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Submersible Glider Powered By Thermal Changes

kdawson posted more than 6 years ago | from the kicking-the-battery-habit dept.

Robotics 72

An anonymous reader writes about a new robot submersible that uses temperature differences in the sea to power operation for more than twice as long as previous, battery-dependent vehicles. "The torpedo-shaped glider moves through the ocean by changing its buoyancy to dive and surface, unlike motorized, propeller-driven undersea vehicles. To power its propulsion, the submersible gathers thermal energy from the ocean. When it moves from cooler water to warmer areas, internal tubes of wax are heated up and expand, pushing out the gas in surrounding tanks and increasing its pressure. The compressed gas stores potential energy, like a squeezed spring, that can be used to power the vehicle. To rise, oil is pushed from inside the vehicle to external bladders, thus increasing the glider's volume without changing its mass, making it less dense. The oil can be shifted inside to increase the density and sink the vehicle."

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They should send a thousand of them to antarctica (1)

Loibisch (964797) | more than 6 years ago | (#22389968)

...to counter the melting ice-caps.

Re:They should send a thousand of them to antarcti (4, Funny)

RuBLed (995686) | more than 6 years ago | (#22390014)

That would be misinterpreted by the whales as an act of war...

So then would you call it... (0)

Anonymous Coward | more than 6 years ago | (#22390320)

I poasted on slashdot! O shi~

Re:They should send a thousand of them to antarcti (1)

SQLGuru (980662) | more than 6 years ago | (#22390670)

That would be misinterpreted by the whales as an act of war...
The whales? Screw them, I'd be more worried about the friggin sharks.....with lasers!

Layne

I've got it deployed against the greenhouse effect (4, Interesting)

MancunianMaskMan (701642) | more than 6 years ago | (#22390132)

and it works brilliantly. Mind, it's not a submersible so it's not quite so cool. it's just a device [greenhousemegastore.com] that opens the window in my greenhouse so that the tomatoes don't get too hot in the summer!

New problem, same root cause (4, Interesting)

CarpetShark (865376) | more than 6 years ago | (#22391016)

They should send a thousand of them to antarctica...to counter the melting ice-caps.


I assume you're getting at the same thing that I'm wondering... how much of an impact does this have on water temperature, currents, etc., if they're trying to call it "green"?

Of course, "green" doesn't mean much, but energy is never free, and taking it from an ecosystem is always going to have consequences.

In this case, we could try to use these, make them popular, and find out that they not only take heat energy from the oceans, but also change currents.

Likewise, we could try to cool the ice-caps somehow, but that wouldn't "counteract" what's happening with global warming; it would a more volatility to the system, with more extreme cold in one place battling more extreme heat elsewhere. The weather system is already too screwed up as it is without that.

And that's the REAL problem with this AND global warming: that we take things, on a massive scale, without any real respect for the damage it causes, or the slow processes that are needed to create what we take quickly. We can barely admit that we're doing damage, let alone facing the fact that the damage cannot be undone easily.

I'm not saying that we shouldn't use wind power, or solar power, or thermal power, or even combustion engines. BUT, we need to every bit of energy we take from the world -- in WHATEVER form -- depletes it, and that the only real solution is to cut back on how much we take.

Re:New problem, same root cause (2, Informative)

jim.hansson (1181963) | more than 6 years ago | (#22391240)

I'm not saying that we shouldn't use wind power, or solar power, or thermal power, or even combustion engines. BUT, we need to every bit of energy we take from the world -- in WHATEVER form -- depletes it, and that the only real solution is to cut back on how much we take.
NO, wrong, transform maybe, but depletes totally wrong

Re:New problem, same root cause (1)

CarpetShark (865376) | more than 6 years ago | (#22393244)

For all intents and purposes, it's depleted, if we can't put it back the way we found it, as quickly as we take away.

Re:New problem, same root cause (0)

Anonymous Coward | more than 6 years ago | (#22394448)

In the case of wind power we -are- putting it back the way we found it. And that's unfortunate.

Thermal energy provided by the sun causes mechanical disturbance in the atmosphere. The turbine harvests the mechanical energy, then converts it to electromagnetic. Which is then converted back into mechanical by the machines on the other end.

Discounting the materials production, our ultimate byproduct is thermal radiation from from the machines using the energy.

The only waste is in RF leak from the power lines and devices. The rest goes right back into the atmosphere as heat.

