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New Wave of Fusion and Robot Innovation at MIT
An anonymous reader writes "Popular Mechanics has been getting some great access inside the labs at MIT all week, and they've gotten some interesting looks at developing technologies. Robot-assisted rehab with gaming-style controllers comes out of the biomechanics lab, blind and crash-proof UAV testing with F/X cameras is being done at the aerospace controls lab, and work on electric scooters with super-cheap assembly is proceeding at the Media Lab. Perhaps most exciting is a fight for funding while the holy grail of clean fusion power in reach at the plasma center. The article on fusion predicts, "We'd see economically feasible fusion power by 2035, at the earliest, and increasingly efficient commercial reactors somewhere in the middle of the century."
Will this mean that Karl Stefanovic will now gain some siblings?
and what have YOU done about it huh?
How we know is more important than what we know.
Tokamaks will never be cheap, nor efficient.
Inertial gravitational containment is the holy grail.
Inertial electrostatic containment is the next best thing.
How we know is more important than what we know.
Yes! Clean, reliable fusion power is only twenty years away...remarkably, this has been the case for over 40 years.
"And then, there's the inevitable bad news: The first-gen RoboScooter will not be very robotic. The original concept developed by the Media Lab's Smart Cities research group called for wheels that were essentially self-contained robots, with dedicated processors that could optimize braking and suspension. In a four-wheel configuration, these wheeled bots would also control steering. The group's City Car design, for example, allows each wheel to turn independently. For a scooter, computer-controlled steering isn't necessarily more efficient than old-fashioned handlebars. But for now, the point is moot, because the first RoboScooters to hit the streets won't have wheels any more intelligent than a Vespa's."
Does the 2035 RoboScooter sound a bit too much like a SegWay?
I see that flying car or something else that's been on Popular Science's front page in real life. Glad I canceled that stupid magazine subscription thirty some odd years ago. BTW, anybody know if Scientific American has been following Popular Science into the crapper too ?
The truth is, we still don't fully understand how plasmas act in the real world. The article alludes to this, by mentioning turbulence and instability. Fluid models and magnetohydrodynamics just aren't detailed enough, and full-blown simulations are far too complex to be of much use on a fusion-reactor scale.
A key concept is "transport". What a fusion reactor requires is to keep heat bottled up. The ions in particular need to be kept hot so that they can fuse. What happens, though, is that heat gets dumped from the ions into the electrons (which are useless for fusion) at a rate which exceeds theoretical predictions -- one of many "anomalous transport" phenomena. (Great phrase, which you may recognize from HL.)
Bottom line: we need to do more research on fundamental plasma physics for fusion. Yet for whatever reason, fusion funding has been dropping for decades.
Link directly to the cities.media.mit.edu info/scoot photo...
/.Soulskill/anonymous(again /.)/PM biz ...enjoy.
Bypassing the ever-silly:
-=-=-= -=-=-=
Scooter with ITRI and Sanyang Motors
RoboScooter - Clean, Green Mobility for Today's Crowded Cities
The RoboScooter is a lightweight, folding, electric motor scooter. It is designed to provide convenient, inexpensive mobility in urban areas while radically reducing the negative effects of extensive vehicle use - road congestion, excessive consumption of space for parking, traffic noise, air pollution, carbon emissions that exacerbate global warming, and energy use. It is clean, green, silent, and compact.
People Ryan Chin, PhD Candidate, Smart Cities, Media Lab Yaniv Fain, Sloan School Michael Chia-Liang Lin, MSc Candidate, Smart Cities, Media Lab Arthur Petron, Mechanical Engineering Raul-David "Retro" Poblano, MSc Candidate, Smart Cities, Media Lab Andres Sevtsuk, PhD Candidate, Dept. of Urban Studies & Planning
SYM/Sanyang Motors Grand Wu Wan Ching Chang
ITRI Wen-Jean Hsueh Eugene Hsiao Ying-Tzu Lin Barbara Yeh
I don't know about anyone else, but I asked some nuclear physicists very nicely and they assured me that they would build me one...
