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No One Wins NASA Space Elevator Contest
volts writes "According to New Scientist no one was able to grab the two $50,000 top prizes in the recent NASA 'Beam Power Challenge'. The biggest limiting factor seemed to be that no team was able to meet the speed requirement, although a group from the University of Saskatchewan in Canada set the height record at 12 meters. Not quite geosynchronous..."
The biggest limiting factor seemed to be that NASA didn't offer enough money to get any remotely reasonable solution to the problem. Fifty thousand dollars is chump change to the kind of money needed to develop any of this technology.
Why too fast?
That's why its a challenge. If the parameters are too easy you don't get great innovation.
If I could change anything I would have allowed the competitors to design, build and provide their own energy source instead of using the NASA provided light. That would have allowed another track of innovation.
B O R I N G
I'm reminded of DARPA Grand Challenge 1. This, though, seems quite a bit easier than autonomous vehicles- perhaps not the tether, but the climbers seem straighforeward. Are solar panels really that heavy? Are they that inefficient? The article says there was only a six-month time period between the contest announcement and the contest, but there isn't much in the way of new technology needed here. What gives?
I used to carry a bottle of whiskey for snake bite. And two snakes. -Nefarious Wheel
I think it has more of a chance of working than you. How's the view from the family basement, junior? The thing that people fail to realize is that even if a project never reaches its goal, it has the potential to spawn innovation that can be applied to other problems. There is a quite a list of things that are NASA castoffs that are used in everyday life.
You are in a maze of little twisting passages, all different.
"Quick guys, we gotta find a way to spin the Earth up really fast so we can call our elevator geosyncronous. There's $50,000 at stake, people!"
--- Journals are boring; Go to my web page instead
They should set a slightly lower speed limit. This would encourage more people to work on the problem.
The minimum speed was 1 meter/s = 3.6km/h = 2.2369 miles/h. I can walk faster than that.
Geosynch is 35,786 km above sealeve according to wiki. At 3.6 km/h it would take over a year to get up to geosynch. They really should increase the minimum speed.
Fly me to the moon Let me sing among those stars Let me see what spring is like On jupiter and mars
Not quite geosynchronous...
Oh, it's quite geosynchronous (i.e. above the same point on the Earth surface). It's just not in orbit.
So close and yet so far from the world's perfect ID number
Maybe if we stacked them...
Go back to steam engines, stirling engines? If your power source is light, why bother with electrical engines? Use some liquid gas as fuel in a tank, use the projected light as a heat source, let the gas heat up in a combustion chamber (a piston?) and drive the whole thing up as a locomotive :)
You can't handle the truth.
Wonderful idea! Now all we have to do is build a skyscraper that's 22,240 miles tall, and we can use these babies to get into orbit.
Power source this time was limited to a single high-power searchlight... faster requires a whole lot more power, and it simply wasn't going to be available in time.
Most teams didn't have the chance to test at their own facility with their own searchlight, nor at the competition site. If you can't really test, you shouldn't assume highly efficient operations...
The tether in use wasn't that tall, and accellerating and decellerating a whole lot within the available vertical distance was a nonstarter.
This was a introduction to parts of the problem set, not a realistic attempt to engineer production grade tether climbers. Everyone involved knows that...
Excellent point! In fact, most Space Elevator proponents seem to miss the fact that the energy for the elevator isn't free. You still have to expend at least the minimum amount of energy required to move an object into LEO. The physics of the situation say there are no shortcuts.
What you DO gain is:
a) Slower ascent
b) Only minor (if not inconseqential) losses from air friction
c) Ability to expend the power over a long period of time vs. in a huge controlled explosion
d) A workable descent mode that doesn't require that the hull handle extremes
I'm all for the space elevator idea. However, a lot of people need to understand that this is NOT existing technology. While it's very much possible for the necessary breakthroughs to be completed in the next few decades, dropping everything and working on a Space Elevator would only mean that we'd lose space access for a very long time. That is why NASA is pursuing the CEV and not the Space Elevator as the next major launch vehicle.
