Follow Slashdot stories on Twitter

 


Forgot your password?
Close
typodupeerror
×
Transportation Technology

Boat Moves Without an Engine Or Sails 234

Posted by samzenpus from the watching-too-much-seaquest dept.
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."
This discussion has been archived. No new comments can be posted.

Boat Moves Without an Engine Or Sails More

Boat Moves Without an Engine Or Sails

Comments Filter:

  • Is it the Red October? (Score:5, Funny)

    by east coast ( 590680 ) on Wednesday January 21, 2009 @11:40PM (#26556369)
    *eom*

    • Re: (Score:2, Funny)

      by Anonymous Coward

      Listen to it at 10 times speed.

    • Re: (Score:2)

      by Arker ( 91948 )

      If this works as advertised it could be very useful for submarine propulsion. The Red October relied on complicated and only partially effective baffling to minimise cavitation IIRC. This method would eliminate cavitation entirely.

      • Re:Is it the Red October? (Score:5, Interesting)

        by Arker ( 91948 ) on Thursday January 22, 2009 @01:12AM (#26556915) Homepage

        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.

      • Not baffles, 'hydro-magnetic drive' IIRC. Described in the book and film as 'like a jet engine for the water...very quiet'.

        So, no baffles, but lotsa bullshit!

      • Re:Is it the Red October? (Score:4, Informative)

        by afabbro ( 33948 ) on Thursday January 22, 2009 @11:32AM (#26561043) Homepage

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

        IIRC, the Red October ran primarily on fiction.

  • Watch the video (Score:4, Funny)

    by Ethanol-fueled ( 1125189 ) * on Wednesday January 21, 2009 @11:41PM (#26556373) Homepage Journal
    If they ever make that feasible for passenger boats then the passsengers better bring the Dramamine.

  • Can't MHD already do this? (Score:5, Interesting)

    by bistromath007 ( 1253428 ) on Wednesday January 21, 2009 @11:47PM (#26556411)
    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.

  • Calm water (Score:4, Interesting)

    by Joebert ( 946227 ) on Wednesday January 21, 2009 @11:51PM (#26556447) Homepage
    Can this really work outside of a lab, where the water surface isn't like glass ?

    • Re:Calm water (Score:5, Informative)

      by Whiney Mac Fanboy ( 963289 ) * <whineymacfanboy@gmail.com> on Thursday January 22, 2009 @01:21AM (#26556941) Homepage Journal

      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 [mit.edu] the pics (search for figure 2 / figure 3) to see photos!

      • Re: (Score:2)

        by Joebert ( 946227 )
        Everyone of those photos has something on still water just like it would be in a lab. As the part of my comment after the comma suggests, I want to know if it works where the water has a turbulent surface, like the surface of water in most places this would seem usefull, like shipping channels and whatnot.

        • Re:Calm water (Score:4, Insightful)

          by TapeCutter ( 624760 ) on Thursday January 22, 2009 @02:05AM (#26557127) Journal
          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?

          • Re: (Score:2)

            by dargaud ( 518470 )

            Can it drive a semi-submerged fishing trawler 30 feet up at about a 15-20deg incline

            Woah! You found a place with slopping waters ?!? That's awesome, now I can go waterskiing without the need for a boat !

          • You might rather use this [popsci.com] if you've got reliable waves.

        • Re:Calm water (Score:5, Interesting)

          by pato101 ( 851725 ) on Thursday January 22, 2009 @03:48AM (#26557571) Journal
          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).

        • Re:Calm water (Score:4, Interesting)

          by WindBourne ( 631190 ) on Thursday January 22, 2009 @05:29AM (#26557917) Journal
          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.

      • Re: (Score:3, Funny)

        by Q-Hack! ( 37846 ) *

        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 [mit.edu] the pics (search for figure 2 / figure 3) to see photos!

        I love how Figure #9 has the naughty bits blacked out!

         

    • Maybe not an ocean, but I've seen plenty of lakes that have glass-like calm.

