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New Sensor Finds Leaks in Spacecraft
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.
It's also good for "who farted."
First customer: Steve Jobs
National Aeronautics and Space Administration - Small Business Technology Transfer (STTR) Program
:)
PROPOSAL NUMBER: 06 T5.02-9832
Have a try
CC.
TaijiQuan (Huang, 5 loosenings)
I bet NASA is wishing they had this ten years ago!
.sig
The summary states that the detection system detects the sound made by air escaping. This is not true. The sound of the air escaping is OUTSIDE the spaceship (as said in the article) and therefore cannot be detected within the craft. The detection system is simply the array of vibration sensors.
What in the world do they do for human air leaks- I mean passing putrid gas on the spaceship?
Hmmmm, I have a mass of air leaking from a space ship. My detector mechanism is outside in the vacuum. I wonder how I could detect this escaping air? Maybe the detector will announce that it hears something when it passes through the mass of air? BRILLIANT!
Now where's my contract?
I'm curious what size of leak they're targetting here.
:)
I've heard an interesting suggestion for an automatic leak plugging system - floating, easily popped bags of quick drying sealent. Any leak will create air currents that will suck the bags into the holes, where they pop and seal the whole.
This of course ignores all sorts of potential problems (holes in areas obscured by cables/ductwork, for one thing) but I thought it was neat anyway
This type of survey has been used in the oil industry since the 1980's...
"noise log" leak detection
But I have to admit this is 3D against 2D.
"The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."
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
I was thinking the same thing except that it was Dr. Pepper. This is a solved problem. Hmmm, that reminds me, we need to move all biological research to space where advanced DNA modeling with M&M's can occur.
Incense.
Just follow the smoke... Good for karma and centering your Qi, too!
I have something in common with Stephen Hawking...
The telephone company (way back when there was just ONE big one, ATT), used to have like lots of copper wires running from pole to pole (way back when there were wires, and poles, and above-ground stringing).
In the wetter climates the wires were covered in a lead casing (back when lead wasn't so despised). The lead "tubes" were pressurized to keep the moisture out. If the lead sheathing got a leak, a guy (back when telephone company people in the field were guys) would walk down the street holding up an ultrasonic microphone.
A little box on his belt would map the ultrasonic frequencies down to the audible range and feed it to his headphones (back when headphones were big clunky black bakelite things).
Seriously though, I kinda hope that this is intended to be used from inside the crew cabin. Using it outside the space craft is gonna be problematic if it actually relies on the sound of the gas escaping.
When asked for comment, Buzz Aldrin said "I don't find leaks, I only take them"
I thought you were supposed to put some in space ship and check for a leak if they congregate in one place?
Well in this case the simple solution might not be the best, ;)
because you will hardly see smoke moving towards the leak,
and when you see you should run
Think of the ISS it's constructed from cylindrical elements, and you have a quadratic shaped interior, so the space gap is filled with computers (some Laptops == fan) possible cooled instrument racks which emmit heat (convection) and on the inner layer an insulation.
If your presure- and ultrasoundsensors detect such a leak you have to generate
smoke, this smoke will going to follow the airflow which is driven by presure diferences,
but you also have temperaturdifferences or forced convection nearly everywere,
even the astronauts moving will disturb the free flow extremly, and you have no
gravition which helps you to settle the turbulences fast.
The leak might be so tiny, so the volume flowing through it will not interfere with the inside
atmosphere in deep.
Finally sound is still transmitted through the material of the spacecraft itself, so monitors attached to said spacecraft would still detect sound. An example of this would be Tonto putting his ear to the ground to determine how big the posse is.
I read Slashdot for the headlines, because the headlines, unlike the articles, are usually original and never duplicated
They can't mount this sensor outside the craft pointing in, because the intervening empty space carries no sound energy.
But if they mount it internally, it could find not only leaks, but also target where that hideous alien creature is hiding after it's eaten the ship's cat.
