A passively tunable non-resonant acoustic metamaterial lens for selective ultrasonic excitation

Abstract

In this paper, we present an approach to ultrasonic beam-forming and beam-steering in structures based on the concept of embedded non-resonant acoustic metamaterial lenses. The lens design exploits the principle of acoustic drop-channel which enables the dynamic coupling of multiple ultrasonic waveguides at selected frequencies. In contrast with currently available technology, the embedded lens allows generating directional excitation by means of a single ultrasonic transducer. The lens design and performance are numerically investigated by using Plane Wave Expansion and Finite Difference Time Domain techniques applied to bulk structures. Then, the design is experimentally validated on a thin aluminum plate where the lens is implemented by through-holes. The dynamic response of the embedded lens is estimated by reconstructing, via Laser Vibrometry, the velocity field induced by a piezoelectric shaker source.

References in corpus (1)

• Achieving Selective Damage Interrogation and Sub-Wavelength Resolution in Thin Plates with Embedded Metamaterial Acoustic Lenses

Cited by in corpus (4)

• Design and Experimental Observation of Valley-Hall Edge States in Diatomic-Graphene-like Elastic Waveguides
• Phononic Thin Plates with Embedded Acoustic Black Holes
• Experimental evidence of robust acoustic valley Hall edge states in a non-resonant topological elastic waveguide
• Reduced order derivation of the two-dimensional band structure of a mixed-mode resonator array