    • Re: (Score:2)

      by rachit ( 163465 )

      Yes, there is a video of it being tested on the Hudson river here on YouTube [youtube.com]

    • Re: (Score:3, Informative)

      by b4upoo ( 166390 )

      There already exists a simple device that can power boats if there is wave action. In essence a pendulum is hooked to something that reminds one of a large swim fin. The swinging of the pendulum, due to wave action, move a mechanical ankle which holds the fin. It works well but it is obvious that this is for slow speeds only.

  • There is however one down side. (Score:3, Funny)

    by Anonymous Coward on Wednesday January 21, 2009 @11:51PM (#26556453)

    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.

  • Better Article (Score:5, Informative)

    by Selanit ( 192811 ) on Wednesday January 21, 2009 @11:51PM (#26556455)

    The New Scientist article [newscientist.com] 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.

    • Re:Better Article (Score:4, Informative)

      by arth1 ( 260657 ) on Wednesday January 21, 2009 @11:58PM (#26556509) Homepage Journal

      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.

      • 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.

        It doesn't matter how much of an effect it has.
        What matters is the cost* vs benefit of installing the gear.

        *Keeping in mind that the service life of these big ships is measured in decades, so the payoff doesn't have to happen in 4~5 years.

      • Re:Better Article (Score:5, Funny)

        by YourExperiment ( 1081089 ) on Thursday January 22, 2009 @07:11AM (#26558287)

        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.

    • 'Tis not science, I tell you, 'tis the result of congress with Lucifer!

  • Giant bottle of dishwashing liquid? (Score:2, Informative)

    by Anonymous Coward

    I built a boat like this when i was in grade 3.

    http://pbskids.org/zoom/activities/phenom/soappoweredboat.html [pbskids.org]

  • Glittering diamond of hope *cough cough* (Score:4, Funny)

    by Oricalchos ( 1339065 ) <lynx99@NosPaM.gmail.com> on Wednesday January 21, 2009 @11:52PM (#26556461)
    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.

  • primary school chemistry, anyone? (Score:5, Insightful)

    by arth1 ( 260657 ) on Wednesday January 21, 2009 @11:52PM (#26556463) Homepage Journal

    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.

  • for real (Score:3, Insightful)

    by hottoh ( 540941 ) on Wednesday January 21, 2009 @11:57PM (#26556485)

    The challenge is going to be scaling the technology from a "2cm" boat to something useful.

    It is fairly obvious how a bug moves about on the surface of still water, but the article says boats or small aquatic objects. A boat requires a lot of power to move against waves, wind and ocean currents.

    Am I alone in imagining water surface tension is never going to be enough to overcome the resistances to the forces found on our oceans?

    • Re: (Score:3, Funny)

      by Anonymous Coward

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

    • Re: (Score:2)

      by jd ( 1658 )

      Full-sized boats, yes. Surface-tension isn't going to be nearly strong enough. Useful boats - depends on the use. You can build very small robotic probes, and a robot submersible that can replace a motor and motor fuel with additional sensors and additional extra data storage is definitely going to be useful to a lot of marine biologists.

      It's going to be just as useful if Arthur C. Clarke ever lets a probe land on Europa, as lower overheads and superior data collection could make or break any mission sent t

      • Re: (Score:3, Insightful)

        by roguetrick ( 1147853 )

        Now I might not be one of dem scientist types as such, but I reckon that a boat that uses surface tension for propulsion wouldn't be too much of a submersible.

        • Re: (Score:2)

          by jd ( 1658 )

          Depends. If you're hunting round undersea volcanoes (plenty of gas bubbles), hang around toothed whales (who use air bubbles to trap prey underwater), or merely want to get your submersible from wherever you can park your ship to a more appropriate X/Y location on the surface of the ocean, I can see ways you could use surface tension.

          Or you could just theorise that I'm way down on sleep and am rambling incoherently with the occasional effort to sound somewhat sane.

  • This is why I've stopped RTQA. I was really hoping the boat would be propelled by the power of positive thinking. Surface tension?! Bor...ing... Although, 100 times efficiency is quite exciting. Would the efficiency scale though?

  • Never very practical (Score:3, Interesting)

    by Anonymous Coward on Thursday January 22, 2009 @12:02AM (#26556543)

    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.

    • The problem was it only was able to hit a couple of miles an hours inspite of the massive magnetic field.

