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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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Topological wave energy harvesting in bistable lattices
Abstract In this paper, we present an input-independent energy harvesting mechanism exploiting topological solitary waves. This class of medium transforming solitons, or transition waves, entails energy radiation in the form of trailing phonons in discrete bistable lattices. We observe numerically and experimentally that the most dominant frequencies of these phonons are invariant to the input excitations as long as transition waves are generated. The phonon energy at each unit cell is clustered around a single invariant frequency, enabling input-independent resonant harvesting with conventional energy transduction mechanisms. The presented mechanism fundamentally breaks the link between the unit cell size and the metamaterial’s operating frequencies, offering a broadband solution to energy harvesting that is particularly robust for low-frequency input sources. We further investigate the effect of lattice discreteness on the energy harvesting potential, observing two performance gaps and a topological wave harvesting pass band where the potential for energy conversion increases almost monotonically. The observed frequency-invariant phonons are intrinsic to the discrete bistable lattices, enabling broadband energy harvesting to be an inherent metamaterial property.
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- Award ID(s):
- 1935137
- PAR ID:
- 10378766
- Date Published:
- Journal Name:
- Smart Materials and Structures
- Volume:
- 31
- Issue:
- 1
- ISSN:
- 0964-1726
- Page Range / eLocation ID:
- 015021
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1088/1361-665X/ac37ff
