Electroacoustic Resonators: System Identification and Stabililty

Emanuele de Bono (1) , Manuel Collet (1) , Sami Karkar (1) , Gaël Matten (2) , Hervé Lissek (3) , Thomas Laurence (3)

1 LTDS - Laboratoire de Tribologie et Dynamique des Systèmes
2 FEMTO-ST - Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174)
3 EPFL - Ecole Polytechnique Fédérale de Lausanne

An Electroacoustic Resonator consists of a loudspeaker used as a membrane resonator, through an acoustic pressure-based controlled electrical current, in order to vary its vibrating velocity in re-sponse to an exogenous sound field. This way, the loudspeaker membrane can be turned, for example, into an effectively broadband sound absorber. However, the effectiveness and stability conditions of such an active device are intrinsically dependent on the accurate knowledge of its electromechanical constituents and the whole control chain, and any mismatch might impair significantly the control performance. In this paper, we propose a new method for identifying the Thiele-Small parameters of a loudspeaker to be used as an active electroacoustic resonator through a digitally-implemented control architecture. Then, numerical and experimental investigation are undertaken to show how the application of Impedance Control laws affects the stability of the electro-mechano-acoustical system. An experimental verification of the acoustic performance of the proposed control strategy is provided, leading to concluding discussion on further developments.

Mots clés: Acoustics; Control; Impedance; Loudspeaker; Stability

Domaines: Acoustique [physics.class-ph]

Emanuele de Bono, Manuel Collet, Sami Karkar, Gaël Matten, Hervé Lissek, et al.. Electroacoustic Resonators: System Identification and Stabililty. 26th International Congress on Sound & Vibration - ICSV26, Jul 2019, Montréal, Canada. ⟨hal-02389792⟩