Active elastic metamaterials with applications in acoustics

Simon Pope , Hatim Laalej , Steve Daley

Elastic metamaterials provide a new approach to solving existing problems in acoustics. They have also been associated with novel concepts such as acoustic invisibility and subwavelength imaging. To be applied to many of the proposed applications a metamaterial would need to have the desired mass density and elastic moduli over a wide frequency band. To minimise scatter in acoustics applications the impedance of solid elastic metamaterials also need to be matched to the impedance of the surrounding medium. Previous work has looked at the trade-off between achieving the desired mass density and Youngs modulus, combined with an impedance which is matched to the surrounding medium. This paper will focus on extending the bandwidth of the desired properties presented in previous work to an extent where the material could be applied to some of the novel applications. This will include a consideration of the problems which arise when the previously developed theory and simulation is developed into an experimental demonstration. This includes the role which the control system dynamics play on the achievable performance. It will also consider the problems which arise when the previous one-dimensional concept is extended to higher dimensions.

Mots clés: Metamaterial; Active control

Domaines: Acoustique [physics.class-ph]

Simon Pope, Hatim Laalej, Steve Daley. Active elastic metamaterials with applications in acoustics. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00810703⟩