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Robotics Science

Robots That Bounce on Water 137

Posted by CmdrTaco 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.
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Robots That Bounce on Water More

Robots That Bounce on Water

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  • Jesus (Score:5, Funny)

    by hernyo ( 770695 ) <laszlo.hermann@gmail.com> on Monday December 10, 2007 @12:28PM (#21644201)
    Did Jesus use the same technology?

    • Re:Jesus (Score:5, Funny)

      by pushing-robot ( 1037830 ) on Monday December 10, 2007 @12:30PM (#21644243)
      No, that was Mecha-Jesus.

    • Re:Jesus (Score:5, Funny)

      by Kranfer ( 620510 ) on Monday December 10, 2007 @12:30PM (#21644245) Homepage Journal
      As a jew, I am forced to say yes... along with his Jedi powers of turning water into wine and healing as well. ::smirks::
      • Are you saying that these are talents jews have, including yourself and Jesus? Cool! By converting to judaism, can others get these talents, or does it only pass from the mother? Right now all I can do is turn wine into water. That's what I love about diversity: you get to learn all sorts of interesting things about other cultures and races. I wonder what other powers people are keeping secret...
        • Actually, we can't do any of that. The only super-power Jews possess is that of irrational self-criticism.

          • Re: (Score:2)

            by Gilmoure ( 18428 )
            But, but, Mel Brooks said that one in ten Jews is really funny.

            (love the GOV coat)
            • One in ten isn't really much of a people-wide ability (though it is true, and some families have more Funny Jews than others).

              BTW, what's a GOV coat?

              • Re: (Score:3, Insightful)

                by Gilmoure ( 18428 )
                In Blazing Saddles, Mel Brooks (playing the governor) wears a coat with GOV on the back. In Hebrew, Gov mean back. Funniest thing I've ever seen.

        • Re: (Score:2)

          by Abreu ( 173023 )

          By converting to judaism, can others get these talents, or does it only pass from the mother?
          I think the prerequisites for that prestige class are a lot more strict... Besides the (racial?) requirements, you probably need some divine feats... not to mention the strict alignment restrictions...

          All in all, you are better off taking a few levels of sorcerer...

        • Re: (Score:2)

          by arivanov ( 12034 )
          Slashdot needs a "+1 Troll" besides the "-1 Troll" mod. For posts like yours. Applause.

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

        Last I checked, Jesus was Jewish...

        • Re: (Score:3, Funny)

          by Dr Caleb ( 121505 )
          "Last I checked, Jesus was Jewish..."

          What? You actually walked up to him asked him to 'whip it out' and verified his circumcision?

          • What? You actually walked up to him asked him to 'whip it out' and verified his circumcision?

            Naw - my time machine is out for repair. I just read the bible instead.

      • Re: (Score:2)

        by eonlabs ( 921625 )
        Hate to break it to you, but Jesus was a level 4 druid: http://www.dandwiki.com/wiki/SRD:Druid_Spell_List [dandwiki.com]
    • No, but politicians often use this technology to avoid submersion in their own bullshit.

    • Re: (Score:2)

      by 7Prime ( 871679 )
      Lol, that reminded me of a George Carlin sketch, in which, while narrating Jesus, he describes one of his diciples who got jealous and tried to invent some water walking shoes, with hillarious results.

  • Grammar!!! (Score:5, Funny)

    by dsginter ( 104154 ) on Monday December 10, 2007 @12:29PM (#21644213)
    If nothing less, you need to see the picture: it was awesome.

    There. Fixed that for you.

  • I for one... (Score:5, Funny)

    by Bazman ( 4849 ) on Monday December 10, 2007 @12:29PM (#21644225) Journal
    welcome our new water-walking robotic overlords... with some surface-tension reducing soap :) Muahahahahahah!

    • Re:I for one... (Score:5, Informative)

      by dsginter ( 104154 ) on Monday December 10, 2007 @12:46PM (#21644513)
      with some surface-tension reducing soap

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

      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 [npr.org] - you are one of the main reasons that I am a geek today.
      • IIRC, he used lycopodium powder on the surface. Not quite sure why that stuck in my brain for the last 20 years.

        And yes, I think a lot of us owe our geekness to Mr Wizard. Off the top of my head, I remember the water displacement in the blue barrel with the kid who was freezing, the snow melting in the microwave, the telescope, the papercutting and jumping through it, the illusion of fading into a skeleton, and one of those shorts in it where they heated the pebbles to provide better traction on ice.

