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Robots That Bounce on Water

Posted by CmdrTaco on from the something-about-tigger-goes-here dept.

inghamb87 writes "The way water striders walk on water was discovered years ago. The insect uses its long legs to help evenly distribute its tiny body weight. The weight is distributed over a large area so that the fragile skin formed by surface tension supports the bug on the water. However, the ability of water striders to jump onto water without sinking has baffled scientists, until now." If nothing less, you need to see the picture: it's awesome.

17 of 137 comments (clear)

  1. Jesus by hernyo · · Score: 5, Funny

    Did Jesus use the same technology?

    1. Re:Jesus by pushing-robot · · Score: 5, Funny

      No, that was Mecha-Jesus.

      --
      How can I believe you when you tell me what I don't want to hear?
    2. Re:Jesus by Kranfer · · Score: 4, Funny

      As a jew, I am forced to say yes... along with his Jedi powers of turning water into wine and healing as well. ::smirks::

      --
      -- Josh
      "Whoopie! Man, that may have been a small one for Neil, but that's a long one for me!" - Pete Conrad
  2. Grammar!!! by dsginter · · Score: 4, Funny

    If nothing less, you need to see the picture: it was awesome.

    There. Fixed that for you.

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    More
    1. Re:Grammar!!! by PlatyPaul · · Score: 5, Informative

      Well, if you don't mind the sources, check out this alternate coverage (with pictures):

      Telegraph.co.uk article
      ENN article

      --
      Misery loves company. Online misery loves unsuspecting random strangers.
  3. I for one... by Bazman · · Score: 4, Funny

    welcome our new water-walking robotic overlords... with some surface-tension reducing soap :) Muahahahahahah!

    1. Re:I for one... by dsginter · · Score: 4, Informative

      with some surface-tension reducing soap

      I'm gonna take a guess to say that you learned this from Mr. Wizard?

      I remember this episode well - it is a simple but very awe-inspiring (at least from a geek's perspective) experiment. It goes like this:

            1) Fill a cookie tray with water
            2) Pepper the top of the water in order to *see* the movements of the surface tension
            3) Carefully place a small amount of soap in the center of the tray
            4) Watch the pepper scatter to the edges of the pan as the tension breaks

      If you have a kid, then you need to go do this experiment with them NOW!

      RIP Don Herbert - you are one of the main reasons that I am a geek today.

      --
      More
    2. Re:I for one... by SQLGuru · · Score: 4, Funny

      I'm sorry....all of my foil is being used to make hats.

  4. My Life IS RUINED! by explosivejared · · Score: 3, Funny

    All my life I've been waiting to see an awesome picture about FRIKKIN ROBOTS THAT BOUNCE on water, and now it's apparently slashdotted! I'm gonna cry now.

    P.S. Hey taco if this is just some sick joke, and you gave a busted url, I'll kill you! Robots on water... you don't play around with that!

    --
    I got a catholic block.
    1. Re:My Life IS RUINED! by ookabooka · · Score: 5, Informative

      See, my life just got better because I have a great excuse to karma whore. Yay nyud mirror

      --
      If you are about to mod me down, keep in mind that this post was most likely sarcastic.
  5. The Picture Might Be Worth It... by __aagmrb7289 · · Score: 3, Interesting

    But I believe we've had a theory for this for awhile now. In August of 2003, MIT published some information on the subject. Here's a link:

    http://web.mit.edu/newsoffice/2003/robostrider.html

    Here's some relevant content from that link:

    MIT researchers report in the Aug. 7 issue of Nature that they now understand how the insects known as water striders skim effortlessly across the surface of ponds and oceans.

    And:

    Using mathematics, high-speed photography and a variety of flow visualization techniques, Bush, mathematics graduate student David L. Hu and mechanical engineering graduate student Brian Chan uncovered the true way in which water striders walk on water.

    As the insect rests on the surface, the tips of its thin legs create miniscule valleys. It sculls the middle set of its three pairs of legs like oars, causing the water behind those legs to propel it forward as the surface of the valley rebounds like a trampoline. Although the rowing motion does create tiny waves, "the waves do not play a significant role in the momentum transfer necessary for propulsion," the researchers wrote. "The momentum transfer is primarily in the form of subsurface vortices."

  6. Rather short on information... by damn_registrars · · Score: 4, Interesting

    I managed to view the site before it went down in flames under the slashdot effect. The picture was cool, but the article left much to be desired:

    How big is the robot?
    How much does it weigh?
    How fast can it move?
    How is it controlled?
    What is the range of speeds for this that was mentioned in the article?
    They mentioned applying it to sampling water quality, but wouldn't that disrupt the surface tension to sample the water right under the robot?

    --
    Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
  7. Baffles science? by EmbeddedJanitor · · Score: 4, Informative
    Here's a related link: http://www.livescience.com/animals/041103_water_strider.html

    This one is erroneous in at least one way. It suggests that tiny bubbles trapped in hairs on the bug's legs make it float. Tosh! The bubbles are too small to make it boyant. What the bubbles do is increase the surface area which, in turn, increases the amount of surface tension "skin" that the bug walks on and therefore the carrying capacity.

    As most fly fishermen would tell you, surface tension is far stronger than you'd think. Hatching bugs struggle to get through the surface tension which keeps them under the surface. Once they break through they are able to sit and walk quite easily.

    --
    Engineering is the art of compromise.
  8. Never, ever, EVER do that! by Un+pobre+guey · · Score: 5, Funny
    If nothing less, you need to see the picture: it's awesome.

    Never put a line like this in a /. summary. Do you want Congress to pass a law classifying /. as some kind of cyber-terror weapon? You can almost see smoke coming out of the ground around these poor bastards' data center.

  9. This is a crock of shit by EmbeddedJanitor · · Score: 4, Informative
    This is not science. This is bullshit.

    The "robot" spreads its weight out using the whole length of its legs in contact with the water. That is nothing like a water strider.

    A water strider walks on the **ends** of its legs (feet, if you will). For a far better description see http://www.livescience.com/animals/041103_water_strider.html.

    The only similarity is that they both use surface tension.

    --
    Engineering is the art of compromise.
    1. Re:This is a crock of shit by Chris+Burke · · Score: 3, Insightful

      This is not science. This is bullshit.

      Of course it's fucking science, even if it isn't exactly what you hoped it would be. What makes this "not science"?!

      The "robot" spreads its weight out using the whole length of its legs in contact with the water. That is nothing like a water strider.

      So? So our robots aren't nearly as light as a water strider (I guarantee you the robot pictured weights a lot more than 15x a water strider), and require much greater surface area to stay afloat. Also we can't create legs with the tiny micro-hairs that allow the strider to stay afloat and jump on water so easily. What do you know, nature still wins, and we still have a lot of work to do to duplicate it.

      If that's the standard, pretty much all science is bullshit.

      The only similarity is that they both use surface tension.

      Well according to your link water striders don't even rely on surface tension.

      Nevertheless: Water-walking robot. Some people would think that's cool. But that would be those of us who appreciate advancements in the state of the art, not those who think anything less than the end goal is a 'crock of shit'.

      --

      The enemies of Democracy are
  10. Bigger version of the "awesome" picture by SiliconEntity · · Score: 3, Informative

    That picture is not actually from the new research, it is from old work at Carnegie-Mellon. Here is a bigger version:

    http://nanolab.me.cmu.edu/projects/waterstrider/STRIDE_water_strider_big.jpg

    It is part of the work of the NanoRobotics Labaratory at CMU.