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Levitating and Manipulating Objects With Sound 59

Nerval's Lobster writes "Researchers at the University of Tokyo have published a paper and video describing a technique that is explicitly not an anti-gravity system, and doesn't pretend to be, but looks very much like one. 'The essence of levitation is the countervailing of gravity,' according to the provocative opening of a paper published Dec. 14 on the Cornell University science-publishing site arXiv.org that describes a way to not only raise an object into the air, but maneuver it in three dimensions using only standing waves of ultrasound. Since the mid-1970s, researchers have been able to levitate small objects using focused beams of high-frequency sound that bounce off a flat surface and create a wave of pressure that pushes the object into the air. But they couldn't cause an object to float, and they couldn't move it around in any direction other than up or down. The University of Tokyo team led by Yoichi Ochiai built a system that could raise small particles, water droplets and even 'small creatures' off a flat surface and zoom them around within an open, cubical area about 21 inches on each side. The system uses four sets of phased arrays – speakers producing focused beams of sound at around 40kHz – to create waves of ultrasonic force on every side of the object rather than just one. The force produced by each of the four ultrasound sources can be changed – and the force on the object manipulated – using the same techniques utilized by older systems. Coordinating the frequencies and force of ultrasound arrays on four sides, however, creates a consistent focal point for the force from each. By keeping frequency changes in sync, the system creates a 'bubble' within which the force from all four sources is consistent no matter where within the target area the focus is directed."
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Levitating and Manipulating Objects With Sound

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  • inb4 badbios + Maximum Overdrive + skynet + our new overlords mashup.

  • Youtube link (Score:5, Informative)

    by tabooli ( 927310 ) on Friday January 03, 2014 @01:08PM (#45858579)
    A link to video of this: http://www.youtube.com/watch?v=odJxJRAxdFU [youtube.com]
  • Here comes the 'I told you so' from the 'Survivors of Atlantis used sound to build the pyramids' peanut gallery.

    You know, like that couple from 'An Idiot Abroad' Egypt episode.

  • by mbeckman ( 645148 ) on Friday January 03, 2014 @01:23PM (#45858733)
    "...describing a technique that is explicitly not an anti-gravity system, and doesn't pretend to be, but looks very much like one."

    Um, it's basic physics. An actual force is moving an actual object, completely in compliance with standard Newtonian law. It no more "looks like" an anti-gravity system than does the Bernoulli effect when an airplane flies. The researchers demonstrate a novel use of ultrasound, but no more novel than superconductivity in a ceramic creating a magnetic field that can make a magnet hover in space. Using force. Just like you do when you hold something in the air with your hand.

    F = MA. Nothing anti about it.
    • Pretty sure they were referring to the device/setup itself, not the effect.
      • But it's not an anti-gravity device, either. Anti-gravity means canceling, or protecting against the effect, of gravity, using some kind of shielding or field that acts outside the standard laws of force. http://en.wikipedia.org/wiki/Anti-gravity [wikipedia.org]

        It does not refer to counteracting the force of gravity with some other force, such as electromagnetism or aerodynamic lift.

        Anti-gravity is currently science fiction.
        • I could just as accurately say "...describing a technique that is explicitly not an witch's broom system, and doesn't pretend to be, but looks very much like one."
        • It does not refer to counteracting the force of gravity with some other force, such as electromagnetism or aerodynamic lift.

          Or a table.

    • by Anonymous Coward

      Imagine using laser beans instead of sound waves. You would be able to accelerate an objet to ultimate speeds. Space travels!

    • It no more "looks like" an anti-gravity system than does the Bernoulli effect when an airplane flies.

      I think the point is that the absence of any visible means of support, wings, rockets, big balloons full of gas, whacking great magnets or other contrivances popularly associated with making things hang in the air - along with the failure to look like a bird - might make some people think it was an anti-gravity device. I'm sure that the first people to see a an aeroplane fly would have shouted 'anti gravity!' if birds and balloons hadn't pre-dated H.G. Wells.

      Presumably, though, an actual anti-gravity sy

    • It no more "looks like" an anti-gravity system than does the Bernoulli effect when an airplane flies.

      I made my science teacher cry one day. She kept insisting that the Bernoulli effect instead of angle of attack was what made airplanes fly. So I cannibalized my HO scale train set, and replaced my model airplane wings with barn doors. Then I flew it around in the park making faces at her, and asking her if she ever actually tests the bullshit they tell her to teach before brain damaging us. I mean, Look at the flat ceiling fan blades. Bernoulli? Bernoulli? Bueller?

      • Well, yes and no. For most airplanes, it's a combination of the Bernoulli effect and the angle of attack. However, it is, as you demonstrated, perfectly possible to build a practical airplane that relies solely on the angle of attack--stunt planes commonly do this, having wings with symmetrical cross-sections, as they regularly fly upside-down.

    • If this "looks very much like an anti-gravity system", then so does a hovercraft.

  • For the top of the learning curve, see the Coral Castle [rense.com].
  • by Anonymous Coward

    The same technology is already used by jet fighters to keep their windscreens clear. Audi is looking to bring this technology to their automobiles.

  • This is old news. (Score:1, Informative)

    by Anonymous Coward

    McLaren uses this technology on their latest road car. http://www.gizmag.com/mclaren-ultrasonic-windshield-wiper-washer/30205/

    • The ultra sonic windshield on military aircraft predates the wiper, and the standing ultrasonic wave in one dimension and two dimensional movement is old news -- Previous devices worked by bouncing a ultra sonic wave off a plate. This device has four emitters and can manipulate an object in three dimensions. The windshield doesn't do that. Ultrasonic welding doesn't do that either. Neither do the 2D ultra sonic suspensions. If the wiper-less windshield is your standard then you should cite your own voi

  • What is the point of this? I'm not trying to be sarcastic, but the article gives no hints about what this might be used for. I'd like to know.

    We all know what magnetic levitation is good for, but using loudspeakers to float a tiny object in a small box?

  • Sounds like an older sister at work.
  • We "countervail" the effect of gravity whenever we lift something. It might be said that we "countervail" the effect of gravity whenever we are not falling.

    Words DO have meanings, and according to the American Heritage Dictionary, antigravity means "The hypothetical effect of reducing or canceling a gravitational field." H. G. Well's fictional "Cavorite" in "The First Men in the Moon" meets that definition precisely.

    Ways of lifting and pushing things around without anything solid touching them are cool, esp

    • I support anti-gravity as a matter of principal. Why should the social construct of space-time curvature be considered so damn attractive? Just because a space isn't born curvaceous doesn't mean it shouldn't be considered equally attractive if it wants to be. If you actually cared to take a Shaman's Studies course you'd see that Gravitational bodies are blind to their science-rendered privilege.

  • Sonic screwdrivers! :D
  • So... ultrasonic 3D displays soon?
  • Sounds like this could work..just place the phased arrays on the bottom of the board, and let them push against the ground :)

  • This could be REALLY useful for assembling small, delicate systems in coordination with, say, 3D printing.

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