PZT Based Low-Cost Acoustic Vector Sensors

Printed Circuits Corp, with the assistance of the Georgia Institute of Technology’s School of Mechanical Engineering, will investigate the current state of piezoelectric transduction materials, focusing on the performance and cost differences between various formulations of traditional PZTs (for example, Type 5 and Type 8) and PMN-PT “single crystal” relaxor ferroelectric materials. A study of the acoustic environments in which those potential customers would use a next generation system will provide performance boundaries for the acoustic sensor and guide a design that will dictate the material, most likely PZT, and its geometric specifications which also determine overall performance. Three potential deployment packages will be analyzed since they will appeal to different transition customers based on their specific needs. These options will include a surface-moored linear array, a bottom-moored linear array, and a towed array. The proposed next generation of vector sensors would be an excellent match for any of these deployment schemes and the adaptability of the design will provide a great advantage in allowing tailoring sensor to meet specific needs without significant redesign and production retooling. Prior vector sensor constructions use a metallic housing to protect the sensing elements from both sea water and the pressure that accompanies submergence. Phase I will analyze the possibility of using other materials, namely polymers and plastics, to provide a pressure housing that significantly reduces cost through both the material cost and the fabrication costs. The use of plastics also would change some of the design issues, namely buoyancy, which are of great importance in the performance of a vector sensor. A study will be conducted on the options that are available and how they might be mated to the assortment of customer needs. Additionally, the option for making disposable sensor arrays becomes far more viable with the significant cost reductions associated with polymer housings. Finally, Phase I will investigate different signal conditioning schemes as well as the possibility of incorporating Open Architecture Telemetry in the design of vector sensors.