Multimodal Loudspeaker Based on a Dielectric Elastomer Roll Actuator

A novel loudspeaker design integrating lightweight and efficient acoustic transducers derived from dielectric elastomer films is presented. This innovation centers on core-free dielectric elastomer roll actuators, functioning akin to artificial muscles, altering shape upon the application of an electric field. The actuators serve two roles: propelling acoustically radiating surfaces and emitting sound themselves. The paper provides a model that describes the axial vibration behavior via electromechanical and acoustic networks, facilitating understanding and comparability with electrodynamic loudspeaker systems without the need for extensive background knowledge of dielectric elastomer technology. Based on established methodologies, the design process and adaptability to diverse applications is evident. A demonstrator developed as a proof of concept with the aim of creating a broadband speaker for speech reproduction was designed, constructed, and examined utilizing the established methodology. It shows promising practicality and, in certain aspects, technological superiority over electrodynamic counterparts. Notable features, such as increased efficiency, significant weight reduction, and wide radiation pattern make this speaker viable and particularly attractive for mobile PA applications such as those found in trains and aircraft. Furthermore, the underlying principle and modeling framework allow the future creation and adaptation to a broad spectrum of applications, promising further innovation in the field.