--
make install -not war
I find leaks in my bicycle tubes with soap and water. Why don't they spray soap all over it and look for the bubbles?
Pretty sure this thing works by detecting the vibrations resonating throughout the structure of the ISS, not through the air inside it. So it'll still work, even in a vacuum.
If you build it, nerds will come. Soylentnews.org
In "Mission to Mars" they used Dr Pepper. It has an added advantage in that you can drink it if there are no leaks. This would help keep the astronauts awake, so they are more aware of air leaks. Solves multiple problems.
Vincent J. Murphy
Spandex Justice
Gil "the ARM" Hamilton doesn't have this problem.
I don't know if it's incompetence, a preexisting medical condition (like de Palma being totally nuts), or vengence on a meddling Disney corporation that is responsible for Mission to Mars. But product placement is so obvious in the movie (only a minute long informercial on the joys of M&Ms or Dr. Pepper would be more so), that I think Disney must have really ticked de Palma off. Hmmm, glancing at this interview, I see two lines really stand out:
and something de Palma says in the interview
So he gives only one interview supposedly in the US (strange thing for a director to do) and the only thing (as far as I saw) that he says about his studio backers is that they wanted it done on a tight schedule and he delivered. Also a lot of talking about "storyboarding" (laying out a series of stills ahead of time that you want in a film sequence) and how he had to follow it.
there is no air in space but the spacecraft its self can transit "sound waves" they're called vibrations. they don't need air.
Sigs are too short to say anything truly profound so read the above post instead.
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
I saw a fairly lengthy presentation on this a while back so I have a rough understanding on how it works. It's an array of accelerometers which measures the vibration of the material it's mounted on and then uses software to "triangluate" (wrong word, right idea) the direction and distance from the sensor is to where the "sound" is coming from. There isn't an exact point, more like a probability distribution with hot-spots.
The sound being picked up is not carried by air - it is the vibrations caused by the escaping air transmitted through the spacecraft itself.
Ground control to Major Tom:
Your circuit's dead,
there's something wrong.
Can you hear me Major Tom....?
otherwise there might be too much methane in the ship
Nobody can hear you leak! You need machines for that.
SPACE?
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
Unless of course the whole atmosphere was filled with tiny flakes of stuff, in which case people would be inhaling them and gooping up their airways.
Engineering is the art of compromise.
I personally know two professors who work there and they are both top-notch.
-A side note: Ames, IA was the largest producer of Uranium 235 in the world between 1940 and 1950.
At the risk of being flagged "redundant"...
So what, now I'm not *supposed* to take a leak in a spacecraft?
Other than this text, there is no discernible information contained in this sig.
This type of tech has been in use for twenty years (or more) to find leaks in coolant lines and radiators used in air conditioning systems installed in everything from homes, businesses, and vehicles.
http://buy1.snapon.com/catalog/item.asp?store=snapon-store&item_ID=68182&group_ID=3201
With that being said, even with decades of improvements - it's still a tedious task that can be time consuming and prone to false positives. This new implementation with multiple sensors will give the system a much higher success rate in less time - and when you're in an aluminum can a few hundred miles from the nearest breath of air, you want to find the source of your air leak as fast as possible.
uh, what do you think is LEAKING? (hint: "AIR!")
I work for the Department of Redundancy Department.
"conduct" would be a more appropriate word here than "transmit". Transmit seems to imply something that can be detected from a distance. This is just bolting sensors to the hull like sticking your ear to a water pipe to tell if water's running.
I work for the Department of Redundancy Department.
if the effect was limited just to the hull i'd agree, except that there is obviously a supply of air inside the spacecraft. it could be detected from a distance... inside the craft. which in principle could also be used to detect leaks.
Sigs are too short to say anything truly profound so read the above post instead.
This has got to be some very sturdy equipment. Ever watched a cockpit video of liftoff? Those are some heavy and prolonged vibrations. Think the vibrational sensors will still work to detect such subtle vibrations later after that much shaking for such a long time?