Is a Centrifugal Space Station Scientifically Possible ?
I have pondered over this theory for many years and I just don't seem to see how it could work. If you are in 0 gravity and no outside force is influencing you how are you supposed to stick to the wall. Wouldn't you just float in the middle as desks, computers and file cabinets wiz by you that are bolted to the floor. I don't see how Objects moving around me are going to effect my mass. The only thing that would be touching me ( barring a file cabinet doesn't smack you in the head on it's way around ) is the atmosphere inside the station. As far as I know the atmosphere is not affected by the gyroscopic forces created by the spinning station in a way that would make my mas stick to the floor similar to the effects of gravity. What am I not getting here? Why isn't the Centrifugal Space Station like a giant blender? Or do I have a point?
2012-07-15T18:47:33Z
I have been to amusement parks and ridden on rides such as the Gravitron but these rides are under the influences of other forces, mainly gravity. What I don't understand is if I am not touching the floor of the space station how is MW2 R and W going to affect M. These factors are only going to affect me if I am not touching the space station. Take into consideration this works and I start holding on to the floor. What happens if another force pushes me ( such as a pipe in the wall breaking god forbid forcing high velocity force ) and changes my speed with the speed of W?
2012-07-15T18:50:27Z
Sorry, typo. I meant to say: This will only affect me if I Am touching the space station.
Randy P2012-07-15T17:53:54Z
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Sure, why not? That principle is used for amusement park rides all the time, it works just fine. And for the device called a centrifuge.
From the standpoint of something inside the space station, you are being pushed against the walls with a force mw^2 r where m = your mass, w = the rotational speed in radians per second and r = the distance from the axis of rotation.
What is actually happening is centripetal force. Without the presence of the space station, you would float in a straight line. But the walls of the space station continually press against your feet to push in you in a circle. That feels like weight to you, and it acts like weight. The same force is acting on air and anything else. The force gets weaker as you get closer to the center, becoming 0 when r = 0.
It certainly works as the others have already said. F = m w^2 r if w and r are held constant then F = m "g" just as we have here. It seems like gravity until you do some experiments.
For example. If you try to play pool the balls curve as they move along the flat surface. If you try to throw a ball to a friend it curves in the air.
I have done these experiments on a merry go round here on earth. If I get it right I can throw a shoe to my right, it circles in the air like a boomerang and returns from my left. Quite fascinating. You should try it some time.
If you have to climb "up" ie towards the centre of the station then the gravity reduces. So such a station is constructed as a doughnut keeping all the working parts at the constant distance r from the centre.
Due to the relative friction everything must soon move with the same tangential velocity as the station. Initially the air will lag behind as you accelerate the station. But friction between it and the walls will soon dampen out the relative motion.
The atmosphere is most certainly affected by the forces but nowhere near enough to raise it to our pressure. We have gravity acting on a column of air many kilometres high to give our pressure. On the station there is only a radius of perhaps a hundred metres or so. Not enough to give significant air pressure from this source alone.
But the forces on any piece of air ( eg a balloon) are still identical to those on the same balloon on a planet with the same value of g.
The key to the station is to make it big enough so that the rate of spinning ( w ) is low and does not produce significant disorienting effects for normal activities.
Centripetal acceleration is a very practical implementation of artificial gravity. One does even need to make the space station ring-shaped; it can just be a single capsule with a counter-weight. Let r = the radius from the center of rotation Let V = the tangential velocity of rotation Let a = the acceleration = 9.8 m/s² a = V²/r The vehicle could use thrusters like the reaction controls on the shuttle to start it spinning at the right speed and would require occasional adjustment, when mass is added or subtracted from the space station. Also, it does not matter what the orientation of the rotation with respect to the orbit. This future design could have a center area the acts like an axle where all of the solar panels and antennas are mounted, because it is better to have them not rotate.
Take a look at the entire earth itself. It is in a net zero gravity environment. But since the earth can generate gravity, we don't go flying off the surface.
But take a round space station, tubular in shape. As it spins, you and everything inside spins at the same speed. Newton's law says that anything in motion will continue in a straight line until something interferes with that movement. In this example, the inside wall of the space station will hold you against the outside perimeter of the space station. Just like the spin cycle of the washing machine. As long as the spin is maintained, the clothes will "stick" to the sidewall of the tub. The earth's gravity has no effect on it. So a spinning space station is like the inside of a spinning wash tub but the walls of the tub will actually be the "floor" that you'll walk on and work on. Internal friction will cause you to rotate with the space station so you can't "float"..
OS, you really need to go to an amusement park where they offer the rotating barrel as a ride. Here they start out with the riders at the bottom of a gigantic barrel; they are lying down on the floor of the barrel.
Then the barrel starts to rotate. Slowly at first, but it picks up rotational speed. The riders rotating around in the bottom start to slide outward towards the vertical sides of the barrel. They are sliding towards the sides because of centrifugal force, from which your CSS gets its name. This is the same centrifugal force that forces you to the outside of a turn as you round a corner at high speed in your Ferrari.
As near top rotational speed, the centrifugal force has smooshed the riders up against the wall. There the riders do what they can to flatten out against the walls. Once everyone is in place, flat against the walls, the floor bottom drops out...leaving the riders pinned against the walls with no visible means of support. The centrifugal force is enough (coupled with friction against the wall).
And those riders don't move much. They are way heavier than normal because the centrifugal force is greater than the normal force of gravity. Then the floor pops back up and the barrel rotation starts to slow down. At a certain point the friction force and centrifugal force are no longer able to hold the riders against the wall and they slide back to the floor. The ride ends there and the riders stagger off the barrel to tell their family how they survived the ordeal.
And that's how it is in the CSS. It rotates to create a centrifugal force about equal to normal gravity force. And as there is otherwise zero net gravity force (net weight), the centrifugal force is the only force acting on the crew...and their desks. But the crew and the desks are rotating at the same rate. So the desks are not moving relative to the crew.
To enter and exit the CSS, the crew go into and out of the center, the axis of rotation. There, because the radius of rotation is zero, the centrifugal force is also zero. So they grab a guy wire and pull themselves outward toward the edge of the rotation station where, because the rotation radius is now large, the centrifugal force is now large. They drop their feet to the wall of the CSS, which is the floor while rotating, and there they are...rotating around at the same rate as the desks and chairs.