        • Re: (Score:2)

          by ahsile ( 187881 )
          The one that always stuck with me was the water pressure/pump experiment. Trying to pull water up as many stories as you could with a giant straw!

        • Re: (Score:2)

          by HTH NE1 ( 675604 )

          IIRC, he used lycopodium powder on the surface. Not quite sure why that stuck in my brain for the last 20 years.

          I know why it is stuck in mine: he used it in several experiments, both with water and also to simulate a grain mill explosion. And I'd watched the same episodes repeat countless times on Nickelodeon back when it didn't have commercials other than for shows on the network (listing air times in four timezones).

          I don't recall him ever using the word "hydrophobic", but I think he did say "meniscus" once.

      • Alternate experiment:

        Create a "boat" out of aluminum foil. Shape it like a square with a triangle appended to one edge, and fold slightly. Cut a small slit on the back of it (opposite the point), and place carefully on the surface of the pan filled with water. Carefully place a small drop of dish soap onto the slit, and watch the surface tension propel your boat forward!

      • Re: (Score:2)

        by ceoyoyo ( 59147 )
        Whew. I thought you were going to say that you put a water strider on a pan of water and then sank it. I was all ready to call PETA, make popcorn and watch the fun.
      • I learned this one in high school.
        Take a small pitri dish or something similar and fill with milk.
        Place drops of several colors of food coloring in different areas.
        Place a drop or 2 of dishsoap in the middle.
        Watch the colors swirl all around as the soap reduces the surface tension.

      • Re: (Score:2, Funny)

        by dstiggy ( 1145347 )

        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
        5)???
        6)Profit!!!

        fixed that for you

      • Re: (Score:2)

        by raddan ( 519638 )
        I personally learned this one from my photo tech class in high school (do they still have that class anymore?). There was a chemical that we dipped our developed and fixed film in to prevent water spots from forming on them as they dried. Water just ran right off onto the floor. My teacher casually brought up soap when explaining how this works. Ah, soap! I knew it had a use ;^)

    • Re: (Score:2)

      by 7Prime ( 871679 )
      I see a sudden spike in the sales of PhotoFlow(tm) in the near future. Especially among paranoid organized crime syndicates who happen to be next to lakes.

  • My Life IS RUINED! (Score:4, Funny)

    by explosivejared ( 1186049 ) <hagan.jaredNO@SPAMgmail.com> on Monday December 10, 2007 @12:30PM (#21644239)
    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!
  • Site is being destroyed by /. - give us a mirror!

  • The Picture Might Be Worth It... (Score:4, Interesting)

    by __aagmrb7289 ( 652113 ) on Monday December 10, 2007 @12:35PM (#21644317) Journal
    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 [mit.edu]

    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."

    • Re: (Score:2, Informative)

      by Anonymous Coward
      That's how they walk on water. This is how they jump.
      • Oh! Gotcha. Unfortunately, I'm still trying to get the article to load, and I must have misread the summary.

        Thanks.

        • Re: (Score:3, Interesting)

          by __aagmrb7289 ( 652113 )
          Article Content (even Google cache is REALLY slow):

          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.

          A team of researchers at Seoul National University, led by Ho-Young Kim and Duck-Gyu L

          • A team of researchers at Seoul National University, led by Ho-Young Kim and Duck-Gyu Lee, has finally answered that question. By using a highly water-repellent sphere, which mimicked the actions of the water strider's highly water-repellent legs, they were able to determine a small range of speeds at which the sphere or insect could hit the water and not sink.

            This does remind me of the cutting-edge technology developed in Britain say, oh, 65 years ago? http://en.wikipedia.org/wiki/Bouncing_bomb [wikipedia.org]
            Good to kn

    • Re: (Score:2)

      by bkr1_2k ( 237627 )
      Yes, as the summary stated, how they walk on water was discovered a while ago. How they get onto the water from land without breaking the surface tension was what this new research was about.
      • Yes, this was pointed out a few hours ago, and I responded. Feel free to check the thread. You know, RTFT? ;)

  • Rather short on information... (Score:5, Interesting)

    by damn_registrars ( 1103043 ) <damn.registrars@gmail.com> on Monday December 10, 2007 @12:35PM (#21644321) Homepage Journal
    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?

    • Re: (Score:1, Funny)

      by Anonymous Coward
      You left out the most important question of all:

      Does it give you 30 seconds to comply?
    • Comment removed based on user account deletion

  • Great (Score:2, Funny)

    by gowakuwa ( 1199733 )
    So Jesus was an insectoid alien or an intergalactic robot? Either way it had to be hard to intelligently design him, or her.