... to power the mecha that I asked some robotics and mechatronics guys to build me.
A game has objectives and is competitive, anything else is just play
Aren't we already in "The Future" right now? We should already have fusion power and cool robots doing stuff for us! What happened?
http://www.nap.edu/openbook.php?record_id=9986&page=87
That's a great question!
I worked for two years at General Atomics trying to model and understand the interaction of fusion plasmas with the reactor walls. I've seen people here who have done more.
Like many other people who have worked/are working on fusion, I don't think it's going to be commercially viable this century. The problem is materials. It's simply too expensive to build these things.
Which leads to a resonance cascade scenario, ands ends with you rescuing the scientist's beautiful daughter.
how do you create tags? I'd love to see something like 'MITlove'
http://en.wikipedia.org/wiki/Jury_nullification
" Even that protracted timeline now appears optimistic. Since 2006, when seven member countries committed to the ITER's $10 billion budget, federal funding for scientific research in the United States appears to have bottomed out. The U.S. agreed to pay 9.1 percent of the project's total cost--but of the $160 million contribution planned for this year, Congress has approved just $10.7 million. Porkolab says eight ITER engineers had been laid off without severance pay. "
I love how we can spend a shit ton of money on a ridiculous fantasy war and we wont actually fund something that actually has some merit. Too bad the terrorists missed and got the wrong people, they should of went after our congress. What a bunch of worthless old people that run our country.
These articles are about the only things that restores my faith about humanity. That is sad.
Cheap fusion is just around the corner--20 years from now. It's been that way for 30 years, and it will continue to be that way for the next 50 years.
cool then i can have my flying car and house on the moon.
If you mod me down, I will become more powerful than you can imagine....
You should look China when you are talking about Scooter.
They have a wide selections in Carrefour, or whatever Supermarket.
Price tag: ~1200RMB (150USD). Probably can goes up to 30MPH.
May be not as stylish as the MIT one, but definitely cheap, usable and actually are all over the streets. And there are more scooter than bicycle on the street.
Some models looks just like more than a hack of Bicycle + Motor + Battery pack, but works! Most design with battery pack can be swap out, and can be plugged to the main directly for charging. I have seen the janitor in Office bringing her pack upstair for charging.
It's just cheap!
While I have no doubt that Dr. Bussard's heart (and science) is in the right place, he wasn't a terribly good frontman for this project in that lecture. He came awfully close to blaming his own failure on a cabal of conspiring fellow scientists--just about the clearest sign of pseudoscience, by anyone's standards.
If you're looking for investors in a room of savvy geeks without a physics background, there's few things you should try harder to avoid than to be mistaken for a quack.
A nagging question about these fusion devices they've been talking about: How do they plan on extracting the energy from the reaction?
By convection/conduction with waste products being ejected from the "reactor" (not a bad term, imho)? By radiation?
Are they intended to be connected to some thermodynamic cycle or something more exotic? What kind of heat transfer temperatures are people talking about? Several thousand kelvins, or something more conventional?
Studying material science in the context of fission feels a little bit like powering my car on Fabrigé eggs and bald eagle heads, when you consider the costs of most of the materials in the core. Of course, we all know that fission is wildly economical despite that.
My question is, how insane does it get with fusion material sciences?
Long before this century is out, I think we'll arrive at the point where we can no longer afford not to build these things (or fission plants as an alternative). So get back in that lab and get back at it!
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
To make hydrogen practical requires a carrier. There has been some experimentation with metal carriers, but by far the most efficient hydrogen carrier, packing in far more hydrogen per unit volume than even liquid H2, is carbon. Amazingly, someone/something long ago put huge deposits of carbon-encapsulated hydrogen in giant underground reservoirs for us to use.
The only problem is, the carbon carrier is *supposed* to be recycled, and we haven't bothered doing that, and instead have just dumped all the hydrogen stripped carbon into the atmosphere as CO2, in quantities large enough to alter the atmospheric CO2 levels to a worrisome extent. As soon as we start recycling the carbon like we're supposed to, hydrogen cars will take off. In fact, the infrastructure is already built!