The sub works the same way: using thermal gradients to convert heat energy into mechanical energy, which then becomes heat again.

Considering that global warming is our Big Issue, we'd -want-to be "wasting" this thermal energy somehow. Sadly, we aren't.

Re:New problem, same root cause (1)

CarpetShark (865376) | more than 6 years ago | (#22421812)

Sounds about right, as far as it goes. But isn't the real problem that we drill energy from under ground, and release it into the atmosphere, with no way to put it back?

Uh.... (1)

maz2331 (1104901) | more than 6 years ago | (#22398632)

Do you have any idea just how BIG the oceans are and how much energy you need to remove to change the temerature by even a measurable amount?

Even the global warming argument is based on a change of under 1 degree and is far from settled.

Re:New problem, same root cause (1)

Dutch Gun (899105) | more than 6 years ago | (#22398866)

I'm not saying that we shouldn't use wind power, or solar power, or thermal power, or even combustion engines. BUT, we need to every bit of energy we take from the world -- in WHATEVER form -- depletes it, and that the only real solution is to cut back on how much we take.
Technically speaking, you're correct, but talking of "depleting" wind, solar, or thermal power is not really an issue. These forms of energy are already depleting (wind is essentially another form of solar power, if you get right down to it). Both the earth and sun are radiating an unbelievable amount of energy, whether we collect it or not. Depletion is really only an issue, practically speaking, when it comes to natural resources used to generate power. As such, it only makes sense regarding combustion engines, and only then when the fuel being used is non-renewable.

Regarding calling it "green", it's a silly buzzword that's overused today because the environment is a hot topic. It's a different way of saying they've found a way of extending it's operation life (i.e. it uses less power).

Re:New problem, same root cause (1)

MrKaos (858439) | more than 6 years ago | (#22401244)

Of course, "green" doesn't mean much, but energy is never free, and taking it from an ecosystem is always going to have consequences.
The problem is that currently we are using solar energy from the past stored in the form of coal and oil. Essentially duplicating those pre-historic conditions, when the atmosphere was more carbon rich, into the present.

In this case, we could try to use these, make them popular, and find out that they not only take heat energy from the oceans, but also change currents.
We already have, ocean currents have already had periods where they have shut down. This is a serious development as the mixing of currents and nutrients in the ocean is not only responsible for maintaining the food chain, but the algae that makes most of the breathable oxygen in the world. We are in an incident pit [wrolf.net] and the sooner we take steps to mitigate the situation by finding an energy balance the less difficult it will be for us all.

Re:They should send a thousand of them to antarcti (0)

Anonymous Coward | more than 6 years ago | (#22393588)

I assume you are just trying to be funny, but we could really use is something like this in Antarctica. It's really hard to study what is happening underneath the Antarctic ice sheets. You can't get a ship in for sonar, because of the ice. You can't get radio waves through the sea water, so airborne radar is out. So one of the most critical locations, where the sea water interacts with grounded ice, can only be studied by people on the ground. This is slow and dangerous (lots of crevasses). Getting a submersible up into that area to make measurements could drastically help our understanding of the interaction between sea water and ice. Even the most rabid anti-environmentalist should know that making accurate predictions about the future of sea level is important to the economy and even the oil industry need accurate forecasts and has started taking global warming seriously.

I been told very little is known about the deep oceans and the currents are very hard to monitor and map. Ocean monitoring (other than the surface) is incredibly sparse, since it's a 3D problem. As our planets goes through rapid changes, it would be nice to get an idea what this slow moving system is doing, it has to potential to sink large amounts of CO2 and heat, but not forever, and the heat makes the water expand.

Is this new? Still, cool stuff... (2, Interesting)

Dutch Gun (899105) | more than 6 years ago | (#22389994)

Call me crazy, but I thought I remembered seeing something like this on the Discovery Channel (or somewhere on cable) a year or two ago... It's a pretty clever device, using the up and down motion to propel itself forward through the water for a reduced energy expenditure. Still, I'll bet they have a ways to go before these things can safely navigate the real hazards of long-term ocean research (I wish the article had working links to more info). Power consumption is a big part of that, but I'd imagine there's a lot of other stuff that can go wrong. The ocean is a pretty unforgiving environment for machines of any sort.

"Call Me Crazy" (2, Funny)

AndGodSed (968378) | more than 6 years ago | (#22390046)

You're crazy.

