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$2 Million NASA Power Beaming Challenge Heating Up
carstene writes "Qualification rounds for the NASA Centennial Challenge Power beaming contest are underway at the Dryden Flight Research Center. The contest uses a scale model of a space elevator as a race track. Entrants must build a robot to climb a cable, suspended by helicopter, 1 km into the sky without any on board energy storage. The teams are using high power laser beams to transmit power from ground stations to photovoltaic arrays on the robots. If a team can accomplish this at 5 meters per second average speed then they could win up to 2 million dollars. One day this technology could be used to power rovers in shadowed areas of the moon or to recharge electric UAV's in-flight or even a space elevator in the far future. A blog of the event can be found here. Full disclosure: I'm a member of the LaserMotive team that you can follow on twitter, or or via blog."
Last I heard there were bigger problems with space elevators than the energy required to get up there.
A circular geosynchronous orbit in the plane of the Earth's equator has a radius of approximately 42,164 km (from the center of the Earth). A satellite in such an orbit is at an altitude of approximately 35,786 km above mean sea level.
Would microwave + rectifier work any better or worse? Just wondering, I seriously don't know.
Isn't "full disclosure" really just meant to say "Hey, FYI I might be biased"? Not, "Hey, I might be biased, now let me promote myself!".
He was just demonstrating his bias for full disclosure.
To be serious though, he is providing relevent and interesting information. We wouldn't have much news if you can't tell anyone what you are doing for fear of seeming self-absorbed.
My webcomic
NASA: "We'd like you to hover for a few hours dangling a cable."
Pilot: "Boring!"
NASA: "Oh, and several teams will be shooting lasers in your direction."
Pilot: "Now you're talking!"
That "full disclosure" sure is a sneaky way to promote yourself in the article!
what brave soul wants to pilot the test helicopter anchoring the top of the beanstalk, while engineers of varying degrees of competence are aiming powerful directed energy beams at an object suspended a short distance below them.
"Do not glance outside of cockpit with remaining eye."
Welcome to the Panopticon. Used to be a prison, now it's your home.
I'm confident I can get much higher speeds than that out of a laser...
Village idiot in some extremely smart villages.
Kool idea but I would imagine that unless those solar panels could travel down the tether they would be rather expensive to repair and maintain. Being attached to the climber they could easily be maintained when it returns to Earth.
We could use a defense from an alien armada, or a death star-esqe laser that we could use on other planets.
Anything can be found funny, from a certain point of view.
How often do the solar panels get changed on current satellites?
If you have a cable already going from the ground to space, why beam the power down? Run a cable along side the existing cable to get the power down.
Then again, 45K of wire per strand is going to use a lot of copper or any other material.
I didn't see on the site though, what day is the competition itself? I'd like to go out and watch it. (I work in a building right down from DFRC, on main base)
Isn't "full disclosure" really just meant to say "Hey, FYI I might be biased"? Not, "Hey, I might be biased, now let me promote myself!".
No. In fact, your point is self contradictory. If it means the former, it necessarily includes the latter. It's not possible for the first thing you said it meant to be true while the second is false. Rather like it's impossible for a basket that contains five apples to not contain three apples. Just because you include more than the first thing doesn't mean you no longer include the first thing. If "full disclosure" means including a notice of how you might be biased, including that notice and saying something else as well does not mean you failed to include the notice, so it's still "full disclosure".
"Convictions are more dangerous enemies of truth than lies."
You can't run the power down a wire until you have true room temperature superconductors. Even they do not have unlimited current carrying capacity...
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Don't forget how much resistance 35,000 odd kilometers of copper wire would have, and its weight.
When our name is on the back of your car, we're behind you all the way!
Exactly, Knowing someone is biased doesn't give you any information into how he might be biased. It's important because instead of reading everything as a skeptic, you could now just be skeptical about his team rocking while the others suxors.
Here is a better example, A judge could potentially be biased because he has met the defendant before. Disclosing this isn't an automatic requirement for a recusal (judicial disqualification) because the disclosure could be that he saw the defendant at a charity dinner where he sat two tables away some 20 years ago. But if the disclosure would state he was a business partner and stood to lose a deal of money if the defendant lost, it would be. SO knowing the why or the how of the disclosure is just as important as the disclosure in most cases.
