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Underwater Robot Powered By Ocean's Thermal Energy

Soulskill posted more than 4 years ago | from the maybe-skynet-evolves-from-the-seas dept.

Robotics 40

separsons writes "A team of scientists recently created the world's first underwater robotic vehicle powered entirely by renewable ocean thermal energy. Researchers from NASA, the Scripps Institution of Oceanography and the US Navy developed Sounding Oceanographic Lagrangrian Observer Thermal RECharging (SOLO-TREC), an autonomous robot that runs on a thermal recharging engine. The engine derives power from the natural temperature differences found at varying ocean depths. SOLO-TREC produces about 1.7 watts of power each dive, enough to juice the robot's science instruments, GPS receiver, communication device, and buoyancy control pump. SOLO-TREC is poised to revolutionize ocean monitoring; previous robots could spend only a limited amount of time underwater because of depleting power sources. SOLO-TREC can stay beneath the surface of the waves for indefinite amounts of time. Based on SOLO-TREC's success, NASA and the US Navy plan to incorporate thermal recharging engines in next-generation submersibles."

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1.7 Watts of power each drive (0)

Anonymous Cowar (1608865) | more than 4 years ago | (#31799906)

Need .711 gigadives to make 1.21 gigawatts!

Now does it hit 88mph?

Re:1.7 Watts of power each drive (2, Funny)

Anonymous Coward | more than 4 years ago | (#31799952)

DeLoreans are submersible, but I don't think they ever make it back to the surface, so you'd better hit your 88 MPH on the way down.

Re:1.7 Watts of power each drive (1)

lobiusmoop (305328) | more than 4 years ago | (#31799964)

FTFA, it's 1.7 Watt-Hours (6100 Joules) generated, rather than 1.7 watts. It's still peanuts though really.

Re:1.7 Watts of power each drive (3, Insightful)

WrongSizeGlass (838941) | more than 4 years ago | (#31799976)

FTFA, it's 1.7 Watt-Hours (6100 Joules) generated, rather than 1.7 watts. It's still peanuts though really.

It true that 1.7 Watt Hours isn't much, but it doesn't need to be a lot, it just needs to be enough.

Re:1.7 Watts of power each drive (1)

goombah99 (560566) | more than 4 years ago | (#31800330)

I'm puzzled over the "per dive" part of this. this seems to imply it's that downward dive itself that is some how producing the energy. that is to say this energy is not continuously produced but would require another dive cycle to produce. So it' can't stay down. perhaps it can cycles dives autonomously?

And how is this power produced. I'm going to guess what is happening is that it comes up and warms up till it's core temperature is at the ambient surface temperature. Then it drops like a rock, and uses the heat differential between the core and the cold water to drive some thermo electric engine in reverse. perhaps they toss in some phase change material to extend the thermal capacity.

or is it something different?

Re:1.7 Watts of power each drive (1)

FlyingGuy (989135) | more than 4 years ago | (#31800428)

My SWAG ( Sonarmans Wild Ass Guess) is that it has to repeatedly move up and down through the water column. One you are past the main thermocline the ocean is a pretty constant temp. It might be based on sterling or something like that.

Re:1.7 Watts of power each drive (4, Informative)

Iron Condor (964856) | more than 4 years ago | (#31800706)

And how is this power produced. I'm going to guess what is happening is that it comes up and warms up till it's core temperature is at the ambient surface temperature. Then it drops like a rock, and uses the heat differential between the core and the cold water to drive some thermo electric engine in reverse. perhaps they toss in some phase change material to extend the thermal capacity.

or is it something different?

Why not ask the people who built it? From http://solo-trec.jpl.nasa.gov/SOLO-TREC/ [nasa.gov] :

Special Phase Change Materials (PCMs) on-board the SOLO-TREC expand about 13% when heated above 10 degree Celsius and then correspondingly contract when cooled below 10 degree Celsius. This expansion/contraction produces a high pressure oil that can be collected and periodically released to drive a hydraulic motor for electricity generation and battery recharging. Since its deployment, SOLO-TREC has been making 3~4 dives per day between the surface and 500 meters depth, producing about 1.6 Watt-hours of power each dive to operate the on-board sensors, GPS receiver and communication device.