Javascript + Nintendo DSi = DSiCade
Didn't they do this on Junkyard Wars with a jet ski engine, duct tape, and a couple pieces of PCV?
When will Windows be ready for the desktop?
It seems the solution to this problem is to add a basement.
That's what I thought. I was wrong.
The argument is reduced to spending for the sake of NASA jobs. Communism.
I suggest you read Slashdot
e) 'Unlimited' energy that can be created on location or fed from an existing grid, instead of shipping around limited quantities of hazardous chemicals. You'll need to choose between cheap and fast, though.
j.
You've missed a major point to the space elevator scenario--controlled descent.
In a standard descent, all the excess kinetic energy is wasted as heat. In a space-elevator scenario, you can use the energy of the descending cars to assist in powering the ascending cars. Net overall energy expenditure required is just enough to start the system and overcome the inevitable inefficiencies. Your average energy-per-car can be much lower than the rocket scenario.
... was disqualified for "inappropriate" elevator music... Under testing situations, all of our patients (read: monkeys, elderly, humans, and fish) were driven insane, then promptly driven sane, then insane, then sane, and so forth during the 62.5 mile elevator ride finished. After the tenth go around we decided the cost to hosing out the compartment filled with bile, blood, and bits of hair were not worth the cash prize. So it goes. Additionally, the PSP battery life wasn't sufficient to stave off elevator-maddness either. http://trs.nis.nasa.gov/archive/00000377/01/tm1085 37.pdf
The minimum speed was 1 meter/s = 3.6km/h = 2.2369 miles/h. I can walk faster than that
Not straight up, you can't.
Geosynch is 35,786 km above sealeve according to wiki. At 3.6 km/h it would take over a year to get up to geosynch
True, but as gravity decreases, you accelerate faster per unit energy. I can't be arsed to actually do any math, but 1m/s at 1G is going to translate into significantly higher velocity the further out you go. Besides which, if you want to use the elevator primarily for moving materiel rather than personnel, a one-year turnaround might not be too bad; throughput is potentially more important than lag.
Even for personnel, that's on the order of time it took to sail from Europe to America via wind power, and people did that.
Reality has a conservative bias: it conserves mass, energy, momentum...
I always thought having the energy stored on the ground was a good idea, and just giving the rocket an initial kick to avoid the first stage.
I remember reading about the amount of energy used to get a large rocket moving from 0 to x mph. If the first stage could be provided on the ground in the form of a gun or a mag-lev push, it would shave tons off the system and be reusable. Problem is, the cargo may have to take a lot of G forces, so it may only be good for dead weight cargo.
Just like spaceship one used a mothership to get things rolling, these systems could give the initial push without burdeneng the rocket with the requisite energy storage requirements.
Heinlein's Moon is a Harsh Mistress went into this a good bit, interesting idea.
Short of a superconductor, practical wired power transmission is measured in hundreds or at best thousands of miles. Tens of thousands would be too much to hope for.
Why would I try to win this year when the prize money doubles for next year? "Next year, both contests will be repeated but the top prizes will rise to $100,000." Let me guess... the year after that the prize money goes to $250k? Sounds backward to me...
I'm not clever enough for a sig...
Totally unnecessary. If the capsule goes up at 1m/s, it will run 1km in 1000 seconds and 200km in 200,000 seconds, which is about 55.5 hours. At that distance the speed of the capsule can be raised by other means.
You can't handle the truth.
Great minds think alike; fools seldom differ.
The top prize is 50K...deduct 50% for university overhead, about 12K for graduate student salary, 5K for professor salary, and you might have 8K for materials budget. What happens when you need a special diode that costs 2K?
It sounds like a great idea, they should sweeten the pot a little more (and I did RTFA, 100K won't be enough either).
"Who are you?" "No one of consequence." "I must know." "Get used to disappointment."
