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New Sensor Finds Leaks in Spacecraft

Posted by ScuttleMonkey on from the comes-complete-with-finger-to-plug-the-hole dept.

Roland Piquepaille writes "With financial support from NASA, Iowa State University (ISU) engineers have developed a sensor to quickly find leaks in a spacecraft. This sensor locates an air leak by listening to the noise generated by the air rushing out of the leak and includes an array of 64 elements that detects vibrations as they radiate along the spacecraft. Because astronauts cannot hear the noise caused by escaping air, NASA needed to design a system to help them. As one ISU researcher said, 'NASA wants to be able to find these leaks. Fixing them is easy. But the question is, "Where is the leak?"' Now that this sensor has successfully been tested on the ground, NASA is evaluating a proposal to build a prototype of the leak detection system for future missions.

4 of 115 comments (clear)

  1. Another application. by GreggBz · · Score: 4, Funny

    It's also good for "who farted."

  2. If it find leaks... by Dr.+Spork · · Score: 4, Funny

    First customer: Steve Jobs

  3. KISS by Tank · · Score: 5, Funny

    I love tech as much as the next guy, but why not keep it simple... Submerge the craft in water, and look for bubbles. :D

  4. A few clarifications by Anonymous Coward · · Score: 5, Informative

    As one of the principal developers of this technique, I can clarify a few points:

    1. 99% of the leak noise escapes into the vacuum on the downstream side of the leak. Thus conventional industrial leak detection devices are much less effective for leaks into vacuum than for leaks into air.

    2. The real challenge is the extraction of the leak noise from other noise sources. We do this by recording cross-correlations of noise measured at different locations. Electronic (preamp) noise does not correlate and is rejected. Thus we can get far higher sensitivity than a single sensor.

    3. This device uses a piezo sensor with an array of multiplexed electrodes to sense the direction of sound propagation under the sensor. A 3D time-x-y Fourier transform maps the measured correlations from the time/space domain to the frequency/wavevector domain. The wavevector points precisely away from the leak, allowing us to find the leak through triangulation from two or more sensor arrays.

    4. For all you Linux fans, this sensor was developed entirely using open-source software. We used Linux with gEDA schematic capture and pcb.sourceforge.net for board layout. Lab measurements are done using the soon-to-be-published open-source Dataguzzler software on Linux x64.

    (Contact me for more information about Dataguzzler)

    5. One paper on this sensor, published in the journal Ultrasonics, vol 45 (2006) pp 121-126,
    can be found at http://thermal.cnde.iastate.edu/~sdh4/home/leakarray.pdf

              Stephen D. Holland
              Assistant Professor, Iowa State University