I'd like to add that JPL is of course the place to go to if you need to run gizmos for a long time on almost-no-energy input, reliably, in rather hostile environments. I mean - the Voyagers are still sending data home, 30+ years later , 100+ AU away and with a transmitter not much better than a modern cell phone...

Re:1.7 Watts of power each drive (1)

PolygamousRanchKid (1290638) | more than 4 years ago | (#31800100)

... Intel announces plans to ship systems equipped with an experimental 48-core CPU ... . According to Sean Koehl, technology evangelist with Intel Labs, the chip only draws between 25 and 125 Watts

Well, I guess this new sub won't have this Intel 48-core Gigantium Inside.

Error 503 Service Unavailable (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#31800152)

You fucking morons!! you people should have been drowned at birth! You are beyond useless! FUCK OFF!! and FIX IT GODDAMMIT!!!

Re:Error 503 Service Unavailable (0)

Anonymous Coward | more than 4 years ago | (#31800890)

Getting the same here, weird thing is I just got the exact same 503 on digg, guru meditation and all. Using CDN ISP ...

Go "further", more passive? (4, Interesting)

sznupi (719324) | more than 4 years ago | (#31799972)

I wonder...with the temperatures in the deep quite predictable, likewise at the surface in targeted time period and location, perhaps underwater glider with buoyancy control via passive mass having "weird" thermal expansion properties would be also feasible? Who knows if worthwhile though, with less precision and need for control pump anyway, for surfacing...

Re:Go "further", more passive? (0)

Anonymous Coward | more than 4 years ago | (#31800096)

I think the real question is: can I get an alarm clock powered by the currents in my waterbed?

Re:Go "further", more passive? (0)

Anonymous Coward | more than 4 years ago | (#31800202)

I wonder...with the temperatures in the deep quite predictable, likewise at the surface in targeted time period and location, perhaps underwater glider with buoyancy control via passive mass having "weird" thermal expansion properties would be also feasible? Who knows if worthwhile though, with less precision and need for control pump anyway, for surfacing...

Underwater thermal gliders have been around for a few years now. Hotel load is handled by a Lithium Ion battery with propulsion generated by a thermal engine that alters the vehicle's volume to adjust the buoyancy. These floats built by NASA (actually JPL and SIO) use a similar thermal engine to recharge their batteries. Since they only do vertical profiling with a minimal science payload and locomote by use of ocean currents, they are VERY low power. This is pretty much a rechargeable ARGOS float.

Re:Go "further", more passive? (1)

sznupi (719324) | more than 4 years ago | (#31800872)

How "direct" is the thermal engine in case of those underwater gliders that you mention? (and anyway, from what I've heard I was under impression that gliders generally store all required energy in batteries; why wouldn't they, if this new approach of thermal engine just showed up and seems is just in a buoy for now?)

I was wondering about very direct approach - using contraction and expansion of materials (specific for temperatures expected during particular mission) which don't follow "normal" thermal expansion, to directly affect buoyancy in desired way. Now that I think about it, even with buoyancy pump included anyway (to stay on the surface when required), it still might be worthwile considering the pump wouldn't have to work against nearly the same pressures?

Re:Go "further", more passive? (1)

psgalbraith (200580) | more than 4 years ago | (#31801282)

ARGO float, not ARGOS. Common mistake.

http://www.argo.net/

Re:Go "further", more passive? (1)

Viperpete (1261530) | more than 4 years ago | (#31807164)

The Deep Flight Merlin [deepflight.com] is positively buoyant and operates as an underwater plane.

Lagrangrian? (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#31799978)

Who put that second 'r' in there?

How hard can it be? (1)

BlackPignouf (1017012) | more than 4 years ago | (#31799980)

How hard can it be to not mess up units while talking about energy and power?

How far can a 80 mph car go?

Re:How hard can it be? (2, Funny)

fuego451 (958976) | more than 4 years ago | (#31800166)

"How far can a 80 mph car go?"

About 580,000 rods per hogshead, depending.

