Thin, low frequency, high displacement actuator panels

 An advanced type of thin, high displacement, low frequency actuator panel is being developed for in-air active vibro-acoustic control applications. The 10 cm×10 cm actuator panel consists of cymbal-type flextensional sub-elements placed mechanically and electrically in parallel with each other between two stiff cover plates. The total thickness of the actuator panel is 6.35 mm. Two panel designs are currently under investigation. One consists of sixty-four 12.7 mm diameter cymbals in an 8×8 square arrangement. It is intended for use in the frequency band from 1 kHz to 10 kHz. The other panel has sixteen 25.4 mm diameter elements in a 4×4 square configuration and is designed for use below 1 kHz. Laser Doppler velocimetry (LDV) measurements show peak displacements on the order of 1 μm or more are obtained when driving the panels at one Volt at their respective resonance frequencies. Received: 21 July 1998 / Reviewed and accepted: 22 October 1998