top | item 10463175

Sonic tractor beams that can lift and move objects using soundwaves

53 points| yitchelle | 10 years ago |theguardian.com | reply

18 comments

order
[+] Natanael_L|10 years ago|reply
Would be cool to see some ISS astronauts use something like an ultrasonic transducer array to demonstrate this in front of cameras in zero-gravity, pointing it against objects and making them spin and move forwards and backwards at will. (Yes it could be done in high-altitude planes moving in arcs too, but that's slightly less cool.)

Actually it could potentially even (if it doesn't use too much energy) be used as a transport method for objects inside ISS, by having stationary transducer arrays pushing objects to where they are needed. :)

[+] jychang|10 years ago|reply
Sorry for being a wet blanket... but for some reason I don't think the ISS will want high power vibration generators near all their sensitive experiments.
[+] amelius|10 years ago|reply
Actually, I think this is much cooler on Earth, where it can "defy" gravity :)
[+] JibberMeTimbers|10 years ago|reply
How would that work since there is no sound in space? As I understand, sound vibrates against molecules drifting around and since those molecules don't exist in space, it wouldn't work.
[+] craigjb|10 years ago|reply
It's too bad ultrasonic transducers this size (~16mm) are too large to make a linear phased array with high angle range and low grating lobes [1]. This means that a different object or particle might be manipulated simultaneously with the target object.

I've been looking into using a genetic search or just brute force random search to create a randomized transducer pattern that minimizes grating lobes though. You can purchase these transducers in bulk for super low prices though! So anyway to build a capable phased array with them would be awesome.

[1] http://www.microwaves101.com/encyclopedias/grating-lobes

[+] anonymfus|10 years ago|reply
I don't understand how British newspaper can put Star Wars references in the article where Doctor Who is much more relevant.

http://www.youtube.com/watch?v=fvhbGGkhKe4

[+] parfe|10 years ago|reply
Probably because more people saw the last star wars film opening weekend than have watched doctor who in its entire history.
[+] hellbanner|10 years ago|reply
Can someone explain to me how sound waves can move something towards the source of the wave?
[+] mtreis86|10 years ago|reply
Not a physicist. I think, if you get a standing wave going, say on a drum surface, and slowly change the frequency slightly up or down, a piece of rice sitting on the drum can be moved around. The rice will tend to settle between nodes. If you have significant enough energy, the interference patterns can 'drive' an object. Apparently this can be done in midair, with enough energy to break gravity. And can be entirely controlled. Sweet.

Edit, spelling.

[+] Natanael_L|10 years ago|reply
Because you control the air pressure waves (sound) well enough that there's a pressure peak (slightly more dense air) right behind the object, with lower pressure in front of it (less dense air) on average.

That would force it to move towards you if you can overcome any friction and other counteracting forces.

[+] Practicality|10 years ago|reply
Too bad this wouldn't actually work between spacecraft since you need air molecules (or some other medium) for the sound waves to work with. Still a neat idea though.
[+] JoeAltmaier|10 years ago|reply
WOnder if it works better or worse under water...