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Carefully Timed Jerks Could Power Space Elevator
Hugh Pickens writes "BBC has an interesting article on the long-standing issue of how to power the 'climber' that would ascend a space elevator into space. Previous ideas have included delivering microwave or laser power to the climber beamed from the Earth's surface, but now European Space Agency ground station engineer Age-Raymond Riise has demonstrated a device that could provide a "lift into space" for cheaper space missions along a 100,000-km long tether anchored to the Earth. Riise demonstrated sending power mechanically by providing carefully timed jerks of the cable at its base with a broomstick to represent the cable held in tension, an electric sander to provide a rhythmic vibration to the bottom of the stick, and three brushes representing the climber with their bristles pointing downwards allowing the climber assembly to slide upward along the broomstick as it moved slightly downward, but grip it as it moved slightly upward. 'It would be possible to make a suspension system that completely decouples the cabin where the passengers are,' says Riise. 'For them it would be a linear movement with very little disturbance.' Riise says that he has been approached by commercial elevator companies, who are researching new ideas for elevators in superscrapers where the simplicity of the approach makes it attractive when compared to other ideas for powering lifts, such as compressed air."
...can be used to power the space kleenex dispenser.
EVER is a long time.
The Space Elevator is something an advanced civilization with a few hours to kill might whip up.
How we know is more important than what we know.
"Why is everyone so obsessed with this terrible idea? Even if we got it to work, there's no way we'd be able to afford the maintenance and energy costs. It just isn't viable."
This guy just copied and pasted his post. I found this same post about plane flight, the space shuttle, the hubble, the mars rover, and the lightbulb.
ok, i lied, but you get the point :)
There's nothing Intelligent about Intelligent Design.
Actually, this is something the average person can see at home. The idea he's describing is a ratcheting mechanism, and is an excellent idea easily seen to be of use in any amateur environment.
My only concern is what happens when those bristles get a little worn out after all that high intensity cyclic stress and an elevator load of passengers plummet to their doom from 100 km up. Gonna need a really good preventative maintenance regimen, not something commercial operations are typically known for in the industrial sector.
When you're afraid to download music illegally in your own home, then the terrorists have won!
Consider how much energy it would take to move this massively long cable. There is no way in hell that is going to be efficient. You're going to be wasting a massive amount of energy as you move the entire cable the whole time the thing is climbing.
To the naive this approach seems workable because it looks simple. The fact is that it takes a certain amount of energy to do things and this is probably a very poor method that will become quite obvious at the scale we are talking about. In this house we obey the laws of thermodynamics and all that...
Then you have to consider the wear and tear on the mechanical parts, especially that really expensive long cable into space. This just seems like a bad idea all around.
The ratio of people to cake is too big
It's one thing to vibrate a broomstick in that manner, and quite another to do so with a 36,000 km space elevator. No matter what material you're using, you're looking at a very large mass; wikipedia estimates "a minimal, very low payload space elevator 'seed ribbon' could have a mass of at least 18,000 kg." -- or just shy of 20 tons. For hauling passengers and goods, you'll need much more. Now, we're talking about accelerating and decelerating this mass of at least 20 tons multiple times per second.
Think about that. We're talking bringing something the weight of a big-rig, accelerating it to a decent speed, and then bringing it back to a stop in a fraction of a second. That requires incredible force. Now, think about the time it takes to accelerate a big rig to highway speeds, and then bring it to a full stop. Now, remember, that's the *minimum* mass we're dealing with. A full-scale elevator is likely to be quite a bit heavier. For another point of reference, the 250 ton commuter train I ride to work every day, if it applies full breaking force in an emergency situation, takes roughly 2,500 feet to come to a complete stop.
And not only do you have to do that, you have to not shake the thing apart in the process. And on top of that, you have to do that without exerting too much force on your passengers; humans can't handle much more than a few Gs.
The other glaring hole is the brush bristles. It's one thing for a coarse brush to support a few ounces of wood, and quite another for it to support a multi-ton cargo container while undergoing rapid acceleration multiple times per second.
Has anyone done the math necessary to show that this idea can actually scale? Because at first blush, it sounds ridiculous.
I was talking about us.. in a few thousand years.. hopefully after all the dickwads who think making the earth a utopia is achievable have buggered off.
How we know is more important than what we know.
It might not be Flamebait but theres no mod option for 'Pathetic unfunny shit'.