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Underwater Explosion Sensor Data Collection



OBJECTIVE: The objective of this STTR is to develop a method to make environmental data from underwater explosions (UNDEX) available to medical professionals to help with injury treatment. To meet this objective, a conductive fiber (e-textile) suitable for detecting shock waves, including on-board data recording capabilities, will be developed. Recorded e-textile data will be formatted to allow integration with other sensor technologies. Development of the e-textile will make UNDEX exposure data available to medical professionals, which is expected to improve injury outcomes. 

DESCRIPTION: Recent investigations into piezoelectric fibers have resulted in the development of fibers capable of converting mechanical vibrations into electrical signals, allowing these fibers to ‘hear’ [1]. The Department of Defense is already actively involved in this area of research, and has a participating membership in the Advanced Functional Fabrics of America (AFFOA) research initiative [2, 3]. The focus of this STTR is to identify fibers that can operate in both fresh and salt water and detect vibrations associated with the shock wave of an UNDEX. The fibers must be able to be woven into an e-textile uniform or strap (the actual weaving is outside the scope of this STTR). These fibers will provide medically relevant data to improve diagnosis and treatment determinations from injuries resulting from UNDEX. The fibers may also be used to detect physiological measures of warfighter stress, such as respiration rate, heart rate, and other indicators. The e-textiles developed by this STTR will find use by operators in aquatic environments. Early adopters of the products from this STTR may include surface and undersea warfare operators, first responders, and undersea construction and salvage crews. Utilization of the e-textiles will allow monitoring for potential injuries and logging of relevant exposure characteristics, which will improve operational safety. 

PHASE I: In Phase I, the vibration detection characteristics of different fibers will be evaluated. Researchers will identify piezoelectric fibers that can operate in water. Selected fibers will be required to reliably detect the frequency and amplitude of UNDEX shock waves, while meeting or exceeding the strength of traditional textiles. These requirements will apply for both dry and wet environments. The fibers will be required to possess similar durability to normal textiles for UNDEX exposures. Researchers may identify multiple fiber technologies capable of detecting shock waves. 

PHASE II: In Phase II, a prototype electronics package will be constructed and tested both in air and while submerged. This prototype will include vibration detecting fibers, a processor, and digital data storage capability. Prototypes will utilize the candidate fibers identified during Phase I to determine which fibers are best suited for detecting medically relevant UNDEX shock wave characteristics. A test fixture will be constructed to record electrical signals generated by the submerged conductive fiber in response to shock waves. The test fixture will be subjected to the sounds expected from a warfighter and to shock waves representative of UNDEX. The test fixture will be used to measure any possible degradation of signal detection following exposure to an emulated UNDEX. Prototypes will be evaluated based on detection of UNDEX characteristics and physiological measures of warfighter stress. Additionally, prototypes may possess the ability to detect other sounds relevant to warfighter safety, such as splashing, coughing, or calling for help. Researchers will use shock waves that emulate UNDEX, and the sponsor may opt to conduct additional tests using more realistic sources. To enable realistic exposures, the prototype should be ruggedized sufficiently to withstand operationally representative shock wave amplitudes. The data collected in Phase II will be provided to the sponsor in a computable format. 

PHASE III: In Phase III, a fully submersible stand-alone conductive fiber strap (e-textile) with onboard data-recording will be constructed using the fibers selected in Phase II. Data collected from the e-textile will be extracted for post testing analysis. The e-textile will be tested in water to demonstrate an operational capability, as done with the fibers in Phase II. Completed e-textile prototypes and data will be delivered to the sponsor for further evaluation and analysis. The testing will include salt water and fresh water environments operating in cold and warm temperatures. 


1: Larry Hardesty, MIT News Office, Fibers that can hear and sing, July 12, 2010,



4:  UbiComp '13 Adjunct Proceedings of the 2013 ACM conference on Pervasive and ubiquitous computing adjunct publication Pages 207 – 210.


KEYWORDS: UNDEX (Underwater Explosion), E-textile, Piezoelectric Fiber, EHR (Electronic Health Record) 

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