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Jules Verne thought that in the future man would get to the moon by being fired there in a bullet shaped craft from a gigantic canon, and for a time afterwards many scientists agreed that the easiest way to get something into orbit would be some form of "Verne canon". Of course then you get all those wacky guys in the 20s playing around with rockets with good results. Later some Germans sped up the research into these rockets to be used as weapons of war and the development of rocket systems well, skyrocketed. Several of their best rocket scientists went to the West after WWII and development continued, though this time the focus was split between missile design and space exploration. Meanwhile, in Canada a few nutty guys were involed in a little project called the High Altitude Research Program (HARP), the idea was that payloads could simply be fired into orbit by a huge canon, mind you the payloads would be inorganic (satellites, radar chaff, other innert material, etc) because the escape velocity would be too great for living creatures to widthstand.
At the time (the 60s) people were interested in sending people into space, not to mention the Canadian Gov't no longer had interest in the project it was killed off by 1967. Now, I think the focus has changed a bit (what with successful robotic expeditions and the desire for a cheap way to get material into orbit) that the Verne Canon might once again be relevant.
crazy dynamite monkey
\i{I have seen suggestions that ~46,000 mph or 13 miles/sec would get you into orbit.}
Orbital velocity for LEO is about 18000 mph, or roughly 5 miles/sec.
Earth Escape Velocity is about 25000mph, or roughly 7 miles/sec.
46000mph is so far beyond what is needed for orbit, it's ridiculous.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
Current estimates suggest that a space elevator will be deployed in 2045 or so. I lunar elevator could be done much sooner-and would have immediate practical value.
12 meters. That would be easy to launch a satellite into geosyncronous orbit. Just make it's orbital velocity 20,000 miles per hour.
I've hit Karma 50 and gotten a Score:5, Troll... I win!
And yet Edwards, who designed probably the most calculated-out elevator, doesn't call for this.
Why? Elevators would have to pass each other. You'd have to have multiple running at a single time, transferring energy. You can't transfer over the length of the cable, so they could only transfer when close - which means a *lot* of cars going up and down. Plus, at least early-on, up traffic is much more in demand of the cable's stress than.
I actually disagree with him somewhat on this one (largely because regenerating the energy is so very important, not just from an operational-cost perspective given low beaming efficiency, but from a thermal standpoint as well), the cars will be quite expensive just to waste or scavenge for parts in orbit, cargo/passenger return to Earth via rockets is incredibly difficult, and the extra stress put on the elevator isn't too much if you time things right), but the points made are quite valid ones.
I personally would support partial energy recapture, with ultracapacitors or high density batteries storing the energy for discharge in small widened "passing zones" that have embedded conductor cables. You time the launches so that the most stressed section (the connection to earth, which needs to be tiny and where any increase in bearing load propagates strongly along the rest of the cable) only ever has one car on it at a time. The less stressed portions of the cable can bear multiple cars much better.
He's just being nice so my real father won't freeze him in carbonite and sell him for spice.
Actually, that's not true. with a space elevator, the overwhelming majority of the energy is wasted as loss. High coherency lasers with acceptable atmospheric frequencies have less than 1% wallplug to energy output efficiency; microwaves are far worse. Then there's the atmospheric losses, losses in the adaptive optics, and losses on the solar cells (not as bad as one might expect since the cells are optimized for a single frequency, but still not great).
:) So, in the case of a space elevator, *assuming* that climber production/reuse costs are cheap, the operation is mostly energy constrained. Energy being proportionally cheap...
The benefit in the case of the space elevator is that the cost in rocketry doesn't lie in fuel - it likes in production and maintenance. There's a common rule in rocketry that if your fuel costs are a major part of your operational costs, you're probably doing something right.
He's just being nice so my real father won't freeze him in carbonite and sell him for spice.
I am quite annoyed that NASA would even risk $50,000 of mine and other tax payer's money on such a preposterous game.
But this is what government is for. In a republic such as ours, the presumption is that a service or commodity for which any dolt can see the need is going to be supplied by the private market. Why not? You can get rich doing so (cf. Gates, Bill). On the other hand, there are a few things that people as individuals or even large firms can't provide (such as national security) or won't provide because it isn't obvious they're going to work -- such as space elevators.
