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Artificial gravity!

  1. Dec 19, 2006 #1
    I've heard some great stuff about artificial gravity. The different ways it could be achieved. So far, I've heard that it can be done by rotation (reaching momentum), magnatism, keep accelerating something like a spacecraft so that people inside it sticks to the back side of the craft (assuming that it is ALWAYS in acceleration), adding extreme mass, or a gravity generator.

    Are there any other ways?

    I'm guessing rotation is the most cheapest way to make artificial gravity. How come ISS haven't developed this yet... all they need to do is spin... :rofl:
  2. jcsd
  3. Dec 19, 2006 #2


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    Why would they want artificial gravity? :tongue:

    And besides, it's hard to dock with a spinning space station. :wink:
  4. Dec 19, 2006 #3
    Why WOULDN'T they want artificial gravity? People live on the ISS for months at a time. Almost everyone who goes in outer space has some kind of space sickness. If you wanna know more about that, I found a good link that sums it up.


    If our future lies out there, we won't be going much further if we keep vomiting all over every spacecraft that leave earth. I heard that one way they solved this problem is by putting exercising machines on the spacecraft. Still, why don't they just design the spacecraft so that they could be rotated when it is in space so that they provide AG and prevent space sickness.

    I do agree with you about the docking part though, Hurky. lol

    I still wanna know if there are other ways to create artificial gravity and if there are, is there any other method cheaper then just rotation.
  5. Dec 19, 2006 #4
    Actually, NASA originally had plans to include a smaller scale version of "artificial gravity" onboard the ISS. It was called the Centrifuge Accommodations Module (CAM) but it was cancelled due to the station's (as expected) cost overruns.

    Besides, if the goal for including artificial gravity is to maintain healthy levels of muscle mass/bone etc for the station crew then it was would far easier (engineering-wise) and cheaper to build a rotating module within the station wherein the astronauts step into at regular intervals and get their conditioning, as opposed to rotating the entire station. A gym with a spin, if you will.

    The research benefits of having a science lab in a micro-gravity environment is pretty much negated by spinning the whole station.
  6. Dec 19, 2006 #5
    Velcro on the bottom of astronaut slippers and a "hairy" surface on the station floor. That is if the crew can stand the constant tearing noise made by the velcro action.
  7. Dec 19, 2006 #6
    LMAO, imagine that...
    With all the cutting edge technologies that we are using to save lives and protect humanity. Our only solution to cheap artificial gravity is velcro...
    Talk about a breakthrough! :bugeye:
  8. Dec 19, 2006 #7
    Well, we are talking about NASA here so cutting-edge is expected.

    I predict the breakthrough will come in the form of velcro that makes no tearing noise when the two layers are seperated :)
  9. Dec 19, 2006 #8


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    Couple of things:

    1] The engineering that built the ISS is way inadequate. The ISS would fly apart into a million pieces. The solar panels alone would be toast.

    2] Making a space station that is BIG enough to spin so as to provide AG is beyond our current ability. The ISS is only 240x150feet and most of that is solar panel, only a small fraction is habitation. That small fraction can't simply be rotated to provide gravity - you need to have habitation areas that are HUNDREDS of feet or more from the centre of mass, otherwise you get ridiculous rotation rates.

    3] Even if you take into account the above two factors, you STILL don't get rid of vomiting. The Coriolis force over these short distances is possibly as bad as zero gravity. You need a space station that MANY HUNDREDS of feet in radius to eliminate the feelings of disorientation.

    There is theoretically nothing we can't overcome, even with current technology. But it would be a vast undertaking that, as a project, would make the ISS look like a balsawood airplane.
  10. Dec 19, 2006 #9


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    The ISS isn't the right shape for that.
  11. Dec 20, 2006 #10
    I don't think that's even considered a form of artificial gravity. It's not pulling on any part of the body other then the foot. Not very gravity-like.
  12. Dec 26, 2006 #11
    NASA's next mission:

    ISVS: INternational Space Velcro Station.

    ( Hey, SimplePie go get the patent, NOW!!!!)
  13. Dec 27, 2006 #12
    LOL the movie garden state
  14. Jan 4, 2007 #13
    I don't know why people haven't thought of a big wind tunnel that blasts air and any objects in the vicinity towards a wall. No centripital force required:rofl:
  15. Jan 4, 2007 #14


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    Ooh, nice -- the wind can blast me against the wall, and my chair, and my desk... and my papers... and my paperweight... and sharp, pointy objects... :surprised

    (Why wouldn't I have a paperweight in a zero g environment? :uhh:)
  16. Jan 4, 2007 #15


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    If they really want exercise, they can dress up the cosmonauts in thick rubber suits (gimp suits, if you will). They'll make big efforts to bend the joints, which should keep them fit.
    This way, they'll save on heat bills too!
  17. Jan 4, 2007 #16

    Well i think its a decent idea... maybe not the best idea but still....
  18. Jan 4, 2007 #17


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    I think that a bunch of cosmonauts spinning and jumping off the walls of any space station would hurl it out of orbit .. into deep space or into the atmosphere.

    ...without proper "get back on course" mechanisms, that is :)
  19. Jan 5, 2007 #18
    Centrifuges tend not to work for a number of reasons. The engineering, for one. It's immensely difficult and immensely expensive to produce such a structure, especially since it all has to be launched into orbit.

    Second is that the radius has to be long enough so that the tangential acceleration experienced by the occupant at one's feet is roughly equivalent to the tangential acceleration at one's head. Building vertically would only worsen this phenomenon.

    Third is one of the worst of all, the Coriolis effect. To not experience the side effects(for lack of a better term) of the Coriolis effect, the centrifuge would have to spin at an angular velocity equalling 2 rotations per minute or less. It is thought that most humans can grow accustomed to more rpm's, but even the most adaptive of spacefarer cannot handle more than 7 rpm's.

    This would mean that a viable space habitat would need a radius of around a kilometer and a half.
  20. Jan 5, 2007 #19


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    No. The station and the astronaut are a closed system. They can't affect the motion of the station from inside.
  21. Jan 5, 2007 #20


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    You're right.
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