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Space Science

Skyhook Robot Passes 1000 Foot Mark 325

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. "
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Skyhook Robot Passes 1000 Foot Mark

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  • by Anonymous Coward on Sunday September 25, 2005 @06:21PM (#13646726)
    117,407,136 to go
    • by Anonymous Coward on Sunday September 25, 2005 @06:33PM (#13646788)
      er, UP, I meant UP!
    • A journey of a thousand miles begins with a single step.
    • Yea but it sure beats making one that goes in the atmostphere and failing at 3000 feet having wasted billions of dollars. Most of us here are on slashdot are mainly in computers and we expect all technology to move as fast as computer technology does. While in fact it doesn't Moores Law doesn't apply to everything just computer speed. If Computer Science did go at the speed of normal science I bet we will have less bugs in todays software.
      • Re:1000 feet down... (Score:4, Informative)

        by WaterBreath ( 812358 ) on Sunday September 25, 2005 @10:30PM (#13647798)
        Moores Law doesn't apply to everything just computer speed

        It doesn't even apply to that. It applies to transistor density. And, now more than ever, speed gains aren't directly proportional to transistor density increases.

        So your point might even be stronger than you intended it to be.
    • by Julian Morrison ( 5575 ) on Sunday September 25, 2005 @06:42PM (#13646833)
      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.
      • by Anonymous Coward on Sunday September 25, 2005 @07:17PM (#13646996)
        Look ma, I made it across the pool in an inner tube. I'm going to try the Pacific next!
        • Assuming that you're a robot with sufficient power reserves, that's pretty much the way it works. Especially if you're only planning on going across during good weather with those early models and slowly make them more rugged.

          Most robot submersibles start their testing in a pool. Then they chuck 'em in an ocean.

          --
          Evan

      • If this doohickey can climb 1000 feet it can climb a hundred million, assuming the battery holds out.

        Of course, then why test 300 meters? Just hang a line from the ceiling; if it can climb 3 meters it can climb 300.

         
      • by MindStalker ( 22827 ) <mindstalker@[ ]il.com ['gma' in gap]> on Sunday September 25, 2005 @07:22PM (#13647031) Journal
        Actually battery power wouldn't hold out. Current idea is to beam power through lasers. This technique is known to work well with fixed points but could produce problems if tether bends and sways with wind like it did in this test.
        • Wouldn't it be possible transmit the power through the cable itself? Or are there some major disadvantages that preclude it from being used?
          • by pete-classic ( 75983 ) <hutnick@gmail.com> on Sunday September 25, 2005 @08:00PM (#13647206) Homepage Journal
            As I understand it we're talking about a carbon fiber composite ribbon. You certainly couldn't run an entire circuit through it. If it were pure carbon fiber you could probably run half the circuit through it, but the polymers holding the fibers together would probably make this impractical.

            The weight and resistance of a wire are proportional to it's length. The resistance of a wire is inversely proportional to its weight.

            You understand this thing is going to be, perhaps 30,000 miles long, right? That's a 60,000 mile circuit when the lifting vehicle is at the far end (as for a moon or Mars mission).

            Weight and line loss would be two problems.

            -Peter
            • power distribution (Score:5, Informative)

              by j1m+5n0w ( 749199 ) on Sunday September 25, 2005 @11:32PM (#13648116) Homepage Journal
              As I understand it, single-wall carbon nanotubes range from being fantastically good conductors to being semiconductors depending on the type. Quoting wikipedia [wikipedia.org]:
              For a given (n,m) nanotube, if 2n + m=3q (where q is an integer), then the nanotube is metallic, otherwise the nanotube is a semiconductor. ... In theory, metallic nanotubes can have an electrical current density more than 1,000 times stronger than metals such as silver and copper.

              We currently build transoceanic fiber optic cables that can be completely powered from one end using DC power, with the ocean acting as ground (current technologies require a powered repeater every so often), so we have already built power cables within an order of magnitude of the required length (though the energy it would need to carry would likely be much much higher - a single crawler might use several megawatts continuously)

              I would be curious to know how a power cable on a space elevator would interact with the Earth's magnetic field. Would it impart a significant force on the cable? Would the cable need to be shielded?

