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Mechanical metamaterials with multiple stable configurations offer a promising avenue for the design and development of adaptable materials with unprecedented levels of control over physical properties. Specifically, arrays of bistable beam elements represent a unique metamaterial platform with tunable transition waves offering means of passive control, sensing, and memory effects of environmental conditions. Although previous studies have mainly investigated transition waves triggered by a static input in nonlinear metamaterials, the dynamic properties of these structures and the interference of colliding waves are still unknown. Here, we investigate the dynamic properties of arrays of bistable beam elements which are important keys in the further development of applications of these metastructures. We determine the critical force and the optimal location to apply a force to trigger a transition wave and characterize the natural frequencies of the metamaterial. Moreover, we study the interference between two transition waves simultaneously actuated at both ends of the one-dimensional multistable array. Our new insights on the nonlinear dynamic responses of multistable metamaterials pave the way for the ability to design and program adaptable structures with enhanced energy absorption, vibration isolation, and wave steering capabilities.
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Synthetic mechanical lattices with synthetic interactions
Metamaterials based on mechanical elements have been developed over the past decade as a powerful platform for exploring analogs of electron transport in exotic regimes that are hard to produce in real materials. In addition to enabling new physics explorations, such developments promise to advance the control over acoustic and mechanical metamaterials, and consequently to enable new capabilities for controlling the transport of sound and energy. Here, we demonstrate the building blocks of highly tunable mechanical metamaterials based on real-time measurement and feedback of modular mechanical elements. We experimentally engineer synthetic lattice Hamiltonians describing the transport of mechanical energy (phonons) in our mechanical system, with control over local site energies and loss and gain as well as over the complex hopping between oscillators, including a natural extension to nonreciprocal hopping. Beyond linear terms, we experimentally demonstrate how this measurement-based feedback approach makes it possible to independently introduce nonlinear interaction terms. Looking forward, synthetic mechanical lattices open the door to exploring phenomena related to topology, non-Hermiticity, and nonlinear dynamics in nonstandard geometries, higher dimensions, and with novel multibody interactions.
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- Award ID(s):
- 1945031
- PAR ID:
- 10501849
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review A
- Volume:
- 108
- Issue:
- 1
- ISSN:
- 2469-9926
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1103/PhysRevA.108.012221