Enter the government. It's government's job to finance "preposterous flights of fancy," because private industry (very sensibly) won't. Most of that blue-sky stuff turns out to be nonsense, naturally, But some of it doesn't. Some of it, in fact, turns out to be ideas so ingenious that they seemed like pure folly to ordinary folks -- that would be you and me and nearly all other voters -- when they were originally proposed. And, of course, these are the clever ideas that will sustain our ability, a hundred years from now, to compete internationally on the basis of being smarter than anyone else, not working for less. I don't know about you, but I prefer to work in a high-wage, low-volume economy than a low-wage, high-volume economy.
Now, there's no doubt a proper amount of bread that government should cast on the waters. We could argue about that. But not in this case. I don't see how anyone who accepts the role of government in financing very basic research could figure that $50,000 out of a $1.8 trillion Federal Budget is wildly over the top.
Actually, I think we may be over-complicating it. Trains run on rails and pick their power up from another rail. If you can streach one cable to g-sync orbit, you can streach several. If the cable and orbital-station can 'stay-up' when stuff gors up or down the cable, why not have permenant stations?
Until some effective "power-beam", or practically-sized self-contained power source (maybe fusion one day) is developed, you can power capsules using good-old power-rail systems, with repeater generation stations along the length of the cable (or other adjacent cables) to off-ser power losses due to the resitance of the "power line".
And, if I am grokking this correctly, this line would be the temperature of geo-stationary orbit, or at least damn cold, and therefore super-conductors would be effective in slashing the need for repeater statations.
I wonder if there would be a pd between the top of the cable and the bottom? Free power, cool...
Arther C. CLarke wrote the definative "hard" sci-fi book on the subject, "The Fountains of Paradise" I think it was called...
why oh why did everyone try to build an ascending elevator? They could easily meet the speed requirements with descending types ;)
Even for personnel, that's on the order of time it took to sail from Europe to America via wind power, and people did that
http://www.bartleby.com/65/co/ColumbusC.html
On Aug. 3, 1492, Columbus sailed from Palos, Spain, with three small ships, the Santa María, commanded by Columbus himself, the Pinta under Martín Pinzón, and the Niña under Vicente Yáñez Pinzón. After halting at the Canary Islands, he sailed due west from Sept. 6 until Oct. 7, when he changed his course to the southwest. On Oct. 10 a small mutiny was quelled, and on Oct. 12 he landed on a small island (Watling Island; see San Salvador) in the Bahamas.
I get 2 months and a bit over a week from that, not over 1 year.
Fly me to the moon Let me sing among those stars Let me see what spring is like On jupiter and mars
Kind of puts a different meaning to the phrase...
Mmm, but let us think this all the way through. If there is no more international competition, then there is no more difference between nations. That means we all live under one political system.
/. denizens. And perhaps even very different from what a Wyoming rancher or Bill Gates or Robert Mugabe likes. Which brings up an interesting question: which political system is the one political system under which we're all going to live? Is it going to be my preferred system? Or yours? Or Gates'? Or (shudder) Robert Mugabe's?
However....my absolute preferred top-notch hurray huzzah political system is, I dare say, not quite the same as yours. Or as other
See, the nice thing about having lots of different countries with lots of different political systems, is that you have the chance, at least, of finding one you like and moving there to live under it.
Furthermore, if people can generally move around, it sets up a handy competition between political systems. Systems that oppress their people or which generally fail to help their citizens prosper lose population (note Soviet Russia and Communist China had a healthy emigration rate, and people will risk their lives to escape North Korea). Successful systems gain people, especially clever people who are more likely to be able to emigrate.
So, I dunno, I kind of like the fact that there's lots of political system in the world, just like I like the fact that there are lots of car companies competing for my allegiance. I just wish it was as easy for people to switch national allegiance as it is to switch which brand of car you drive. Then we might see some rapid reform among the nastier systems of government. Nothing like the prospect of being Top Leader of Nobody at All to make a dictator start rethinking his methods.
P.S. Instead of religion and nationalism as the top two leading causes of death in the world, can I nominate (1) bad hygiene and (2) stupidity? Seems to me the Black Death did in a lot more people in the late Middle Ages than the roughly contemporary wars of religion, and even in our own day far more young men died of drinking and driving between 1960 and 1973 than died in Vietnam.