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Hand-held "Sound Camera" Shows You the Source of Noises
Zothecula writes "If you work with machinery, engines or appliances of any type, then you've likely experienced the frustration of hearing a troublesome noise coming from somewhere, but not being able to pinpoint where. If only you could just grab a camera, and take a picture that showed you the noise's location. Well, soon you should be able to do so, as that's just what the SeeSV-S205 sound camera does."
Good device required here.... picture not required.
I sure could have use that a few years ago. I had a rattle in my car that sounded like it was coming from behind the dash, and it was driving me nuts. I freed the dash from its mount points and drove around the block with the dash hanging in the breeze. It definitely help identify the rattle. It was the visor!
Old but cool mechanic's trick: use a screwdriver. Place the metal against a running engine, put the ( plastic or wood ) handle against your ear. Hear amazing things inside of the running engine.
Religous speak to God. Insane are spoken to by God. When all shut up, one can finally hear Shostakovich in peace
Don't know about this particular project, but back when I did my PhD, I open-sourced my sound localization algorithm. Tracks up to ~4 moving sound sources in real-time using 8 microphones.
Opus: the Swiss army knife of audio codec
That's got to be the most exciting tech toy I've heard of in a long time. Kudos to those bringing this to life.
Don't trust anything that bleeds for a week and lives.
So if you're looking for that you can skip reading the article.
How long before we can extend this Aliens-wise and get a working motion tracker?
Because that's really the only time when it's impossible to know where the hell the sound is coming from in my experience.
for finding mice. (Yeah, I realize a cat works, but then you have to take care of the cat).
Finally! One step closer to finding all those cursed Annoy-a-Trons!
Knowing where the sound comes from is quite handy, but often that's only half the battle - knowing what kind of sound it is is equally important.
A 'ping' coming from your engine block has an entirely different mechanical connotation than a knock or whine from the same region.
Still cool, can't wait to see what lies ahead.
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Dude, I don't care how you call the planet, but it already has Earth Day!
Today is Mother's Day!
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Just you.
And close your door when you do that, for crying out loud.
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Make it recognize those loud thumping cars with subwoofers and connect an automated laser to it.
The problem of antisocial jerks who like to annoy hundreds of people will be solved quite rapidly!
to find that damn cricket that woke you up at 3am
A ball inside a ball-bearing race typically fails by "spalling": a tiny flake breaks off of the surface of the ball.
As it rolls around the race, the ball makes a periodic "tick" sound whose frequency is related to its rotation.
So... if you record the sound coming from an engine, and you have an index mark input (when the flywheel reaches TDC, for instance) and you know the gearing ratios of all the shafts, the inner race and outer race diameter of the ball bearing races, and the number of balls &c you can relate the frequency to a particular bearing which is going bad before it fails.
You can do the same thing for the races: the inner and outer races rotate with a particular speed relative to the balls, so a crack or spall on a race will also make a sound at a particular frequency.
Essentially, look for energy in the particular frequency that a particular failure in a particular bearing would make based on the engine RPM, and repeat for all races. If you find enough energy (ie - audio volume), you know which bearing is going bad and the nature of the problem.
A bad gear typically starts with a broken tooth: a crack forms at the base of the tooth, resulting in a tooth which doesn't push as hard against the mating tooth in the next gear. This causes the driving shaft to speed up slightly as the cracked tooth mates, and slow down for the next tooth due to inertia.
If you continuously monitor an accelerometer attached to one of the engine shafts you can see this speedup/slowdown signature, and if you know the gearing ratio you can figure out which gear is going bad within the engine. The crack tends to mature over time, so an individual tooth will first become "wobbly" before complete failure.
A Journal Bearing typically wears when the "hole" becomes bigger than the shaft (the oil and mating shaft grind the hole bigger over time). When this happens, the mating shaft and attached mechanics will "wobble" within the hole, causing a noticeable shift in the mass of the engine.
If you continuously monitor an accelerometer attached to the engine block, you can index this wobble to the shaft speed based on the engine RPM and tell if any bearings are failing and how bad they are.
