Low-cost, low frequency slotted cylinder transducer

Period of Performance: 02/11/2009 - 08/11/2010


Phase 2 STTR

Recipient Firm

Etrema Products, Inc.
2500 North Loop Drive
Ames, IA 50010
Principal Investigator
Firm POC

Research Institution

Pennsylvania State University
110 Technology Center Building
University Park, PA 16802
Institution POC


In the Phase I effort a Galfenol-based slotted cylinder projector (SCP) device was conceived utilizing an existing PZT SCP design and analytical modeling to determine the geometry requirements necessary to achieve the performance specs: 210 dB source level, 750 Hz resonance frequency, 200 Hz bandwidth. The final form factor was a Galfenol SCP with overall dimensions of 7.75 diameter x 12 length utilizing a graphite composite shell material with Galfenol drivers comprising a rib-like structure within the shell. The technical objectives in Phase II will include design optimization through improved modeling efforts, the development of manufacturing processes capable of producing the Galfenol rib structures, and the construction and testing of one complete transducer system. Device test data will be compared to predicted performance results via the developed model. A design iteration will be completed on paper along with beginning investigations into reducing manufacturing costs.