Re:Is this new? Still, cool stuff... (0)

Anonymous Coward | more than 6 years ago | (#22390602)

Sperm whales use their wax in an energy conserving way too, for buoyancy and heat recovery.

Re:Is this new? Still, cool stuff... (0)

Anonymous Coward | more than 6 years ago | (#22390756)

hehehe you said "sperm"

Re:Is this new? Still, cool stuff... (1)

lawaetf1 (613291) | more than 6 years ago | (#22393794)

This is not new. I remember watching a show about this in HIGH SCHOOL. That was over ten years ago. Using the ocean's thermocline to change buoyancy and thereby achieve movement is an old idea.

Thermal insulation (1)

William Robinson (875390) | more than 6 years ago | (#22390034)

TFA does not mention whether it stores energy in 'thermal' form itself or uses the thermal waves to get energy and store in some other form, later case being most probable.

The Mighty Wiki already has an article about this (0)

Anonymous Coward | more than 6 years ago | (#22390372)

I didn't eat that fuckin sandwitch or the toielet thing either!

Re:Thermal insulation (1)

somersault (912633) | more than 6 years ago | (#22390518)

Uh.. the summary mentions that the heat causes wax to expand, so I'd have thought the article does the same. But yes it means that the energy is stored as pressure rather than storing the heat (which I'd think would be grossly inefficient).

When it moves from cooler water to warmer areas, internal tubes of wax are heated up and expand, pushing out the gas in surrounding tanks and increasing its pressure. The compressed gas stores potential energy, like a squeezed spring, that can be used to power the vehicle

Wait... what? (1)

Khyber (864651) | more than 6 years ago | (#22390040)

"The torpedo-shaped glider moves through the ocean by changing its buoyancy to dive and surface, unlike motorized, propeller-driven undersea vehicles"

Last I checked submarines had air tanks for buoyancy control, and newer subs are not motorized, but nuclear-powered. Something change in the past few hours while I was sleeping?

Re:Wait... what? (3, Informative)

MichaelSmith (789609) | more than 6 years ago | (#22390078)

Last I checked submarines had air tanks for buoyancy control, and newer subs are not motorized, but nuclear-powered. Something change in the past few hours while I was sleeping?

Submarines don't use changes in depth to push them horizontally. This device is a bit like a sailplane.

Re:Wait... what? (2, Interesting)

arivanov (12034) | more than 6 years ago | (#22390406)

It is spelled GLIDER. G L I D E R

On a more serious note gliding or "flying" under water as means of improving fuel efficiency and maneuvrability are not new. Research has been going on this since the 60-es. None of it has produced anything particularly spectacular.

Neat design, though there is a simpler way to do it. Put some solars on the glider, charge it on the surface, after that use the energy to compress the air used to expell the ballast tank. Sink. Reach target depth (gliding). Spew out ballast the same way a submarine does. Float up. Gliding. Sit on the surface while charging for another dive.

Trivial to do. No need for complex thermal stuff and you can probably survey half of the Pacific at a leasurely pace on one run until your batteries run out of charge cycles. This type of kit needs to float to the surface to transmit data back to base anyway, so why not do something productive in the meantime.

Re:Wait... what? (0)

Anonymous Coward | more than 6 years ago | (#22391764)

Trivial to do.

Well, dude, if it's that simple, what the hell are you waiting for? The submersible in the article probably represents a few million dollar's worth of effort for Wood's Hole. You could totally corner the market.

Re:Wait... what? (1)

TemporalBeing (803363) | more than 6 years ago | (#22392156)

It is spelled GLIDER. G L I D E R

On a more serious note gliding or "flying" under water as means of improving fuel efficiency and maneuvrability are not new. Research has been going on this since the 60-es. None of it has produced anything particularly spectacular.

Neat design, though there is a simpler way to do it. Put some solars on the glider, charge it on the surface, after that use the energy to compress the air used to expell the ballast tank. Sink. Reach target depth (gliding). Spew out ballast the same way a submarine does. Float up. Gliding. Sit on the surface while charging for another dive.

Trivial to do. No need for complex thermal stuff and you can probably survey half of the Pacific at a leasurely pace on one run until your batteries run out of charge cycles. This type of kit needs to float to the surface to transmit data back to base anyway, so why not do something productive in the meantime.
That would only work for limited dives; extended dives would be heavily dependent on your batteries and their ability to charge fast enough for your time on the water. Also, forget about any black-ops with such a design - for that you need to be under water as much as possible.

