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Boat Moves Without an Engine Or Sails

coondoggie writes "Researchers say technology they have developed would let boats or small aquatic robots glide through the water without the need for an engine, sails or paddles. A University of Pittsburgh research team has designed a propulsion system that uses the natural surface tension that is present on the water's surface and an electric pulse to move the boat or robot, researchers said. The Pitt system has no moving parts and the low-energy electrode that emits the pulse could be powered by batteries, radio waves, or solar power, researchers said in a statement."

37 of 234 comments (clear)

  1. Is it the Red October? by east+coast · · Score: 4, Funny

    *eom*

    --
    Dedicated Cthulhu Cultist since 4523 BC.
    1. Re:Is it the Red October? by Arker · · Score: 4, Interesting

      Err scratch that. Teach me to post in this heat.

      Apparently it relies on surface tension and would not, therefore, be very useful on a submersible vehicle. :((

      Might be nice for whale-watching and the like, at least. Engine noise scares off a lot of creatures that would otherwise be observable. But sailing ships are already quiet enough for that, so I'm not sure I see a real viable purpose for it at the moment.

      Still, just as pure research, it's pretty cool.

      --
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    2. Re:Is it the Red October? by MooUK · · Score: 5, Funny

      It's even lower energy!

    3. Re:Is it the Red October? by pato101 · · Score: 4, Insightful

      If I recall correctly, surface tension forces only count to steady state (low velocity motions). Thus, this thing (the story one) only will work at moderate speeds (look at the video: there are no waves in the surface because of the low velocity motion, also means high efficiency). What you propose would generate strong motions, which would kill the tension surface forces.

    4. Re:Is it the Red October? by psnyder · · Score: 3, Informative

      Might be nice for whale-watching and the like

      It would also be nice for whale communication, seeing as their ability to communicate over vast distances of ocean is significantly reduced by the background noise coming from mechanical engines in the water.

    5. Re:Is it the Red October? by Hognoxious · · Score: 3, Funny

      Or even rowers' energy?

      --
      Confucius say, "Find worm in apple - bad. Find half a worm - worse."
    6. Re:Is it the Red October? by afabbro · · Score: 3, Informative

      The Red October relied on complicated and only partially effective baffling to minimise cavitation IIRC.

      IIRC, the Red October ran primarily on fiction.

      --
      Advice: on VPS providers
  2. Watch the video by Ethanol-fueled · · Score: 3, Funny

    If they ever make that feasible for passenger boats then the passsengers better bring the Dramamine.

  3. Can't MHD already do this? by bistromath007 · · Score: 4, Interesting

    Sure, MHD drives that I know of are slow and run on superconductors, but that was back in the early 90's, they should be able to gin up something better by now.

    1. Re:Can't MHD already do this? by Anonymous Coward · · Score: 5, Informative

      MHD: Magnetohydrodynamics, for those that don't remember obscure acronyms.

  4. Calm water by Joebert · · Score: 3, Interesting

    Can this really work outside of a lab, where the water surface isn't like glass ?

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    1. Re:Calm water by Whiney+Mac+Fanboy · · Score: 4, Informative

      Can this really work outside of a lab, where the water surface isn't like glass ?

      It sure can work outside the lab. Check out the pics (search for figure 2 / figure 3) to see photos!

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    2. Re:Calm water by TapeCutter · · Score: 3, Insightful

      Good question. Many moons ago I worked the fishing boats in Bass Straight. Can it drive a semi-submerged fishing trawler 30 feet up at about a 15-20deg incline, or would gravity drag it backwards?

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    3. Re:Calm water by pato101 · · Score: 4, Interesting

      AFAIK, no: the tension surface forces are only strong when the surface is in almost steady state.
      I've forgotten most of these issues, but I recall solving tension surface problems, and there was a condition which meant almost steady state. The idea is that when the surface is in motion, convection and pressure terms become dominant over surface tension (the pressure gradients generated by convection are much larger than the pressure gradient due to surface tension).

    4. Re:Calm water by WindBourne · · Score: 3, Interesting

      I grew up on a lake as a kid. I used to watches similar bugs (and others). The answer is that they CAN go on waves as long as they are not breaking up. Once turbulent (white caps), then I never saw them. Though to be honest, it is possible that the wind simple blew them into shore and I did not notice. Typically, at high winds, I was more interested in sailing rather than swimming or water skiing.

      --
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    5. Re:Calm water by MightyYar · · Score: 4, Insightful

      No, no, feed them. It's fun to watch the racists all going ape-shit right now.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
  5. There is however one down side. by Anonymous Coward · · Score: 3, Funny

    The low-energy electrode that emits the pulse could be powered by batteries, radio waves, or solar power, researchers said in a statement."

    Caveat: said boat must be 8 inches long or less.

  6. Better Article by Selanit · · Score: 5, Informative

    The New Scientist article on this topic is more informative. Among other things, it's got a video of the test mini-robot boat in action.

    The water in the testing tank is very still -- there are few or no ripples. I wonder if the approach will actually work on, say, the ocean? If your propulsion system depends on steady contact with the water surface, waves are going to be a problem.

    1. Re:Better Article by arth1 · · Score: 3, Informative

      The New Scientist article on this topic is more informative. Among other things, it's got a video of the test mini-robot boat in action.

