title: An ultrasonic array sensor for spacecraft leak direction finding.
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.
authors.affiliation: Center for Nondestructive Evaluation, Iowa State University, Ames, IA 50011, USA. sdh4@iastate.edu <sdh4@iastate.edu>
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Holland
authors.forename: Ron
authors.initials: R
authors.lastname: Roberts
authors.forename: D E
authors.initials: DE
authors.lastname: Chimenti
authors.forename: Jun Ho
authors.initials: JH
authors.lastname: Song
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D018531:Spacecraft; D014159:Transducers; D014465:Ultrasonics