TFA's design is pretty cool and would work even for extended dives. Since it doesn't require surfacing black-ops are also possible. It could probably reach deeper depths, and longer periods at deeper depths would be a given.

That said, adding some solars might be useful to charge while its surfaced, but they shouldn't be required for the sub to work, which your proposed design would require.

Re:Wait... what? (1)

mapsjanhere (1130359) | more than 6 years ago | (#22392866)

So, let me get this straight, I remove the propellers that use energy and give the sub maneuverability and I use less energy? Brilliant concept, like a car that only uses a small battery to run the stereo but has no engine to waste gasoline. I just let the traffic push it along. I think I take a solar powered version that charges during the day and dives at night.

Re:Wait... what? (2, Insightful)

don depresor (1152631) | more than 6 years ago | (#22390408)

and newer subs are not motorized, but nuclear-powered. Excuse me but what do you think a nuclear reactor and a turbine are? If they had 100 guys pulling a lever that moved the propeller, then you could say that they aren't motorized ( and you could argue that they have an human motor anyway...). But saying that a nuclear sub isn't motorized...

Re:Wait... what? (2, Insightful)

Simon Brooke (45012) | more than 6 years ago | (#22390458)

"The torpedo-shaped glider moves through the ocean by changing its buoyancy to dive and surface, unlike motorized, propeller-driven undersea vehicles"

Last I checked submarines had air tanks for buoyancy control, and newer subs are not motorized, but nuclear-powered. Something change in the past few hours while I was sleeping?

And those 'newer subs' use a nuclear reactor to power - guess what? - a motor.

There was a time when the average slashdot user had more than two braincells to rub together, but that time seems sadly past.

Re:Wait... what? (4, Informative)

hcdejong (561314) | more than 6 years ago | (#22390554)

Last I checked submarines had air tanks for buoyancy control

The air tanks are used mainly used to switch between surface and submerged modes, for trimming (keeping the sub horizontal), and to compensate for changes in water density. Because the amount of lift generated by a body does not change much with its depth, the air tanks cannot provide fine control of your diving depth. Also, a naval sub prefers not to use the air tanks once submerged, because venting air leaves a trail on the surface.
For fine depth control, a sub uses its diveplanes: wing-like surfaces that provide lift (positive or negative) as long as the sub keeps its speed above a minimum.

In effect, this glider reverses the process: changes in buoyancy are used to generate an upwards/downwards force, which is converted by the wings into forward motion.

newer subs are not motorized, but nuclear-powered.

You mean some newer subs are nuclear-powered. Conventional-powered submarines are still being built today. Often, in addition to the traditional diesel engines, an air-independent propulsion system is installed, either a Stirling engine or a set of fuel cells.

This is SO COOL! (1)

AndGodSed (968378) | more than 6 years ago | (#22390062)

Things like these make the world sit up and realize that geeks and nerds have so much to contribute to society. Leave us to our pirated warez - we gave you teh Thermal Sub!

Sounds like the perfect drug-smuggling device. (2, Informative)

jcr (53032) | more than 6 years ago | (#22390070)

Just sayin'...

-jcr

Re:Sounds like the perfect drug-smuggling device. (2, Insightful)

MichaelSmith (789609) | more than 6 years ago | (#22390134)

I can't see it working well in shallow waters. I don't think it would have much scope for navigation either, as it spends most of its time at depth away from GPS signals.

For a drug mule you want something you can deploy and collect at a precise location on a beach, which for me, means a solar powered UAV which will sit just below the surface. Not that I have tried to build any such thing of course.

Human drug mules are cheaper anyway.

Re:Sounds like the perfect drug-smuggling device. (1)

jcr (53032) | more than 6 years ago | (#22390310)

I can't see it working well in shallow waters.

I'd say it depends on the temperature gradient more than the depth. Even 50' lakes can have a pretty significant temperature difference from the surface to the bottom.

-jcr

Re:Sounds like the perfect drug-smuggling device. (2, Insightful)

don depresor (1152631) | more than 6 years ago | (#22390450)

You know that nuclear subs have been traveling underwater for years before the existence of GPS tech, right?