      The keyword here being "mini".

      When you weaken the surface tension, the surface raises a minute amount, which causes the vessel to slide off towards lower areas where the surface tension is intact. Raising the rear end of a RORO ship or passenger cruiser a millimetre or two isn't going to have much of an effect, methinks.

    2. Re:Better Article by YourExperiment · · Score: 5, Funny

      Raising the rear end of a RORO ship or passenger cruiser a millimetre or two isn't going to have much of an effect, methinks.

      RORORO your ship,
      Gently down a slope,
      Surface tension's far too weak,
      The whole idea is broke.

  7. Glittering diamond of hope *cough cough* by Oricalchos · · Score: 4, Funny

    Mother Nature called, she wants her gliding through the water patent back. Otherwise, it's neat. Innovation, even if it's copied from the nature, is welcome, especially in the years we have ahead of us. Just don't let it be another hoax.

  8. primary school chemistry, anyone? by arth1 · · Score: 5, Insightful

    We made boats that moved by weakening the surface tension back in primary school.
    Stick a piece of soap on the stern of a paper "boat", and it is propelled forward.

    However, I can't see how the surface tension would be strong enough to drive a full sized boat at any speed. At best you're talking about a few millimetres elevation difference between the bow and stern, if the water is very salty and there's absolutely no wind or currents causing waves.

  9. Never very practical by Anonymous Coward · · Score: 3, Interesting

    I few years back a Japanese boat was tested using a magnetic drive. It used the fact water moves in one direction in a magnetic field, air does the same thing and you can even make a fan with no moving parts that way. The problem was it only was able to hit a couple of miles an hours inspite of the massive magnetic field. There was even talk before that of high speed boats using the technique. It's more of a science curiosity than a practical means of propulsion.

  10. RTFA by Anonymous Coward · · Score: 3, Informative

    For all you harsh nay-sayers, the article is pretty clear that the tech's not for boats, but for small drones, robots and other things where fuel payload and moving parts are drawbacks.

  11. Re:Problems with their explanation by Anonymous Coward · · Score: 3, Funny

    This is the worst poem I've ever read.

  12. Boat moves without engine, paddles or sails by MichaelTheDrummer · · Score: 5, Funny

    commonly known as 'drifting'

  13. Re:for real by Anonymous Coward · · Score: 3, Funny

    Just break everything to 2cm pieces and send millions of boats.

  14. Yes but.. by Reed+Solomon · · Score: 5, Funny

    How effective is it at killing Manatees, hobo's of the sea?

    I refuse to use any sort of boat that doesn't maim or injure an endangered species. That's just the kind of forward thinking person I am.

  15. little slow? by Tree131 · · Score: 3, Insightful

    So, at 14.4 meters/h, this is only useful for bodies of still water.
    Looking forward to improvements in speed, 'cause I think ocean currents move faster than that.

    1. Re:little slow? by eggnoglatte · · Score: 3, Insightful

      Right. And speeding up horse carriages is just a matter of how many horses you use. Not.

      The fundamental power source here is gravity, by using the difference in elevation of the water surface with low surface tension at the back of the boat and normal surface tension in front. That elevation difference is tiny, and the power it can provide is therefore fundamentally limited.

  16. Re:Oblig by jd · · Score: 5, Funny

    In this case, it should be "does it run in Linux". (The answer is no. The surface tension is too low. The kernel mailing list tension, on the other hand, would be perfect.)

    --
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  17. "Boat Moves Without an Engine Or Sails" by overcaffein8d · · Score: 5, Funny

    Boat Moves Without an Engine Or Sails

    the vikings fixed this problem long ago.

    --
    Those of us who think they know everything annoy those of us who do.
    1. Re:"Boat Moves Without an Engine Or Sails" by Sibko · · Score: 3, Funny

      Boat Moves Without an Engine Or Sails

      the vikings fixed this problem long ago.

      They sure did.

  18. Re:Practical use? by plasmacutter · · Score: 4, Funny

    What are the advantages of this over using an engine or sail? Would it be friendlier to the environment, faster, or efficient?

    Whatever the practical application, this is cool!

    It's a brilliant way to ship your toothpicks overseas one at a time.

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  19. No, it is not even remotely similar. by Jane+Q.+Public · · Score: 4, Informative

    MHD consisted of the manipulation of a magnetic slurry inside a flexible structure (usually a tube), which in turn mechanically pushed water to the rear, thus achieving thrust.

    Picture a large, straight colon, shoving diarrhea rearward via peristalsis: this was the basis of the MHD drive. It had nothing to do with surface tension, nor did it manipulate water directly via magnets or any other means.

  20. Re:for real by sapphire+wyvern · · Score: 4, Funny

    I think that's called the BoatTorrent protocol.

  21. The rime of the ancient mariner (Iron Maiden) by nomorecwrd · · Score: 5, Informative

    There, calls the Mariner,
    there comes a ship over the line
    But how can she sail with no wind
    in her sails and no tide.

    (Based on "The rime of the ancient mariner" [1797 - 1798] by Samuel Taylor Coleridge )

    Any other Iron Maiden fans out there in ./?
    ...
    hello?