True, but the 'often' in this sentence refers to a select sample, which is the sample of economically viable enterprises. If tokomak fusion is economically viable, it is likely to become more cost-efficient over time. However, if the concept is borderline, it could easily get more expensive over time, as has happened for fission reactors. The physics and engineering of fission are well-understood but costs are not coming down for a wide range of reasons. Plasma fusion on the other hand, requires some difficult physics problems to be solved before we even can build a pilot plant to begin to mature the engineering.
A massive problem for fission reactors is decommissioning costs - what to do with a million tonnes of radioactive reactor? The point that fusion protagonists often overlook is that fusion reactors will face a similar problem decommissioning. In both cases fast neutrons create all sorts of difficult and radioactive materials in and around the core that will be hugely difficult to dispose of. If it were my money, I'd invest in solving the problems with decommissioning and disposal of by-products from fission. But that would not be nearly as cool and sexy as trying to find a brand new way to make the same mistakes.
In theory, there's no difference between theory and practice; in practice there is.
Hydrogen already makes sense today. Not from a yield point of view, because as you showed efficiency may not be optimal yet.
But because it concentrates the problem difficulty (creating hydrogen in a carbon neutral way) into one single point (the hydrogen plant) and makes the whole distribution network independent of the solution adopted upstream to produce the fuel.
You will end up in the same situation as the electrical power grid, where the grid itself and the end-user appliance don't need to change or adapt to newer technologies producing electricity. Whereas using coal-burning plants (the ecological equivalent of your description current efficiency in hydrogen production) or nuclear plants, dams, wind, sunlight, etc... : Nothing needs to be adapted, you can always plug the plant to the grid.
In the same way, once there's a distribution network, all that needs to be changed is more efficient methods to produce the hydrogen. The network is already here.
Currently the problems is that if you want to replace current petrol-based car engines with something more ecologically friendly, you have to replace :
- all car engines with the new technology
- create an entirely new distribution network for the new fuel.
All this with the chicken/egg problem, of users not wanting the new technology because there's no useful and practical infrastructure to use it, and industries not want to deploy a new infrastructure because there aren't enough users in the market.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Create a localized intense gravity field using a Heim drive = really easy confinement!
Tsukasa: All I really want, is to be left alone...
If I'm still around, I hope it's India and not China coming up next. One thing I'll say for Britain, their colonies, however peaceful or violent their bids for independence, have retained a great deal of freedom for individuals.
ITER will burn for half an hour or so. Peak power output that the walls have to withstand is 10MW per square meter. That is peak power, not constant. ELM's are the problem. These are violent instabilities that dumps huge amounts of energy and particles onto the wall. Controlling these bastards is essential. If their severity can be reduced (kept under 10MW/m2), even if you get more of them, it's probable going to be okay. To illustrate the 10MW per square meter: only the Arianne V rocket has a larger output, and only for a few seconds at liftoff.
The second thing is that the combination of materials in ITER have never been tried before. Beryllium for the first wall, Tungsten for the large part of the divertor, carbon for the strike points in the divertor. No one knows what will happen if you put them all together in one large reactor.
Of the wall facing materials the carbon will get the blunt of the energy dissipated to the wall. So the carbon will get eroded. Carbon has a lower z value (less protons, thus less electrons to strip off, thus less of energy loss) than tungsten. BUT, carbon will deposit on the walls, incorporating the tritium. This is a problem!. First of all, tritium is radioactive. Safety regulations only allow a limited inventory. Once reached, ITER has to close down for maintenance. No one knows yet when this level will be reached. After a few weeks of a few days? One is acceptable, the other is problematic to say the least. And second, tritium (T) is hard to come by. Commercial fusion reactors, as will iter, will have to breed their own supply (n from the fusion + lithium in the wall will give you tritium). In this sense T is behaving like a catalyst to convert deuterium (D) into helium. If you use one tritium to generate one neutron that will only a problem, because you can't lose anything. And even if you get a bit more out of it, 1.2 T per n, you still can't lose to much of it. Thus you need to clean the reactor walls and reclaim the tritium.
