Tailoring reflected and diffracted wave fields from tessellated acoustic arrays by origami folding

Recently the physical reconfigurations of origami-inspired acoustic arrays have been leveraged for adaptive guidance of acoustic wave energy. The spatial translations and rotations of transducer elements in tessellated arrays may tailor how reflected and diffracted waves contribute to the total acoustic pressure at the field point. To date such wave phenomena have not been illuminated, which inhibits understanding on how to best leverage the concept for highly reconfigurable arrays. Here, the reflection and diffraction phenomena induced from a Miura-ori based acoustic array are examined, wherein such wave fields superpose with directly radiated waves to yield the total acoustic response at receiving locations. As tessellated arrays take on highly folded configurations, reflected waves are shown to greatly contribute to the acoustic field at points normal to the plane of the unfolded array, whereas diffracted waves primarily govern the acoustic pressure for locations at nearly grazing angles of incidence to the unfolded array plane. Supported by experimental validation, the modeling methods established here can be extended to arbitrary wave-radiating architectures and may inspire investigations for other physical domains where reconfigurable array concepts are of great interest.