              Alternatively, what are the power generation options in space? Could a nuclear powered crawler be built, and/or could power generation facilities be spaced at regular intervals along the cable?

        • by Hugonz ( 20064 ) <hugonzNO@SPAMgmail.com> on Sunday September 25, 2005 @08:53PM (#13647435) Homepage
          Current idea is to beam power through lasers...

          But then there's the issue of taking the sharks up there too....

      • I could get in my pickup and drive 1,000 miles today and not have any trouble. However, if I drove 100,000 miles, the engine would sieze up and the tires would blow out.
      • i beg to differ good sir. what about then this thing is another 100,000 feet in the air and it's freezing cold and the weight of the cable causes it to stretch. 1000 feet climb is NOTHING. hell there are plenty of existing cable cars that do exactly this same thing. it's a non achievement.
      • Publicity stunt (Score:3, Insightful)

        by uberdave ( 526529 )
        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.
      • by Eivind ( 15695 ) <eivindorama@gmail.com> on Monday September 26, 2005 @07:20AM (#13649360) Homepage
        If this doohickey can climb 1000 feet it can climb a hundred million, assuming the battery holds out.

        The battery won't and can't "hold out". The thing is, current day rockets consist basically of 90% fuel-tanks and fuel, along with maybe 5% engines and 5% cargo. That's how much energy is required to get to orbit. Offcourse most of that energy goes into lifting fuel.

        Batteries are atleast 2 orders of magnitude worse in energy/mass than rocket-fuel, and it gets significantly worse by the fact that batteries don't weigth less as they become decharged (a empty fuel-tank is ligther than a full one, nevertheless rockets jettison the empty ones and are multi-stage)

        rocket-fuel could do it, with amounts of fuel similar to those consumed by a rocket, but then you hadn't really won much, had you ?

        Current plans call for the climbers to be externally powered, perhaps by microwave or laser aimed at them from the ground. The energy delivered will go down as they get higher, but gravity decreases with the square of the distance to the center of earth too, so that works out ok.

  • by richdun ( 672214 ) on Sunday September 25, 2005 @06:24PM (#13646740)
    1000 feet? Nice, a "space elevator" (circa 2005) almost two-thirds the way to the top of the Sears Tower (circa 1973).
  • by Anonymous Coward on Sunday September 25, 2005 @06:25PM (#13646743)
    This makes my launch of my Estes Andromeda a successful test of intergalactic travel.

    • This makes my launch of my Estes Andromeda a successful test of intergalactic travel.

      Ah, the Andromeda was the first model rocket I built when I joined the model rocktry club in high school. Kind of miss those days. Funny thing is is that at the tyme I was living in Mass and when I moved back to Florida, less than an hour from the Cape, there wasn't any rocktry clubs there.

      Falcon
  • by Wazukkithemaster ( 826055 ) on Sunday September 25, 2005 @06:26PM (#13646752)

    If my elivator is in flight I think i'd decide that would be a good time to choose a religion.
  • 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.
    Hmmm....

    ~/Desktop/ $ units
    2084 units, 71 prefixes, 32 nonlinear units

    You have: 1000 feet
    You want: miles
    * 0.18939394
    / 5.28
    You have:
    cally@inego(23:24:09)

  • by thomble ( 642879 ) on Sunday September 25, 2005 @06:44PM (#13646849) Homepage
    ...Stairway To Heaven was looping on the Muzak. Frickin' annoying!
  • by Patermater ( 649067 ) on Sunday September 25, 2005 @06:45PM (#13646852)
    "This visionary concept would make use of an ultra-strong carbon nanotube composite ribbon stretching up to 62,000 miles (100,000 kilometers) from Earth into space." 62,000 miles?!?
    • Re:62,000 miles? (Score:5, Insightful)

      by MichaelSmith ( 789609 ) on Sunday September 25, 2005 @07:04PM (#13646932) Homepage Journal
      62,000 miles?!?

      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.

      • As long as they're going that far, why not just build it all the way to the moon? All the counterweight mass you need and then some, right there!
        • Dealing with the eccentricity of the moon's orbit is something of a pain in the butt. That gets easier to handle the less mass your counterweight has.

