments demonstrate on‐demand modulation of vibration amplification, isolation, and impact mitigation within a single metamaterial, establishing RodOri springs as reconfigurable, programmable building blocks for adaptive structural and wave dynamics.
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This content will become publicly available on May 8, 2027
Elastic rod origami (RodOri) for programming static and dynamic mechanical properties
Reconfigurable mechanical systems enable precise programmable control over structural properties, expanding opportunities in architected materials, adaptive devices, and multifunctional structures. Here, we introduce elastic rod origami (RodOri), a platform that exploits remarkably simple elements—prestressed, naturally curved rods—into a system with an extraordinary degree of multistability and configurational richness. For example, a single six-rod RodOri unit can easily access 11 distinct configurations, far exceeding the reconfigurability of conventional origami or general mechanical reconfigurable systems. Individual rods, constrained under clamped boundary conditions, undergo transitions between discrete morphologies whose strain energy and stiffness are precisely prescribed by their natural curvature. Assembling these rods into modular multirod architectures yields metamaterials with numerous stable configurations that can be selectively and reversibly programmed. This configurational diversity enables tunable static stiffness and nonlinear force response, thus enabling tunable dynamic behaviors such as vibration filtering, wave propagation switching, and mode conversion within a single, easily manufactured platform. By leveraging curvature-induced mechanical instability, RodOri unlocks highly programmable static and dynamic mechanical behavior, offering tailorable design strategies for reconfigurable structures, soft robotics, medical devices, and adaptive materials.
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- PAR ID:
- 10703068
- Publisher / Repository:
- AAAS
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 12
- Issue:
- 19
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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