Re:How hard can it be? (1)

tsalmark (1265778) | more than 4 years ago | (#31800238)

For blog authors, very hard it would seem. The initial article states it in watt hours "1.7 watt-hours, or 6,100 joules, of energy per dive"

propulsion (0)

Anonymous Coward | more than 4 years ago | (#31799990)

A Lagrangrian Observer is most probably going with the flow and does not need propulsion power. It will follow the streams of water and report its measurements and position.

But can it steer? (1)

plover (150551) | more than 4 years ago | (#31799992)

Can this robot hold a position, or return to a position upon surfacing and learning its position? Or is at the mercies of the ocean currents as to where it ends up?

Re:But can it steer? (1, Informative)

Anonymous Coward | more than 4 years ago | (#31800118)

A steering AUV which is propelled under the ocean's thermal gradient is being developed by Teledyne Webb Research:
http://www.webbresearch.com/thermal.aspx

This has been around for a number of years so while the parent story is perhaps the first to be 'entirely' powered, the ocean has been powering such devices for years. The current model is 4th or 5th generation and is currently being flown in partnership with Rutgers University Institute of Marine and Coastal Sciences:
http://rucool.marine.rutgers.edu/
To track see the blog:
http://www.i-cool.org/?cat=75

For more information contact via the RUCOOL webpage or through Teledyne Webb Research's site.

Can it steer? No, it can't? (1)

Animats (122034) | more than 4 years ago | (#31800564)

Can this robot hold a position, or return to a position upon surfacing and learning its position? Or is at the mercies of the ocean currents as to where it ends up?

No, it can't. It can adjust its depth; that's all.

Compare the Wave Glider [liquidr.com] , from Liquid Robotics. This is a privately funded product. It has two parts, a surface "floater" that looks like a surfboard, and a tethered "glider", which hangs below it, about 10m underwater. Wave action on the floater pulls the glider up, and gravity brings it down. Spring-loaded ailerons move the glider forward, powered by the wave motion, and it tows the floater. A rudder on the glider allows steering. The floater has solar panels, a GPS, and an Iridium satellite data link.

The Wave Glider is not only autonomous and self-powered, but can make long trips under control [nytimes.com] . First they sent one all the way around the Big Island in Hawaii. Worked fine. Then they sent it from Hawaii to California. This took a while; it averages around 1 knot; more in storms, less in calm weather. In storms, the floater is pulled through waves, like a surfboard, and comes out unharmed. They picked it up in Monterey Bay, saw that it was in good condition, and sent it back out again. They parked it in Monterey Bay for a while, circling in a 50 meter circle. Then they sent it back out again on an trip to Alaska and back.

The Wave Glider generally stays within about 50m of its programmed course. The Coast Guard treats it as "floating debris", and it doesn't show lights. If something hits it, it's like running over a surfboard. The control center on shore (a laptop with an Iridium phone) gets ship tracking data, and they guide the Wave Gliders out of the way of large ships.

Re:Can it steer? No, it can't? (0)

Anonymous Coward | more than 4 years ago | (#31803100)

Can it go deeper than 10m?

Yes, it can!

Wave glider is pretty neat technology, but to imply that the waveglider is somehow better because it can steer is retarded. Both obviously have their advantages and disadvantages. The waveglider has solar panels that stay on the ocean surface and are tethered to the glider part, so its capacity to perform science at depth is very limited. With a thermal engine you're not limited to the surface, and in fact you NEED to go below the thermocline for it to work. Two very different things, both awesome in their own way, and certainly not in competition with one another.

GPS? (1, Interesting)

Anonymous Coward | more than 4 years ago | (#31800054)

Hm? Underwater GPS receiver? I am quite sure that the readio signals from the satellites do not pass through water....
Did I miss something?

Re:GPS? (0)

Anonymous Coward | more than 4 years ago | (#31800264)

To find it when it resurfaces, durrrrrrr.

Re:GPS? (0)

Anonymous Coward | more than 4 years ago | (#31800300)

Why, yes....yes you did miss something.

The AUV has a probe that rises above the surface of the water, allows the water to stream off the surface of the antenna package, and then it powers up, acquires a lock, and then uses another package on the same probe to hi the Irridium network with an SMS message with position and SPT measurements and health data from a COTS sensor.

All this is great- but far costlier and less functional than adding primary batteries that could last for years in the unit. However, this method does have obvious military applications that require longer operational life. This is the raison d'etre for Teledyne being interested at all.....

