They can be applied to curved surfaces, tolerating bending radii as low as 20 mm. The transducers are made by placing a piezoceramic foil between two conductive films and embedding everything in a ductile composite-polymer structure. In this way, the brittle piezoceramic is mechanically prestressed and electrically insulated. Wear and failure rates are low because the solid-state actuators contain no moving parts.

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