Broadband barrel-stave flextensional transducers

Abstract

The last time I discussed underwater transduction technologies with Joe Blue was at the 125th Meeting of the Acoustical Society of America in May 1993. As we enjoyed lunch on the patio of a downtown Ottawa bistro under a sunny spring sky, the discussion touched on broadband transducers for naval applications. His ideas were insightful, motivating me to redesign and improve my original 1989 broadband barrel-stave flextensional transducer the following year. Over the last decade 30 experimental units were built at DRDC Atlantic, most of them used in marine mammal and coastal surveillance applications [D.F. Jones, J. Acoust. Soc. Am. 117, 2447 (2005); 118, 2038–2039 (2005)]. This paper will present electroacoustic measurements made at both the DRDC Atlantic Acoustic Calibration Barge on Bedford Basin near Halifax, Nova Scotia and the NAVSEA Seneca Lake Sonar Test Facility near Dresden in upstate New York. The performance parameters of interest include resonance frequencies, mechanical quality factors, transmitting voltage response versus water depth, and directivity patterns. [Work supported in part by the Office of Naval Research.]