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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."
*eom*
Dedicated Cthulhu Cultist since 4523 BC.
If they ever make that feasible for passenger boats then the passsengers better bring the Dramamine.
Do you have battletoads?
Yeah, but does it run Linux?
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.
it's easy to make a boat move without engine or sails. just put it on top of some waves or something.
Can this really work outside of a lab, where the water surface isn't like glass ?
Wanna fight ? Bend over, stick your head up your ass, and fight for air.
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.
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.
I built a boat like this when i was in grade 3.
http://pbskids.org/zoom/activities/phenom/soappoweredboat.html
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.
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.
So this works if yo are a 2 cm boat (that just wants to spin, apparently) or an insect.
Lots of things that work great for insects don't scale up well. That's why you only see insects using them. Pretty boring. You'll never see thing on a large boat.
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?
Anonymous Coward here, If this technology is so great, why doesn't my house run on it, or why doesn't the government fund it, this is nothing more than a hoax on all of us, you ought to be ashamed!
whoohoo, 2 mm per second! Hold onto your hat!
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?
EvilCON - Made Famous by
We did something similar but on a tiny scale when we were kids. Take a model boat hull and stick a small soap piece to it at the back such that at least some part of it sticks out below the water line. Place the whole thing in still water and the desolving soap provides the forward thrust for the hull. I believe this is due to the difference in surface tension of soap water and the surrounding water.
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.
What if there's sharks? What if I haven't eaten enough egg and baked beans? Besides wouldn't that make ME the engine?
These posts express my own personal views, not those of my employer
I had a look at their article and I think they
misunderstood the effect they are seeing. They
seem to think just through having a voltage
statically applied to the back plate and making
the back plate "wetted" they can generate a force. This clearly isn't the case in the steady state (would break conservation of energy, if the boat was moving, if you assume it's just the wetting effect because that provides no work). It seems they are applying a very high voltage (160V) which may be propelling the boat by effects like heat or vaporization, etc. There may be ways to use effects like wetting to propel a boat but I don't think these researchers have found those ways.
I'm hydrophobic. Like a lipid's tail. WHAT TO DO?
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.
commonly known as 'drifting'
Next up, a frigate powered by pure sexual tension!
Doesn't have a preferred vector. Newton still applies.
SB
It's old. The more humans I meet, the more I like my cats. At least they are honest.
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.
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!
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.
Let's see; small insects have been doing this for millions of years, one would think. Seems somewhat evolutionarily advantageous. I bet it would come in handy for larger creatures. So where are they? Even guy in link merely floats and flagellates:
http://en.wikipedia.org/wiki/File:Agkistrodonpconanti1.jpg
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.
... yup, a nice shiny bridge that has moving water under it. You could put in a hydro turbine or two.
Ok, we need to see some real hard data on this phenomenon to ensure it's real and can be scaled.
They can start by showing the details of how to reproduce this exactly.
So they invented oars?
As if Hypno-toad wasn't bad enough... now we have Robo-duck?
corp. mouthpieces said they wanted to "improve" on the technology. Stay tuned in about 2350.
...the comments on the page say it all. Scroll down... then sink this article
could be powered by batteries, radio waves, or solar power
Or wave power! like the Google data centers!
So basically, if you ever wanted to transport people with this, they'd have to be smaller than Lego figures? Move on, nothing to see here...
There are two rules for success:
1. Never tell everything you know.
Mod sibling up
"glide through the water without the need for an engine, sails or paddles"
Humbug! Don't believe it. It's all wind in sails. ;)
It was powered by bicarbonate of soda. Went round the bath a treat.
I, for one, welcome our new Hunt-for-Red-October overlords!
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, that have been sucessfully shown to work - no egines or sails - especially well in a head wind!.
http://www.popularmechanics.com/technology/transportation/4254404.html
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
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.
Reminds me of Steam Candle
It pays to be obvious, especially if you have a reputation for being subtle.
... soap factory shares have soared.
Can it be powered by a wind turbine?
Here's the math and a nice picture (page 4):
http://web.mit.edu/1.63/www/Lec-notes/Surfacetension/Lecture4.pdf
"Boat Moves Without an Engine Or Sails"
I'd have to answer that one with "What is rowing?"
Many years ago, while I was still active in scientific research, I was fascinated by the world's propensity to innocently re-discover old ideas, albeit usually with a new technological twist. Almost all forms of directed biological locomotion consist fundamentally of a series of repeated attachment and detachment events, which can sometimes be regular enough to become a wave or an oscillation. Whether you consider walking with legs, amoeboid movement, gliding bacteria, snails, snakes, flapping wings, etc, the basic logic holds. It even extends beyond the mechanics into command and control: chemotaxis and nervous signalling are just developments of the basic process. When I stuck my oar into that field it really only amounted to giving a new twist to an old idea and it was amusing to see just how many people continued to either proclaim that related phenomena were not understood or else to rediscover the answer from scratch.