In all cases you can determine the nature and extent of the damage while it is relatively minor - before it damages other parts of the engine (scored shafts, pieces breaking off, catastrophic failure in flight, &c.)
At the time this was figured out the technology was expensive to implement, so it was only appropriate in select situations - aircraft maintenance, for instance.
Nowadays with the rise of high-power microprocessors and personal phone displays, perhaps some enterprising hobbyist will figure out a way to implement this for automobile maintenance.
Soon we will see this in CSI episodes.
But it will be even better, every single CCTV camera will be automatically updated to include this, and they will track sound reflecting off walls off walls of peoples ears off walls.
I can't wait for science!
I don't always avoid Women, but I do deny them my essence.
We were using a variant of this to help balance helicopter blades. Put accelerometers on the frame, [carefully] run up the engine while tethered, analyze the vibration, advise the tech how to adjust the blade weights, and repeat. Eventually you get well-balanced blades.
A similar system could diagnose wheel and tire issues. Mount an accelerometer and a microphone on the frame near each of the wheels and try to detect vibration and/or frequencies that correlate with wheel or shaft rotation, and frame vibration.
I'd love to have an onboard diagnostic that shows an X-ray diagram of the engine drive-train, with green/yellow/red circles around the various parts and listings detailing the type of part and level of health.
You could also implement active balance compensation.
You can never balance anything exactly perfect, but if you can measure and analyze the balance you can compensate for minor imperfections. An electromagnet mounted near a shaft can "pull" the shaft slightly at the right point in its rotation, compensating for a tiny amount of imbalance.
For small values of "compensate", you can tune your mechanical system to be much quieter and have much less wear. The same system can measure the amount of compensation needed, and alert the user when the engine exceeds the system's ability to compensate.
Lots of interesting possibilities here for active computer-control of mechanical systems.
Check these out for more info:
"Detection of rolling Element Bearing Damage by Statistical Analysis" by D. Dyer and R.M. Stewart (Journal of Mechanical Design)
"Envelope Analysis - the Key to rolling-element bearing diagnosis" by Joelle Courrech and Mark Gaudet" (Bruel & Kjaer Application Note)
Now we need one that shows the source of a smell (at least, my family certainly does).
The quietest time of the day-night. I dream of those 100-dollar bills flying away to plumberland.
Wouldn't it damage your hearing?
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If it needs a 100m runway isn't it really just an untra-light plane?
A Helicopter is much closer to a flying car than this thing...
I worked at a power station with steam-driven turbines where this sort of sound camera could be very useful. The discharge side of these turbines are kept in a vacuum state to pull steam through more efficiently. Unlike most leak where you see or feel what's coming out, vacuum leaks suck inward and sound is the best way to locate them. The ambient noise in a power station prevents use of ears until you're mere inches from the source and several people could spend days in that type of search. The only aid we had was a sound detector tuned to the frequencies normally produced by a vacuum leak. I never found a leak using one and think very few were ever found by other users. (We just slapped tape and other sealants on likely trouble spots and waited to see if relevant gauges changed.) This would also be a great place to look at bearings for a range of motors and pumps as well as motor and air-operated valves for signs of air leaks and failing parts. Great technology. Hope it pans out.
My first reaction was military application. The moment the sniper fires a shot this passive device would tell its (dehumanization) exact position.
'Once scientists, even the dim-witted social scientists, get muzzled, the Western Civilization is finished.' - oldhack
http://googlesystem.blogspot.ru/2013/02/chrome-shows-which-tab-is-making-noise.html
Obviously, this would work for propellers and tail rotors, too. Careful design should make it invisible, or reduced visibility to the pilot. If that were a bad thing. Time, hopefully, will tell.
Again, good luck!
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There's a ghost in my house that makes a lot of noise
And it moves around
Since it's "transparent" I can't "see" it
Now, with this gadget I got to "see" where it's making the noise that it's making
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It might be useful if you were infected by one of these.
A simple backpropagation neural network could correlate the learning pairs of sound (or sound,make,model,year,engine location) and problem.