Acoustic metamaterials are materials designed to control, direct and manipulate soundwaves as they pass through different mediums. As such, they can be designed and inserted into a structure to dampen or transmit sound.
The problem is, traditional acoustic metamaterials have complex geometries. Often made of metal or hard plastic, once they are created, they cannot be changed. Take for example, an acoustic device constructed to dampen outgoing sound in a submarine, so that it can achieve stealthiness. If a different condition arose, for instance an ally the submarine wanted to communicate with passes by, the same acoustic device would not allow for sound to be transmitted externally.
A team of USC researchers created a new smart material that accommodates shifts in acoustic transmission on demand. The team discovered that their smart material had the capability of re-creating properties intrinsic to electronic devices such as switches, thus showing promise of smart sound transmission–a sound “computer.”
Inspired by the dual properties created by the dermal denticles on the surface of a shark’s skin, the team created the new acoustic metamaterial that contains magneto-sensitive nanoparticles that will bend under the force of magnetic stimuli. This magnetic force can change the structure remotely and on-demand, accommodating different transmission conditions.
News Source: Eurekalert