You have things like inertial systems, the old magnetic compass, sonars that help you by telling you the features of the sea bottom (you know like the old age when you looked for a landmark you knew and used it to locate yourself) and other things...

Re:Sounds like the perfect drug-smuggling device. (0)

Anonymous Coward | more than 6 years ago | (#22393370)

You sir, while successfully pompous and arrogant, have completely and utterly failed to explain how any of these devices will help this little bugger smuggle drugs. Parent made a good point, the design of this thing seems to make it unlikely that you should be able to expect it in a certain place at a certain time, and yes it is inferred by parent that we're talking unmanned here.

Re:Sounds like the perfect drug-smuggling device. (0, Offtopic)

Whiney Mac Fanboy (963289) | more than 6 years ago | (#22390216)

*fingers crossed*

Re:Sounds like the perfect drug-smuggling device. (1)

merreborn (853723) | more than 6 years ago | (#22394364)

Sounds like the perfect drug-smuggling device.
It has a horizontal velocity of under 1 mph. I'd say that's a pretty major downside.

Re:Sounds like the perfect drug-smuggling device. (1)

jcr (53032) | more than 6 years ago | (#22397764)

That may not matter, if you have a steady supply. The win would be that detection would be difficult due to the size, and interception at sea wouldn't risk the capture of the smugglers.

-jcr

Vaporware tag seems unjustifed (2, Insightful)

sapphire wyvern (1153271) | more than 6 years ago | (#22390180)

Built by the Webb Research Corporation in Falmouth, Mass., the new submersible has successfully traveled back and forth between two of the U.S. Virgin Islands, St. Thomas and St. Croix, more than 20 times. WHOI researchers plan to use the data gathered by the craft to study ocean currents in the area.
Since when is something that physically exists and has been tested in the field vaporware?

Re:Vaporware tag seems unjustifed (1)

WhyMeWorry (982235) | more than 6 years ago | (#22390256)

Hint: this is slashdot. The summary doesn't mention the test trials therefore the item doesn't exist.

Re:Vaporware tag seems unjustifed (1)

sapphire wyvern (1153271) | more than 6 years ago | (#22390306)

Oh well. At least the article doesn't have mention the word "bricked".

Re:Vaporware tag seems unjustifed (1)

CRCulver (715279) | more than 6 years ago | (#22390424)

I added that tag, continuing the tradition started by others of adding it to every article about new technology.

Re:Vaporware tag seems unjustifed (0)

Anonymous Coward | more than 6 years ago | (#22390648)

Why use the tagging system at all if you're just going to bitch it up?

reminds me of... (1)

catmistake (814204) | more than 6 years ago | (#22390190)

first post?
reminds me of Carl Sagan's fantasies about creatures on Jupiter... perhaps that inspired its conception

thevapowaretagisincorrect (4, Informative)

z0idberg (888892) | more than 6 years ago | (#22390198)

I know, I was shocked too, but the vaporware tag is wrong.

They have had one working that has traveled 1400 kms so far since launch in December. Better article here
http://www.cbc.ca/technology/story/2008/02/08/tech-glider-undersea.html [www.cbc.ca]

Perfect for Underwater Cables (5, Funny)

WallyDrinkBeer (1136165) | more than 6 years ago | (#22390260)

They've been testing it by cutting some cables, right?

I know this is impossible... (1, Interesting)

Anonymous Coward | more than 6 years ago | (#22390286)

...and that perpetual motion machines are bunk; but humor me.

Could someone show me why you couldn't use this method of adjusting boyancy to get more energy out than you put in?

Let's say you have your sub which is neutrally boyant at the surface. You pump oil out of the bladders. The sub drops. When the sub gets to the bottom, you pump your oil back into the bladders. The sub rises once more.

And let's say the drop is used generate electicity, via magnets or coils the sub falls past.

Now... Does the energy required for pumping the oil always equal the amount of energy which is generated by passing the sub past the coils? It does require more energy to pump the oil into the badders when the sub is on the ocean floor, due to the increase in pressure, but it seems odd to think that the amount of energy required to simply blow up a balloon is the same as whatever energy you could extract from it's rise into the straosphere, and its subsequent plummet back to earth.

Ask Newton. (1)

Comboman (895500) | more than 6 years ago | (#22391038)

Could someone show me why you couldn't use this method of adjusting boyancy to get more energy out than you put in?

