iMSL – Intelligent Material Systems Lab – Lehrstuhl für intelligente Materialsysteme an der Universität des Saarlandes

A multi-domain dynamical model for cone-shaped dielectricelastomer loudspeakers

This paper presents a multi-physics model of an electrostatic loudspeaker system that combines the acoustic diaphragm and the actuator into a lightweight dielectric elastomer (DE) membrane. The focus is set on the so-called cone-shaped DE actuator (DEA) topology, which features a self-standing compact architecture, free from pneumatic loading systems, and is potentially suitable for integration onto complex surfaces and structures. We propose an axial-symmetrical lumped-parameter nonlinear model of the cone DEA structural dynamics, and use it to predict the acoustic pressure field generated by the speaker. We then present a case study in which the model is used to predict the linearised mode shapes of a reference DEA, evaluate their effect on the acoustic frequency response, and compare the harmonic distortions resulting from different driving strategies.

Giacomo Moretti,1 Gianluca Rizzello,2 Marco Fontana,3 Stefan Seelecke2

1Univ. des Saarlandes (Italy)
2Univ. des Saarlandes (Germany)
3Scuola Superiore Sant’Anna (Italy)