In this particular case, to make a viable propulsion system it will be necessary to oscillate the electrical field and propagate it along the sides of any vessel. In that case, the attainable speed and efficiency will depend upon the degree of change in 'stickiness' to the surrounding water that can be achieved and the surface area of the 'boat'. I would expect this new scheme to work best on small boats. Most biological systems that work this way rely on an interface, with a solid or the air. So thrust will scale as the first or second power of length, while load capacity scales as the third power.
How can we be expected to teach children to learn how to fish if they can't even fit inside the boat?
I've been in some places where water have a perfectly vertical slope, without the need of waves.
Of course, I wouldn't like to surf there...
Rethinking email
It seems figure 9 required some editing to protect the children..
+ An opinion should be the result of thought, not a substitute for it. +
Comment removed based on user account deletion
Hold up, if I am not mistaken isnt one of the definitions of engine: A machine that converts energy into mechanical force or motion. So that just leaves drifting with the wind or current. I think a sail might be mutch more practical.
sorry for my comments, I'm drunk
The tinfoil hat wearing members of PETA won't stand for such sea kitten torture and distress!
-tyfighter
It moves only vertically...............
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 surface tension that is.
"No matter how cynical you get, it is impossible to keep up." -- Lily Tomlin
No emissions, but it electrocutes all the fish around it....
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?
'Tis not science, I tell you, 'tis the result of congress with Lucifer!
SJW: Someone who has run out of real oppression, and has to fake it.
On this page, there are mating water striders, and they've blocked out their eyes to protect their identities. Moderately funny.
Actually, there is no boat. Only the technology.
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.
Move the water!
This is nothing new. I've been making boats like this since I was a kid. All it takes is a calm pond with pine trees growing nearby.
Take a matchstick sized dry twig. Find a pine tree that's oozing sap from a scratch in the bark or a broken branch/twig. The sap should have the viscosity of syrup. Dip one end of the dry twig in the pine sap, bringing up a tear drop-sized dollop of sap. Drop your highly-advanced research vessel in a nearby pond and watch it put-put around for a good minute or so before all the sap is gone or it gets stuck in its own sap trail.
Thinking about it, you could probably do this at home with an actual match stick and some pancake syrup. It's just always been an outdoor sort of thing for me.
Sorry, you're just wrong. Haven't you ever heard of User Mode Linux? There's plenty of tension there, and not just on the surface! Just ask any User trying to install a new distro for the first time.
I read an article in New Scientist about this and was confused about the mechanism described. The networkworld article linked to in the summary is slightly better because in talks about an electric pulse, implying that it's not steady state.
It sounds like the there is an electrode on the back on the boat, and when a potential is applied to that electrode it changes the surface from hydrophobic to hydrophilic. This change causes the boat to tilt in the water and it is propelled slightly forward. The potential is then turned off, the boat relaxes to a flat position, the potential is turned back on again, and so on. The net result is a forward motion.
The main advantage won't be efficiency but rather it is a mechanism well suited to very small boats where surface tension is relatively much more important.
"...an electrode attached to a 2-centimeter-long "mini-boat" emitted a surge that changed the rear surface tension direction and propelled the boat at roughly 4 millimeters per second."
Sea slugs rev your engines!
Read the article more thoroughly. The wikipedia article mentions water only a few times, chief among them: "MagnetoHydroDynamics ... studies the dynamics of electrically conducting fluids. Examples of such fluids include plasmas, liquid metals, and salt water."
The other mentions of water and seawater contrast it with more ideal materials, rather than comparing them favorably.
To the best of my knowledge, nobody has managed to create usable thrust by directly affecting seawater via MHD. Rather, a magnetic slurry is driven by MHD, which in turn pushes water, exactly as I stated. I did NOT state that seawater was unaffected by MHD. What I stated was that known physical drives that use MHD, do so indirectly via a contained ferromagnetic fluid.
as mentioned in the very article you cite, nobody has managed to make a practical "drive" using those means. They have come much closer to practicality using methods such as I have described.
An IDEAL MHD drive would not need an intermediary mechanical stage... but so far, none have been practical without it.
If you can cite a pure MHD drive that works better than those that use a magnetic slurry as an intermediate stage, by all means do so.
...Of mithril and of elven-glass
With shining prow; no shaven oar
Nor sail she bore on silver mast...
What of the pulses' effects on marine life?
"...low-energy electrode that emits the pulse..."
We'll need at least a few hundred years of study and legal injunctions.