First law of thermodynamics. The system you describe might work (probably very inefficiently) but it would not be getting more energy out than is put in. Every trip up and down would make the temperature of the ocean slightly more uniform; that's the energy loss to balance the energy being created.

Re:Ask Newton. (2, Informative)

zippthorne (748122) | more than 6 years ago | (#22395886)

No, the energy in that plan doesn't come from the sea temp, it comes from the ballast. The thing you're depleting is the available buoyancy material, whether it be helium, air, or oil.

For a closed-circuit buoyancy engine, you have to physically pump the buoyancy material around to get your change in density. This pumping is against whatever the ambient pressure is, so the deeper you allow it to drop, the more force you have to pump against to get your buoyancy back and return to the surface.

Since you have to pump the same volume of material either way, against a force that depends on the depth , it takes more work to get your buoyancy back the deeper you go. This works whether do the pumping on the bottom with oil-bladders, or at the top with air bladders.

That's nothing... (1)

wwalker98 (601563) | more than 6 years ago | (#22390314)

...I used to have a sub that was powered by baking soda.

Irritating first line of article though (4, Insightful)

Kupfernigk (1190345) | more than 6 years ago | (#22390436)

"Scientists have invented the Prius of ocean-going submersibles - a new "green" robotic glider that runs on energy absorbed from the heat of the sea, rather than batteries."

Scientists research, they discover, they do not invent. Engineers invent. Doesn't anybody in journalism know the difference between a scientist and an engineer? Also, the Prius is actually a bit like a conventional submarine - IC engine charges the batteries - and is therefore (from a marine engineering perspective) very old tech dating from before WW2. This on the other hand is seriously clever. In fact, it's like powering your car off a massive array of engine thermostats (which rely on wax as the operating means.) So a better lead in would be "Engineers have developed an energy efficient vehicle which is nothing whatever like a Prius - it uses temperature gradients in the sea to power itself."

Perhaps Microsoft deserves to take over Yahoo.

Re:Irritating first line of article though (1)

gardyloo (512791) | more than 6 years ago | (#22392270)

Wow. So if I, as a "scientist", do any research, and in the course of that research need to invent something new -- a new measurement process, a lens holder, some clever demodulation circuit -- that means that I am not a scientist? I am an engineer?

      Engineers research, discover, and do _science_. Scientists engineer.

Re:Irritating first line of article though (1)

merreborn (853723) | more than 6 years ago | (#22394314)

Irritating first line of article... Perhaps Microsoft deserves to take over Yahoo.
Yahoo! News rarely if ever posts anything written by Yahoo! employees. If they do have anyone writing exclusively for Yahoo! News, I've never seen it. In this case, the source is clearly identified by the logo that links to livescience.com and the tag at the top:

Clara Moskowitz
LiveScience Staff Writer
SPACE.com
So maybe Microsoft "deserves" to take over LiveScience.com...

Re:Irritating first line of article though (2, Insightful)

xPsi (851544) | more than 6 years ago | (#22402662)

Scientists research, they discover, they do not invent. Engineers invent. Doesn't anybody in journalism know the difference between a scientist and an engineer?
I'm guessing since you just invented that distinction you are an engineer then? Seriously, I know plenty of scientists and engineers who do a healthy mix of research, discovery, and invention. Science journalism may have other problems, but I don't think this is one of them.

Gliders don't need to be powered (2, Funny)

Schiphol (1168667) | more than 6 years ago | (#22390532)

Rather, gliders [wikipedia.org] travel in virtue of the laws of reality alone. And at a speed of c/4.

A reality check on this (1)

Ancient_Hacker (751168) | more than 6 years ago | (#22390556)

Er, um, there's quite a few problems with this concept:
  • The efficiency is very low. Whatever the temperature difference is between the inside and outside of the sub in degrees C, divide that by 273, that's the maximum possible efficiency. If you wait forever for the heat to transfer. And assuming there is a difference to exploit.
  • Your typical sub has like 10 to 80 thousand horsepower. This sub, on a good day, might do 2% of that. Not exactly a barn-burner. And not even enough to run the lights and air-conditioners.

Re:A reality check on this (2, Insightful)

chuckymonkey (1059244) | more than 6 years ago | (#22390638)

They never said that it had to carry people, and I bet it's a great research vessel since they have one working as a previous poster already said. Since it rides thermal currents in the ocean I think that you could put a GPS tracker in it and find some very good data about changing ocean currents, not to mention the vast amounts of other data you could gather with something like this that doesn't really need to refuel or resupply.

