Slashdot Mirror
Skyhook Robot Passes 1000 Foot Mark
JhohannaVH writes "MSNBC.com is running a story about yesterday's successful test of the Space Elevator!! Maybe it will become a reality after all." From the article: "This week's testing involved a 12-foot (4-meter) diameter balloon. Safety lines held by team members kept the balloon from floating away. The ribbon dangling from the balloon was made of composite fiberglass, with the robot lifter running up and down the tether ... During the day, the highest altitude reached by the balloon/ribbon/robot combination was 1,000 feet (305 meters). 'It gives us complete confidence that the mile goal is well within reach,' Laine said. Laine said that the Federal Aviation Administration has been very supportive and helpful in orchestrating their test flights. "
A journey of a thousand miles begins with a single step.
If I could, I'd destroy you all.
A fifth of a mile may be a tiny fraction of the distance needed to climb a real space elevator, but that's almost beside the point. If this doohickey can climb 1000 feet it can climb a hundred million, assuming the battery holds out. It just has to keep trundling upward.
The cable is the scientifically hard part, not the climber.
This thing is of course, pretty cool, but it seems to me to be a pretty basic mechanical device. My understanding is that developing ultra-high tension/flexibility nanofibers capable of stretching from Earth to orbit, and developing the orbital platform was what made construction of a space elevator difficult.
My two cents.
_________
As Diddy says: Don't pull out your wallet if you ain't going to use it.
------ The best brain training is now totally free : )
Nice, only of course this 'test' misses the one crucial, difficult part; the material to make the wire from. The space elevator will be built (either in tether form or in straight up crawl-up-the-nanotube form)...as soon as we can create the lenght of the material needed. That is the only technology needed to be tested; the rest (ie what they tested here) is a relative no-brainer on which funds needn't really have been spent. Proof of that; I doubt they learned anything crucial (or even really relevant) which can be applied to the real, fuill scale thing.
-- Waht? Tehr's a preveiw buottn?
Please, someone convince me of the economic viability of a 23,000 mile train journey. Not the technical viability, assume it can be done.
Government of the people, by corporate executives, for corporate profits.
Yes, why not? In theory you just need to go a short distance past Geosynchronous orbit, which is about half that, but only if you have a very heavy counterweight.
By increasing the distance they reduce the counterweight mass.
http://michaelsmith.id.au
I believe what I said here still applies:
Makes some sense to me.
And me too
"What do you despise? By this are you truly known." --Princess Irulan, Manual of Muad'Dib
/)
Right. Geosynchronous orbit is around 30,000 miles up, and you need a cable twice as long to balance it out (60,000 miles up), at least in a number of common designs. What's so unusual about that, besides being as an impressive leap of imagination as any space elevator concept? We're talking about engineering on beyond a grand scale here.
Personally, I'm still impressed that they went ahead and tried out the 1000 foot model, and that it seems to have worked more or less as they expected.
It's a big jump from a fifth of a mile to tens of thousands, and the cable technology isn't there, but every journey starts with the first step.
Wake me up when they have build a carbon nanotube 1000 ft long of the required strength. That'll be something significant.
Making a little device to climb 1000 ft is not significant. It's like building a single rivet, and saying, "look, we're part way to a 777!" Technically, yeah, but you haven't done any of the hard bits, such as all the materials science that goes into the fanblades in the engine.
The hard part of the space elevator is NOT the climber, it's the bloody cable.
Of course it's a PR event. Guess what? Our lack of a space elevator is a PR failure. You seriously think that with one or two hundred billion $ (i.e .5 fewer oil wars) we couldn't overcome every lingering engineering hurdle and build one of these things? So many of today's problems are described as scientifically insurmountable when really, it's just a question of misplaced priorities. With a really large (but not infeasible) amount of money we could cure cancer and AIDS, blanket Africa with enough doctors and teachers to spark a humanitarian revolution, and have prolly enough left over to get fusion/microwave power off the ground. Take your pick. The American voters have, and that's why things are the way they are. Launching a public awareness campaign for whatever your pet cause is looks like a smart move to me.
I think there is a world market for maybe five personal web logs.
Enough with the dupes about the retarded space elevator. We get it and we don't care. Whoever keeps posting these stories must from Attention Deficit Dis... Ooh shiny penny!
"You'll get nothing, and you'll like it!"
The theory seems to be that you start small, and you get progressively bigger and bigger until all of the problems are solved. The first time it may have been a small motor with a battery climbing a 100 foot rope up the side of a building. This time it was an 18th generation lifter with cargo capacity climbing a 1,000 foot high tensile ribbon connected to a balloon. Next time it may be a climbing a 10,000 foot high tensile double ribbon using laser power. Or maybe it will be a 1,000 foot carbon nanotube wire in a year-long stress test, with a climber specifically designed to do maintenence on the tether.
Eventually they'll get there, and this is a definite step in the right direction. While the tether may be the biggest unknown of the project, we still don't have much experience with this sort of thing. What safety systems should be on the lifter? How should it be powered? How long will such a thing last before it breaks down? How long will the tether last? How will the system weather storms? How will it weather space debris? How will you find a patch of ground strong enough to anchor the thing to? How do you keep the climber from jumping the track? How do you keep parts from freezing as it goes from wet tropical climate into space? The theoretical engineering may be done except for the cord, but many, many practical engineering considerations remain.
I applaud this team's efforts, and wish them much luck.
The ______ Agenda
So instead of tethering the cable to a balloon and having it climb a measily thousand feet, why not loop the cable around a couple of pulleys to form a cable treadmill, and let the climber "climb" all the way? Give the climber a real workout. This test smacks more of publicity stunt than of useful research to me.
"I'm not impatient. I just hate waiting." - My Dad
But what might really do it in, though, is this ribbon is going to be a giant electrical generator. As it orbits through the earth's magnetic field, it's going to develop a tremendous charge along its length. What will dissipate that charge? Is the fiber going to be adequate to carry that charge? Do we ground the terminus or use the current? And what happens to the fibers as the ribbon expands, contracts and flexes throughout the day? Will microscopic voids appear in the fiber, which may in turn cause tiny arcs? And might these arcs eventually burn through the fibers, causing catastrophic failure?
Incorporating 22,000 miles of 0000 gauge copper welding cable is not likely to be a good answer, at least not from a weight / strength / cost perspective. But something will need to deal with the charge, and I've seen nothing so far that does.
So, throw in several dozen masters' theses worth of materials science, and you want it to magically incinerate as it falls, too? Well, why not?
John