  • Baffles science? (Score:5, Informative)

    by EmbeddedJanitor ( 597831 ) on Monday December 10, 2007 @12:38PM (#21644389)
    Here's a related link: http://www.livescience.com/animals/041103_water_strider.html [livescience.com]

    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.

    • According to the article it is the "jumping onto water without sinking" which was baffling, not the walking part, which, as you pointed out, has been understood for some time.
  • If nothing less, you need to see the picture: it's awesome.

    If you're one of the four people who got to see the picture before it became Slashdotted....
  • The original article link is down, so can't tell if its old news, but I remember reading a similar article on slashdot earlier about the 'baffling' mystery of water striders being solved?

    MIT Robot Walks On Water
    http://science.slashdot.org/article.pl?sid=03/08/26/0141229/ [slashdot.org]
  • Here is the cached image [blogspot.com].
  • Here's the Telegraph story linked in the blog entry we just hosed:

    http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/12/07/sciwater107.xml [telegraph.co.uk]

    Yes, it's dated July 12, 2007. Yes, you must be new here.

  • Never, ever, EVER do that! (Score:5, Funny)

    by Un pobre guey ( 593801 ) on Monday December 10, 2007 @12:47PM (#21644525) Homepage
    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.

    • The traffic isn't that bad. We just had to talk to them a bit about caches and linking directly to dynamic pages. We also temporarily raised the caps on their virtual server and adjusted the Apache configuration for this type of traffic.

      -Sitelutions Team
  • (*) It will be fought by entrenched fishing interests

  • Mirror / Additional Content (Score:2, Informative)

    by Anonymous Coward
    Coral Cache seems to have a mirror of the image.
    http://aycu05.webshots.com.nyud.net:8090/image/34684/2000802596361707173_rs.jpg [nyud.net]

    The article also links to this one, which has a different water walking robot overlord picture.
    http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/12/07/sciwater107.xml [telegraph.co.uk]

  • Water Striders... (Score:2, Interesting)

    by homgran ( 766092 )
    I remember going to a conference presentation by John Bush [mit.edu] back in 2005 which detailed the physics behind water striders. His presentation was very good, and the video footage he presented was absolutely fantastic (see here [mit.edu] and here [mit.edu]). I think the work referenced in the main article isn't quite as groundbreaking as they'd have you believe. There has been quite a lot of work in this area over the last five years.

  • hah (Score:1)

    by jovius ( 974690 )
    Oh, the laughter of the water striders... see you in a million years, suckers!
  • I got through, and uploaded it to imageshack in case it goes down again or I was just lucky in getting through.
    http://img155.imageshack.us/img155/6365/slashdottedqf9.jpg [imageshack.us]
  • well, bounce my shiny metal ass

  • Bigger version of the "awesome" picture (Score:4, Informative)

    by SiliconEntity ( 448450 ) on Monday December 10, 2007 @02:11PM (#21645779)
    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 [cmu.edu]

    It is part of the work of the NanoRobotics Labaratory [cmu.edu] at CMU.
  • Wouldn't a little boat be just as efficient (if not more) without all of the robot research.
  • Now all we need is worm-like robots that burrow through the earth. And of course earwhig robots that burrow into your ear, and tick robots that attach to your skin and suck your blood. Cock roach robots won't need to do anything except run around and freak people out because they're so icky. Then, without a shot being fired, hasta la vista Sarah Conner.
  • ... can they carry lasers?
  • Come on! The first thing I thought of was 'cool! we can do Rover's on Europe or Titan where we have liquid gas!

    I see more use for this in space than here. A spy robot that walks on liquid? I'd love to see pictures from Titan where it walks out over the liquid air.

    And I'd have to say that such a robot would be a true all terrain robot...it could zip around the coast lines looking for life.
  • Wait 'til I get this out on the 'hooch!

    Hey y'all! Watch this!
  • Last week, Oak Ridge announced development of a material that is virtually unwettable [ornl.gov], a nanoetched powder that acts on surface tension and can be applied as a coating to almost any surface. A boat with a coated hull would become a water strider - one continuous stride. Much cooler news than this article.
  • Some how I think this robot will be marketed for evangelical [newgrounds.com] purposes. And for that reason IT MUST BE DESTROYED!

    *In the voice of that BS Billy Graham book advert*
    Have you ever wondered why God never allowed for you to have the rich fullfilling life you think deserve? Are you tired of waiting for the rapture for God to smite democrats, Catholics, Muslims, people who hate George Bush, teachers who teach Darwinism, the Internet, and everyone else except for you and all your elitist God-fearing friends?
    Intro

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