Re:A reality check on this (2, Funny)

rholland356 (466635) | more than 6 years ago | (#22394758)

Your typical sub has like 10 to 80 thousand horsepower. This sub, on a good day, might do 2% of that. Not exactly a barn-burner. And not even enough to run the lights and air-conditioners.

True that!

But given this is a robotic submersible, why does it need air conditioners and lights?

Re:A reality check on this (1)

Ancient_Hacker (751168) | more than 6 years ago | (#22398492)

>But given this is a robotic submersible, why does it need air conditioners and lights?

But it still needs to be able to move around. If it gets into a large area of homogenous water, like the Gulf Stream, what's it gonna do? Even in a perfect environment with steep thermal contrasts, I don't think it can buoyancy-glide it's way out of even a minor current. In the Gulf Stream, it's gonna flounder.

Re:A reality check on this (1)

rholland356 (466635) | more than 6 years ago | (#22425040)

>But given this is a robotic submersible, why does it need air conditioners and lights?
But it still needs to be able to move around. If it gets into a large area of homogenous water, like the Gulf Stream, what's it gonna do? Even in a perfect environment with steep thermal contrasts, I don't think it can buoyancy-glide it's way out of even a minor current. In the Gulf Stream, it's gonna flounder.


Egads! Are you saying this device was engineered without consideration for usage? What leads you to this conclusion?

Good for surface work (1, Informative)

Anonymous Coward | more than 6 years ago | (#22390572)

Its an interesting invention that will be great for near-surface work, but I guess it will not be a whole lot of use for deep exploration since temperatures remain pretty constant in deep ocean and if anything tends to get slightly colder with depth. But given its a hybrid perhaps you can burn the battery on the way down and use temperature increase on the way up :-)
Still and interesting piece of equipment. Research veseel time is very, very expensive, so if the cost of creating an autonomous vehicle coudl be kept relatively down and be given enough range to propel itself to areas of interest, this could be very useful both for science and other maritime work (like pipe/cable inspection).

This would have been brilliant in WWII (1)

dj42 (765300) | more than 6 years ago | (#22390634)

I can't see how modern day subs would have ANY interest in this. Seriously. You would have to modulate your path based on water temperature, and baby-jesus forbid, you are forced to transverse water the same temperature for a few months. This is useless technology unless WWIII starts tomorrow.

Re:This would have been brilliant in WWII (2, Informative)

esocid (946821) | more than 6 years ago | (#22392444)

I can't see how modern day subs would have ANY interest in this. Seriously. You would have to modulate your path based on water temperature, and baby-jesus forbid, you are forced to transverse water the same temperature for a few months. This is useless technology unless WWIII starts tomorrow.
You seem to be missing the point, or didn't RTFA. This is a science vessel that uses a hybrid battery/thermal powered propulsion and electronic system. This allows the research vessel to remain submerged longer than normal by not needing to rely completely on battery power.
Nice try though.

Can't patent it (1)

n3tcat (664243) | more than 6 years ago | (#22390948)

Politicians will claim prior art based on the fact that it's powered by a series of tubes.

By no means new (1)

g0bshiTe (596213) | more than 6 years ago | (#22391558)

I saw this more than 5 years ago on Discovery Channel.

This just in (1)

Project2501a (801271) | more than 6 years ago | (#22391958)

Submersible CowboyNeal Powered by Linux Strikes at Soviet Russia.

AH! MOTHERLAND!

(vending from work)

This is an old idea from a "Daedalus" column (1)

mbg (28004) | more than 6 years ago | (#22401352)

The inventor David E. H. Jones, better known as Daedalus [wikipedia.org] , described a very similar underwater glider in one of his columns. From memory, his version exploited a liquid that changed volume with temperature, rather than a wax (and the temperature-volume relationship was in the opposite direction).

The column is included in the compilation "The Further Inventions of Daedalus" published in 1999. I think an early prototype of the wax-based mechanism (apparently an independent, though later, invention) had already appeared at the time of publication.

It's astounding how many of Daedalus' crackpot schemes later emerged as real inventions -- occurrences Jones documents with enthusiasm in the two compilations. One great example is the similarity between Daedalus' "Unisphere" and the much later Segway.

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