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An ultrasonic array sensor for spacecraft leak direction finding.

Stephen D Holland·Ron Roberts·D E Chimenti·Jun Ho Song
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Abstract

We have developed an ultrasonic array sensor useable for locating air leaks in manned spacecraft and have found that this sensor locates leaks in a 1-m(2) plate to within 2 cm. The sensor consists of a 63-element multiplexed array plus a reference element, all constructed from a single PZT disc and a printed circuit board. Cross-correlations of signals from the array elements with signals from the single reference element provide a measurement of the leak noise passing through the spacecraft skin under the array. A spatial Fourier transform reveals the dominant direction of propagation. Triangulation from multiple sensor locations can be used to find the source of the leak.

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Equipment DesignEquipment Failure AnalysisReproducibility of ResultsSensitivity and SpecificitySignal Processing, Computer-AssistedSpacecraftTransducersUltrasonicsEvaluation StudyJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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Stephen D Holland, Ron Roberts, D E Chimenti, Jun Ho Song. 2006-08-17. An ultrasonic array sensor for spacecraft leak direction finding.. https://doi.org/10.1016/j.ultras.2006.07.020

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