      The other problem was that if it came too close to another ship, they stuck together.

  • What if there's sharks? What if I haven't eaten enough egg and baked beans? Besides wouldn't that make ME the engine?

  • RTFA (Score:3, Informative)

    by Anonymous Coward on Thursday January 22, 2009 @12:10AM (#26556609)

    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.

  • Boat moves without engine, paddles or sails (Score:5, Funny)

    by MichaelTheDrummer ( 1130657 ) on Thursday January 22, 2009 @12:16AM (#26556653)
    commonly known as 'drifting'

    • Re: (Score:2)

      by paul248 ( 536459 )

      commonly known as 'drifting'

      ... into the D-dimension! [youtube.com]

    • Re: (Score:3, Insightful)

      by radtea ( 464814 )

      commonly known as 'drifting'

      It's also false in the case at hand. The boat doesn't have a screw propeller but it does have an engine, which is electro-magnetic and acts on surface tension. This is like saying an electric car doesn't have an engine. Catchy, misleading and perfect for a /. headline.

    • Re: (Score:2)

      by Kismet ( 13199 )

      Yes: News flash! Corked bottle moves without engine, paddles or sails!

    • They could also make what I call a "whale chariot."

  •   Doesn't have a preferred vector. Newton still applies.

      SB

  • Yes but.. (Score:5, Funny)

    by Reed Solomon ( 897367 ) on Thursday January 22, 2009 @12:33AM (#26556725) Homepage

    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.

    • Forget about killing manatees. Is there some way that we can use this technology to send a probe to Jupiter's moon Europa and destroy any unique life that might have evolved in its subsurface ocean?

    • Re: (Score:2, Funny)

      by Anonymous Coward

      How effective is it at killing Manatees,

      Oh, the huge Manatee!

  • little slow? (Score:4, Insightful)

    by Tree131 ( 643930 ) on Thursday January 22, 2009 @12:41AM (#26556769)

    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.

    • The demo boat was 2 centimeters long and was navigating a small dish of water. I think their bigger concern with this proof-of-concept was not to make it as fast as possible but to prove it's a sound concept. Speed improvements will probably be more of a matter of how much energy you want to use to run such a vessel than technological improvements.

      • Re:little slow? (Score:4, Insightful)

        by eggnoglatte ( 1047660 ) on Thursday January 22, 2009 @02:30AM (#26557229)

        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.

        • Re: (Score:2)

          by haeger ( 85819 )

          Yes, but what if you could use this technology on regular ships and have them cut fuel consumption 10-20%? I'd say most shipping companies would like that.

          Haeger

  • Boat Moves Without an Engine Or Sails

    the vikings fixed this problem long ago.

  • "glide through the water without the need for an engine, sails or paddles"

    Humbug! Don't believe it. It's all wind in sails. ;)

  • In TFV in TFA, it looks more like there is some metal sheet in the bottom of the tank which is obviously the opposite electrode. Which makes me wonder if this is really that practical - would there be any net propulsive with both electrodes on the vessel?

    Due to the nature of surface tension I don't see this also scaling up to well, beyond something insect sized. I also wonder about efficiency, which may not beat a spinning propeller.

    There have already been wave-powered boats powered by vertical motion

  • The tinfoil hat wearing members of PETA won't stand for such sea kitten torture and distress!

  • Incongruities (Score:2, Interesting)

    by acidreverb ( 1339035 )
    Did anyone else find the copper sheet at the bottom of the water odd? Is that necessary to the device's operation? Would you always have to have a static component for something like this to work?

    Also, the "boat" didn't seem to have a power source, the electrodes appeared to be attached only to each other.

    The article seems rather bereft of information other than comparing the electrodes to a beetle larva. Does anyone understand how this device works? Outside of vague notions of something to do with
  • Instead of putting electrodes on the back of a boat to speed it up, perhaps they could put them on the front of a boat. This would slow the boat down a bit, but in theory breaking the surface tension in front of the boat could decrease the drag of the boat as it cuts through the water. I have no idea if this would improve efficiency, reduce it, or break even, but it would be an interesting experiment to try on larger boats.

Slashdot Top Deals

Whoever dies with the most toys wins.

Close