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Acoustic Levitation Works On Small Animals

Posted by ryuzaki0 on from the sounds-like-fun dept.

anthemaniac writes "Researchers for at least two decades have used acoustic levitation to suspend light materials without a container. Wenjun Xie, a materials physicist at Northwestern Polytechnical University in China, has previously used ultrasound fields to levitate globs of iridium and mercury, very heavy materials. Now the scientist has performed the feat with live animals. From the story: 'Xie and his colleagues employed an ultrasound emitter and reflector that generated a sound pressure field between them. The emitter produced roughly 20-millimeter-wavelength sounds, meaning it could in theory levitate objects half that wavelength or less.' Apparently the ants, spiders and ladybugs endured the trick just fine, but the fish didn't do so well due to lack of water."

8 of 182 comments (clear)

  1. Re:Biological heating effects? by Red+Flayer · · Score: 5, Informative

    Well, ultrasound is used to create the field... but the emitter that produces the waves for levitation has waves of much, much longer wavelength (and therefore much lower frequency). I think instead of at the molecular level, the concern would be at the macro level... that is, can animal tissue deal with rapid mechanical manipulation from the soundwaves?

    And is it possible for animals to have cavities or structures with a resonant frequency equal to that of the emitted waves? That's where the real danger lies, I think.

    --
    "Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
  2. Re:50 Hz? by cnettel · · Score: 5, Informative

    Ehum, only if sound travelled 1 meter per second in air. Hint: it doesn't. It's more like 340, hence the frequency is 50 * 340 = 17,000 Hz.

  3. Don't worry by PIPBoy3000 · · Score: 4, Informative

    They have magnetic levitation for fish and frogs.

  4. Re:Small Aminals? by Ungrounded+Lightning · · Score: 3, Informative

    A spider is an insect, not a aminal.

    Actually it's an arachnid, not an insect.

    (But I'd really like to know what an aminal is.)

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  5. Re:50 Hz? by jimstapleton · · Score: 3, Informative

    it'd have to be lower... it said "half the wavelength", in TFA, assuming 2 meters for a person (thats a bit over), This site (http://www.sengpielaudio.com/calculator-wavelengt h.htm) suggests that 85.75hz is what is needed. Using 6 feet people (12 foot wavelengths), we get 93.8hz

    --
    34486853790
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  6. Re:Small Aminals? by ookabooka · · Score: 3, Informative
    Wikipedia says that there are a bunch of different classification schemes, but even using the 6-kingdom model, you have Eubacteria, Archaebacteria, Protista, Fungi, Plantae, and Animalia. Of which a spider would fall into the catagory as an animal. If you look at the pylums (the next sub-catagory) a spider would be under Anthropoda which apparently stands for jointed feet.

    The success of arthropods is related to their hard exoskeleton, segmentation, and jointed appendages. The appendages are used for feeding, sensory reception, defence, and locomotion. The muscle system is more or less assisted by hydraulics originated from the blood pressure created by the heart [2]. The hydraulic system in spiders is especially well developed.


    So technically it IS an animal, and is closely related to crabs. . .*shrug* IMHO it is arguable since we humans always try to classify things into distinct catagories even though there are always exceptions, I'm sure someone will disagree w/ me.
    --
    If you are about to mod me down, keep in mind that this post was most likely sarcastic.
  7. Re:Biological heating effects? by theredmenace · · Score: 3, Informative

    You're concerned about organisms that contain MORE water? The specific heat capacity of water is greater than that of most materials, seems to me that more water would be a good thing.

  8. Seems like derivation from Bernoulli effect by tuomas_kaikkonen · · Score: 3, Informative

    To me the video seemed like two tubes that generated a derivation from Bernoulli effect.

    Some readers seem to mix up infra and ultra. Ultrasound is high frequency sounds.

    References:
    http://en.wikipedia.org/wiki/Bernoulli_Effect
    http://en.wikipedia.org/wiki/Ultrasound