          By the way, who the heck links to articles on msnbc? That's about the worst news site on the internet. Not to mention, the article is just a mirror from the orginal [space.com] at space.com.
        • As long as they're going that far, why not just build it all the way to the moon? All the counterweight mass you need and then some, right there!

          Because the space elevator has to rotate at the same speed as the Earth. Otherwise it will quickly wrap its self around the Equator.

          The moon is in a 28 day orbit around the earth, so in one lunar orbit the earth would have wound the cable up entirely.

    • Yes. The ribbon has to extend past geosynchronous orbit in order for the counterweight to work. Mass of counterweight v. length is an engineering tradeoff.
    • Re:62,000 miles? (Score:2, Insightful)

      by Anonymous Coward
      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 fr
    • 62,000 miles?!?

      Or 17 times the distance between Paris and New York....

      Orbit is a WAY up there....
  • by popo ( 107611 ) on Sunday September 25, 2005 @06:46PM (#13646856) Homepage
    ... but isn't the cable the difficult part about building a space elevator?

    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 [jfold.com] if you ain't going to use it.

    • Both parts are tricky. The climber is "just engineering" but it does contain rather a lot of it.

      It needs to be externally powered (probably by laser or microwave from the ground), it needs to climb *fast* since capacity of the beanstalk is directly proportional to the speed of the climbers. (if the beanstalk can hold 10 climbers and they go 100km/h you can launch one every 2 weeks. If the climbers can do 1000km/h you could launch every 2 days on the same beanstalk.

      If you want to use it for space-tourism

  • by Mac Degger ( 576336 ) on Sunday September 25, 2005 @06:49PM (#13646865) Journal
    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.
    • Yeah.

      I want more videos like this [worldchanging.com]
    • Funds will have to be spent on this some day. Why should we wait until we do have a viable tether, and hold up construction then, when we can just as easily test climbers now, in parallel with trying to design a tether?
    • Actually, the mass production of carbon nanotube fiber is now a reality. Read for yourself here:

      Mass Produced Carbon Nanotubes [eurekalert.org]

      7 meters per minute!

      Future Hi [futurehi.net]

    • by cgenman ( 325138 ) on Sunday September 25, 2005 @10:45PM (#13647850) Homepage
      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.

  • by mark-t ( 151149 ) <markt AT nerdflat DOT com> on Sunday September 25, 2005 @06:50PM (#13646872) Journal
    I mean, it's all very well and good that CNT's may be able to THEORETICALLY provide the strength necessary for the cable, but you know there's always this annoying discrepancy between theory and practice. Afaik, they still haven't achieved the necessary strengths in lab tests.
  • Please, someone convince me of the economic viability of a 23,000 mile train journey. Not the technical viability, assume it can be done.

     
    • Re:White Elephant (Score:4, Informative)

      by John Hasler ( 414242 ) on Sunday September 25, 2005 @07:16PM (#13646992) Homepage
      Gigabytes have been written on the subject. Look it up yourself.
    • Re:White Elephant (Score:5, Informative)

      by Joe Random ( 777564 ) on Sunday September 25, 2005 @07:24PM (#13647042)
      As I understand it, most of the fuel that you expend in a standard launch is there to make sure that the rest of the fuel can make it high enough to finally push the payload into orbit.

      With a space elevator, you're no longer required to accelerate several dozens of tons (>90% of which is just fuel) up to 7 miles/second just to get a 500lb satellite in orbit. The cost savings would be huge.

      Now granted, you'll still have to haul some fuel up the elevator, but it's like the difference between climbing the stairs to reach the top of the Empire State Building vs. jumping to the top from street level in one bound.
    • Re:White Elephant (Score:4, Interesting)

      by tsotha ( 720379 ) on Sunday September 25, 2005 @09:34PM (#13647595)
      Well, launch costs to GEO are $10,000+ per Kg. If you could move up a couple of tons at a time while saving two orders of magnitude on cost, that's economic viability.
  • by pitc ( 557530 ) on Sunday September 25, 2005 @07:07PM (#13646944)
    "This lifter is much smarter than our previous versions. It's our 18th version..."

