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Recent studies have exemplified the potential for curved origami-inspired acoustic arrays to focus waves. Yet, reconfigurable structures that adopt curvatures are often difficult to translate to practice due to mechanical deformation of the facets that inhibit straightforward folding. In addition, not all tessellations that curve upon folding are also flat-foldable, which is a key advantage of portability inherent to many origami-inspired structures. This research introduces a new concept of partially activated reconfigurable acoustic arrays as a means to mitigate these drawbacks. Here, tessellations are studied where a subset of the facet surfaces are considered to radiate acoustic waves. The analytical results reveal focusing behaviors in such arrays that are otherwise not manifest for the array when fully activated. The focused waves are more intense in amplitude and space for partially activated arrays than fully activated counterparts. These trends are verified by experiment and are also found to be applicable to multiple reconfigurable array geometries. The results encourage broader study of the design space accessible in reconfigurable arrays to capitalize on all of the functionality afforded by origami-inspired wave guiding structures.
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Acoustic wave focusing by doubly curved origami-inspired arrays
Spherically focused transducers have been long relied on to target acoustic energy delivery. Yet, these structures have limitations with respect to size and mobility for medical treatment applications. Recent developments in the field of reconfigurable structures reveal that the ancient art of origami inspires new platforms by which to enable spherical shapes that are additionally foldable for ease of transport. This research explores the opportunities for a unique, flat foldable doubly curved tessellated array to enable wave focusing capability similar to an ideal medical transducer shape: the spherical cap transducer. An analytical model of the doubly curved array is created and validated against data collected from a proof-of-concept array. The model is then leveraged to understand how the array design and complexity relatively govern the wave focusing capability. The findings show that doubly curved acoustic arrays do not require excessive facet refinement to achieve wave focusing similar to nominal spherically focused transducers. Yet, the optimal frequencies for which such capability is borne out vary substantially on the basis of array design. The discoveries of this research motivate future consideration of flat foldable doubly curved acoustic arrays for potential implementation into medical transducer development for hard-to-access surgical treatments.
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- Award ID(s):
- 1749699
- PAR ID:
- 10548954
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Journal of Intelligent Material Systems and Structures
- Volume:
- 31
- Issue:
- 8
- ISSN:
- 1045-389X
- Format(s):
- Medium: X Size: p. 1041-1052
- Size(s):
- p. 1041-1052
- Sponsoring Org:
- National Science Foundation
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