Re:GPS? (2, Funny)

Bearhouse (1034238) | more than 4 years ago | (#31800550)

Hm? Underwater GPS receiver? I am quite sure that the readio signals from the satellites do not pass through water....
Did I miss something?

The spell check?

Re:GPS? (1)

sugarmatic (232216) | more than 4 years ago | (#31803472)

The vehicle has a probe that sticks out over the surface upon surfacing. After a short wait to allow the hydrophobic antenna cover to shed water, the GPS antenna is used to get data, and the Iridium antenna is used to send a message via SMS to the network with the data from a COTS PTS sensor and the GPS data and other health data.

LavaLampDrive (0)

Anonymous Coward | more than 4 years ago | (#31800282)

Captain! They've hit our LavaLamp Drive !

Re:LavaLampDrive (1)

sugarmatic (232216) | more than 4 years ago | (#31803578)

succinct. but the system is a phase change system, not a liquid density system.

A new energy source? (1)

Pawnn (1708484) | more than 4 years ago | (#31800314)

I don't recall hearing about this technique for producing energy before. I wonder how useful it would be to make a similar device to produce energy and send it back up...

Re:A new energy source? (1)

Cheerio Boy (82178) | more than 4 years ago | (#31800512)

I don't recall hearing about this technique for producing energy before. I wonder how useful it would be to make a similar device to produce energy and send it back up...

I'm betting that if it isn't a simple stirling engine of some sort (maybe a miniature form of what's in the Kockums submarine [stirlingengines.org.uk] ) then it might be some form of OTEC [wikipedia.org] which would explain the "per dive" referenced in the article as it has to pass from one thermal extreme to the other.

Underwater robot powered by nature (1, Informative)

Anonymous Coward | more than 4 years ago | (#31800388)

We did run this story on April 07, 2010 (link is here: http://www.global-adventures.us/2010/04/07/underwater-robot/). Temperatures at depth are not always easy to predict since they are influenced by many factors including ocean currents, light penetration (i.e. algae bloom). If it's made available, this technology will allow scientists to cover larger bodies of water, gain more data and over time a better understanding of whats going on in our Oceans.

Atlantic Glider (1)

blcarmadillo (929312) | more than 4 years ago | (#31800470)

What about Rutgers glider, Atlantic Glider, that has already crossed the Atlantic ocean? If I'm not mistaken it is completely powered by the thermal difference between the surface of the ocean and deeper water as well. http://rucool.marine.rutgers.edu/atlantic/ [rutgers.edu]

Re:Atlantic Glider (1)

Superdarion (1286310) | more than 4 years ago | (#31800864)

And let us not forget the ancient technology which Columbus used to cross the atlantic! I heard it was powered by wind and oceanic currents!

Re:Atlantic Glider (0)

Anonymous Coward | more than 4 years ago | (#31801368)

Alkaline batteries.

Re:Atlantic Glider (1)

sugarmatic (232216) | more than 4 years ago | (#31803562)

The Rutgers vehicle depended on primary batteries, which is arguably the wiser choice for a variety of reasons. Primary batteries are used to successfully deploy ARGUS probes for years at a relatively low cost (I believe $5k a copy or less), and even power the displacement pumps used for profiling. The passive wax system is nothing new and can be more economical for longer missions than primary batteries for profiling control, although there is really no size or weight advantage. The use of the phase change system to power mission electronics seems very interesting, but I would argue that it is a solution or niche missions (read military and perhaps some energy industry apps here). The primary batteries are cheap, no larger, and likely cheaper to deploy in development and fabrication costs than the mechanical fluid energy extractor employed.

Teledyne is likely seeking military biz on this one. They were/are also in development of stealthy passive gliders that could move into position under water at station for years.

What about barnacles? (0)

Anonymous Coward | more than 4 years ago | (#31804654)

A robot that stays in water for an "indefinite amount of time" still has to worry about keeping the barnacles off. After a while, even 1.7 watts wouldn't be enough to get the robot anywhere. See this article: http://spectrum.ieee.org/robotics/industrial-robots/remotely-piloted-underwater-glider-crosses-the-atlantic

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