    Version 1 Logic: Go up.
    ...
    Version 18 Logic: Go up.

    ...?
    • by Mechcozmo ( 871146 ) on Sunday September 25, 2005 @07:23PM (#13647035)
      Version 1: Sits there
      Version 1.1: Has limited mobility
      ~
      Version 4: Moves in two directions. Left and Right. Damnit.
      Version 4.0.1: Rotated lifter. Moves up and down.
      ~
      Version 7: Plays elevator music in MP3 format
      Version 8: Moves along rope
      ~
      Version 9: Plays OGG files now
      Version 10: By eliminating the "WAIT 30" command we have increased speed by 30x
      ~
      Version 15: Now can read network drives for MP3, OGG, WAV, and AIFF files to play
      Version 16: Has sensor to look out for birds. Damn PETA.
      Version 17: Auto-updating kernel. We think.
      Version 18: Robot goes up.... Robot goes down.... Robot goes up.... Robot does down...
    • Version 19 Logic: Go up. Don't look down!
  • Bleh... (Score:5, Interesting)

    by RayBender ( 525745 ) on Sunday September 25, 2005 @07:08PM (#13646947) Homepage
    This is akin to saying that building a really nice looking command chair is a step towards a working warp drive in the starship Enterprise.

    The climber is trivial, compared to the cable. Wake me up when they have a cable that can hold 100 GPa and is longer than a millimeter.

  • by MBCook ( 132727 ) <foobarsoft@foobarsoft.com> on Sunday September 25, 2005 @07:13PM (#13646975) Homepage
    Found this one the company blog:

    I've been editing the video from the 1,000-foot robot test. Since I've been busy lately with grant writing etc., I wasn't involved in activities like making the ribbon. So it wasn't until I was watching the video that I noticed the sentence written in block letters on the 2-inch wide ribbon (which alternates color in 50-foot strips of bright yellow and fluorescent orange) near the top:

    ATTENTION PILOT: IF YOU CAN READ THIS, YOU'RE TOTALLY SCREWED.

    Our sense of humor (or at least Nyein's) may not (or it may) be visible from far away, but it's there.

  • correction (Score:5, Funny)

    by hikerhat ( 678157 ) on Sunday September 25, 2005 @07:14PM (#13646983)
    s/successful test of a space elevator/successful test of a balloon/g
  • ... and see if anybody invests.

    Although there are probably a good number of technical reasons for this test, it's probably about as much (or even more) a PR event as a technical test.

    Among other things, they still have to come up with a microwave power delivery system before this thing is really gonna fly -- not to mention the ribbon material (hopefully within a decade or two).

    • by drix ( 4602 ) on Sunday September 25, 2005 @08:23PM (#13647305) Homepage
      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.
  • by i41Overlord ( 829913 ) on Sunday September 25, 2005 @08:56PM (#13647453)
    The other day, while at a bar, I told people that I can jump over the moon.

    I'm proud to announce that today I jumped 2 feet- a critical proof-of-concept that demonstrates the feasibility of my claim. Maybe I'll be able to back it up after all!
  • by Baldrson ( 78598 ) * on Sunday September 25, 2005 @09:10PM (#13647508) Homepage Journal
    If you want to be rational about space elevators you have to face the fact that nanotube ribbons don't yet exist but ribbons made of materials like Dyneema or Spectra do. So what? Here's what [slashdot.org].
  • ADD (Score:2, Insightful)

    by Ranger ( 1783 )
    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!
  • There is a problem with the space elevator that I haven't seen discussed anywhere. If you have a space elevator you can't have any satellites at an altitude lower than or equal to the height of the elevator, since eventually they will run into the elevator with rather unpleasant results.
  • Series of balloons (Score:2, Interesting)

    by harves ( 122617 )
    From my limited understanding, the problem with a space elevator is essentially that the ribbon is kept tight (and under massive strain) due to it's length and the mass located out in space. So why not have a sequence of ballon mounted elevators (ie. one at 1000 feet, another from 1000 to 2000 feet, etc) allowing some slack in the ribbon? Once we get to a point where balloons are no longer feasible we can start using a real space elevator. The final "real space elevator" would no longer extend so far into t

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