Some time ago, I discovered a useful BS detector kit on the Skeptics' Forum, and Lerner failed a bunch of these tests, especially test 7 ("Is the development always "on the verge" of being ready? Is the "establishment" always "wrong", and the principal always right?") and test 8 ("Show me peer-reviewed papers and presentations at mainstream scientific conferences by the principals" -- Lerner hasn't published in any of the relevant fusion journals, and most of his peer-reviewed papers are very old and in cosmology journals far afield from fusion).
Dog is my co-pilot.
The last time I saw a friend of my fathers (who is part of ODU's experimental nuclear physics group), I asked him about the viability of fusion power. He said something to the effect of "Fusion power is the technology of the future -- and always will be." When I asked him why he said this, he repiled with something to the effect of "When I was in school in the 70's it was 50 years off, and now its 50 years off."
By the way, that same professor has a book coming out this April on estimation........
The walls of the reactor will heat up due to neutron collisions and radiative heat transfer. In ITER, this heat will be conducted to a water cooling system. Temperatures in the plasma will be millions of degrees. Temperatures at the first structural layer, the "blanket" will be somewhere around 1000 K, I believe. Definitely below the melting temperature of reasonable materials. The gigantic electromagnets keep the superhot plasma stable and away from the walls, as much to keep the plasma hot as to keep the walls "cold."
ITER, however, will not operate as a power plant. The cooling water will just dump heat through cooling towers. It's purely a research reactor to study the stability and sustainability of plasma's with Q > 1, and establish operational conditions for the next reactor, known as DEMO. Because it's not really intended to run for more than about 500 seconds at a shot, it's not economical to try to get useful amounts of electricity out of ITER, although adding a turbine in loop with the cooling system is not fundamentally out of the question.
DEMO will be designed for continuous or near-continuous operation. Depending how successful ITER is (and the International Fusion Materials Irradiation Facility, which will develop the appropriate materials for the high neutron flux in a fusion reactor), DEMO may be another intermediate research reactor to finalize a workable commercial design, or it may be the final prototype, with other commercial reactors starting construction about the same time. The plan is to use a similar cooling system, but connect a steam turbine to it.
Regarding the operational byproducts (primarily stable helium), there is a feature in the bottom of the reactor called a diverter. I'm not sure exactly how it works, but my understanding is the helium reaction product being heavier, it tends to the bottom of the plasma, where being on the periphery it cools more and falls out the vents or is magnetically guided out. Moving away from your question, the article says the first commercial reactors will be built in the 2035 time frame. Oddly the ITER team doesn't think so. My understanding is 2035 is potentially feasible if they are able to build DEMO as an operational prototype rather than an additional research plant, but if they need to do further research with DEMO, it will be at least 10, probably more like 15 more years before commercial plants will be available.
Of course, all of this assumes the member countries follow through on their financial and in-kind committments in a timely manner. The US butchered our budget for ITER contributions for 2008. Not a good move on our part, IMO.
As a final note, the article makes a big deal about MIT's PSFC. This strikes me as slightly odd. I'm sure the work being done at MIT is valuable for understanding plasma stability, but in my opinion the Japanese JT-60 reactor, which holds the endurance record for a sustaining a 28 second plasma burn and achieving conditions which with a different fuel mix would have exceeded unity, or the Joint European Torus, which is currently the largest Tokamak in operation (and fuels the reaction by shooting frozen pellets of deuterium into the core 50 times per second...how cool is that?) are both much more exciting.
Another response to my post (the one by Councilor Hart) gives a really good summary of the problems. You've got to clean/replace the reactor walls periodically if you want it to keep working (assuming you don't consume the walls). You also have huge superconducting magnets to buy.
It adds up to ~$1 billion to buy and you still have significant operating costs.