Isn't "full disclosure" really just meant to say "Hey, FYI I might be biased"? Not, "Hey, I might be biased, now let me promote myself!".
No. In fact, your point is self contradictory. If it means the former, it necessarily includes the latter. It's not possible for the first thing you said it meant to be true while the second is false. Rather like it's impossible for a basket that contains five apples to not contain three apples. Just because you include more than the first thing doesn't mean you no longer include the first thing. If "full disclosure" means including a notice of how you might be biased, including that notice and saying something else as well does not mean you failed to include the notice, so it's still "full disclosure".
First of all, holy crap could you make that any more confusing? And thanks for explaining to me that a basket with 5 apples can't not have 3 apples in it - when you think someone is that wrong, maybe you should consider the possibility that you misunderstood them? People are rarely that dim.
And it doesn't matter anyway, you completely missed my point. I never said what he did wasn't full disclosure, i was just suggesting that that the self promotion was unnecessary.
-Taylor
Worldwide Military budgets: $2100 billion. Worldwide Space Exploration budgets: $38 billion. Really, world? Really?
er, it IS private industry doing the research..... NASA is merely offering a prize that is frankly hellishly little money considering what they are asking.
If you mod me down, I will become more powerful than you can imagine....
Is there anything like a mechanical diode - like shark skin.. something that would ratchet the platform upwards in response to vibration in the cable?
What about blimps? Vacuum filled(oxymoron alert) carbon nanotube spheres? What about something like aerogel but with a closed-cell structure that lacks air?
http://www.masturbateforpeace.com/
Wouldn't a two piston Sterling Engline designed such that it flipped itself over on each cycle be a much better energy down converter than solar cells? Even if your laser is tuned to the solar cell band gap, the amount of energy that you put into the power transfer is a fraction of what you would get as useful energy to the crawler. With a Sterling Engine you could just use mirrors to focus sunlight to power the device.
I can see why they'd want to use lasers - how else are you going to focus the energy sufficiently from a distance of 1 or more kilometres?
But why would they use lasers and PV cells when masers could be used instead? Highly directional radio antennas should be both simpler to build and waaaaayyyy more efficient, IMHO, and masers aren't any less efficient than lasers...
I have no problem with your religion until you decide it's reason to deprive others of the truth.
Note that these current designs are, effectively, using solar cells. They're just using ones tuned to specific frequencies and powering them with lasers, rather than sunlight. Even then, it's difficult to get a good enough power to mass ratio.
I am TheRaven on Soylent News
Well c isn't even a letter, so it can't be that fast can it?
My first thought was that if TFS made some corny joke about microwaves from space killing cows on earth, a kitten was going to die. Lucky for us it's about lasers from space instead!
Step 1 - Find Blue Shark (Reliablely recorded at speed is 24.5 miles (39.4 kilometres or 11.1m/s) per hour over long period of time) .....
Step 2 - Attach laser
Step 3 - ???
Step 4 - Profit
No! Don't do that! The laser would be applying a pressure in the wrong direction. If you must, reflect it on a mirror on earth so the light can bounce back up to the craft. (In all actuality, the force from the light pressure is probably insignificant.)
Stylish sheet to fix many problems in Slashdot's D3: https://gist.github.com/801524
I'll supply the power over a single conductive cable 1 km long if you'll supply the robot to climb it. We can share the prize. I'm ready to demonstrate. To see how I do it see http://www.corridor.biz/FullArticle.pdf n6gn
The scariest thing about this is being on the ground, next to the cable, hooking up a climber with a big Sikorsky S-58 above you. Ever see what happens when a cable under 800lbs of tension snaps? Think Amusement park nightmare.
For this test, a big freakin' light source (at the solar cells peak absorption wavelength) and an array of lenses to focus the light on the robots solar cells should do the trick ...
Indeed, it's time that someone invents the carbon nanotube unlimited current room temperature superconductor, so that we can have cables carrying electricity from space without loss, and without collapsing under their own weight.
The Tao of math: The numbers you can count are not the real numbers.