Directionally sensitive active Helmholtz resonator metamaterials enabled through 3D-printing

Controlling the absorption and diffusion of sound in the audible range is an exciting field of research. Achieving miniaturized acoustic systems able to operate at audio frequencies is one of the main challenges of acoustic engineering for many practical applications. One viable approach to tackle this challenge is by using meta materials such that deep subwavelength control can be achieved. This work investigates the fabrication and experimental characterization of membrane-coupled Helmholtz resonators as directional attenuators via 3D-printing, and introduces a 3D-printed piezoelectric component to transform acoustic attenuation to electrical outputs.