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Designs for a space station with artificial gravity

  1. Aug 7, 2013 #1
    I've been throwing around designs for a space station with artificial gravity for a while now and here is where its at in my head, the drawing is EXTREMELY crude but hopefully someone can understand the idea. the 2d drawing is meant to show a basic side view of it, the blue arrows indicating the gravity. the green showing which direction the craft would be spinning.
    the idea is that the centrifugal force from the spinning pushes you down and the inertia in the opposite direction of the spin, so the gravity should be between those two forces, at 45 degrees.
    this is almost definetly wrong but could someone please explain if this would work and if not, why? thank you! :)

    Attached Files:

  2. jcsd
  3. Aug 8, 2013 #2


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    The artificial gravity due to inertia would come into play only if the station kept accelerating its rotation. I'm pretty sure you don't want to do that, as it would result in constantly increasing "gravity" due to the centrifugal force. Eventually it would crush the inhabitants and tear the station apart.

    What you want, is a station rotating at a constant angular velocity. The only moment when "gravity" due to inertia would come into play is when the station is spun up to the desired velocity when constructed. Afterwards, it's only the centrifugal part that would generate artificial gravity, so you want the floors perpendicular to the axis of rotation. This means the station should be shaped like a ring(or cylinder), or sections of it.

    This clip from "2001: A space odyssey" shows one such design:
    Last edited: Aug 8, 2013
  4. Aug 8, 2013 #3
    of course! I didn't think of that!! thank you! so if a donut shaped station was rotating at the right speed, people would be pulled towards the outer edge of it? and there would be no gravity in the middle?? Thank you by the way!
  5. Aug 8, 2013 #4


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    Yeah, that's about right.
  6. Aug 8, 2013 #5
    Brilliant thanks!
  7. Aug 9, 2013 #6
    So why have there been no efforts to build a rotating space station? The idea has been around for decades through science fiction stories and movies, but not since the Gemini mission experiment has anything been done to use centrifugal force for artificial gravity. We know from the effects recorded by studies of ISS astronauts that the human body suffers many ailments once in zero G, some irreversible, so for long term space habitation or travel the rotating space stations would seem the only sensible solution. The only problem I could think of might be to do with surface charging problems, creating patches of varying charge levels sufficient to cause damaging electrostatic discharges, but I though they had that figured out already.
  8. Aug 9, 2013 #7


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    "Why are we not building railguns on the Moon? After all, it's the best way of sending back all that helium we harvest."

    Can you see my point?
  9. Aug 9, 2013 #8

    Filip Larsen

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    If you are interested in reading up on rotation induced artificial gravity you may want to visit http://www.artificial-gravity.com/ which has many references to various papers on the subject.
  10. Aug 10, 2013 #9
    no, I cant actually?
  11. Aug 11, 2013 #10


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    I was pointing out to Solon, that it's no wonder that this particular one(as well as any other) solution to a nonexistent problem is not being used.
    Once somebody starts to delelop "long term space habitation or travel", we might be able to discuss the merits of the eventual design.
  12. Aug 13, 2013 #11
    There are plans for a centrifuge demonstration on the ISS. While it hasn't been cancelled, it still hasn't been confirmed-

    Last edited: Aug 13, 2013
  13. Oct 28, 2013 #12
    There are some wierd effects of this kind of system, one effect is that, say the space station is rotating at a surface velocity of 10 m/s, then running retrograde at such a speed would result in getting stuck floating around.
    And of course, the crushing 4 Gs if you decide to run along with the station at that speed.

    Also, it should be possible to build a spinning parabola on Earth with the property that the force is always tangent to the surface.
  14. Oct 30, 2013 #13
    There are inherent problems with rotating space ships; that induce artificial gravity through centrifugal force.

    The most important of them is balance. If a person were to walk on the perimeter where the artificial gravity is strongest then his shifting mass will cause one side of the ship where the mass is greater to move towards that direction. Now if we add the spin then the ship will start with a cork screw trajectory and will get worse as the spin continues.

    The only way to counter this phenomenon is to have pumps pumping a liquid in the opposite side equal to the mass of the person or persons walking.

    Take a spinning top and add more weight to one side and you will see what I mean.

    I am not good at describing things but I hope you understand what I am getting at.
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