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Submersible Glider Powered By Thermal Changes
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."
...to counter the melting ice-caps.
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.
Irony: Agile development has too much intertia to be abandoned now.
That would be misinterpreted by the whales as an act of war...
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.
hilarious
"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?
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
You're crazy.
Seven Days with Ubuntu Unity
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!
Seven Days with Ubuntu Unity
Just sayin'...
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
and it works brilliantly. Mind, it's not a submersible so it's not quite so cool. it's just a device that opens the window in my greenhouse so that the tomatoes don't get too hot in the summer!
first post?
reminds me of Carl Sagan's fantasies about creatures on Jupiter... perhaps that inspired its conception
The Admin and the Engineer
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
They've been testing it by cutting some cables, right?
...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.
...I used to have a sub that was powered by baking soda.
I poasted on slashdot! O shi~
I didn't eat that fuckin sandwitch or the toielet thing either!
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.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Rather, gliders travel in virtue of the laws of reality alone. And at a speed of c/4.
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).
Sperm whales use their wax in an energy conserving way too, for buoyancy and heat recovery.
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.
We are one consciousness experiencing itself subjectively. Back to you with the weather, Bob!
Layne
Further details on the glider from the designer's web site: http://www.webbresearch.com/thermal_glider.htm
hehehe you said "sperm"
Here's an article written in 2005 about these things: Underwater Robot to Re-Cross Gulf Stream
Politicians will claim prior art based on the fact that it's powered by a series of tubes.
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.
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.
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I saw this more than 5 years ago on Discovery Channel.
I am Bennett Haselton! I am Bennett Haselton!
Submersible CowboyNeal Powered by Linux Strikes at Soviet Russia.
AH! MOTHERLAND!
(vending from work)
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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.
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.
CommentBot 0.7a running with args "-module irritate,disagree -target random"
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.
The inventor David E. H. Jones, better known as Daedalus, 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.