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[Flare]

In any case, how fast do you people see this craft spinning anyway? I was under the impression that the large the craft, the slower it needs to spin in order to build up centrifugal energy.

[thobal]

I can easily see a problem with the 'whole station is rotating' idea.

Namely, it's be harder for something to dock with it. Not impossible, but a lot harder.
It's be like Elite. A lot of dying. Or at least, it would be like that with me.

Why not have the dock in the middle of the flywheel. The docking apparatus just needs to be place on ball bearings and a motor to counter act the small amount of friction and you now a stationary, self adjustable dock.

Lol, it's more complicated than that, dont forget to include a counter weight spinning opposite the main station with equal momentum or you'll start tumbling again. Oh yeah, and how do you propose to connect the spin section to the static section while keeping out the cold vacuum of space? You're gonna need some hella complex stuff.

[mainiac]

These are rather minor issues of design.  If they were insurmountable then we wouldn't have docking with the ISS, which also has to account for rotational correction.  If all else fails you could just have the spacecraft fire a maneuvering jet so it matches the .5 rpm speed of the station before docking.  Personally I can envision several more efficient ways then that but none so easy to explain.

Just because you can't immediately understand something doesn't mean it can't be designed.

[thobal]

These are rather minor issues of design.  If they were insurmountable then we wouldn't have docking with the ISS, which also has to account for rotational correction.  If all else fails you could just have the spacecraft fire a maneuvering jet so it matches the .5 rpm speed of the station before docking.  Personally I can envision several more efficient ways then that but none so easy to explain.

Just because you can't immediately understand something doesn't mean it can't be designed.

Plus,  if you don't want to have the kind of place where people are motion sick all the time, the rate of spin will be fairly low so docking on the spin axis wouldn't be that difficult. The trouble comes when you want telescopes and radio antenna stuck in one place.

And I'm gonna solve that problem with a system of mercury filled pipes and pumps.

Imagine the protests on such a place, a bunch of people gather in one place to overwhelm the mass compensator. The center of gravity/rotation would shift closer to them so they would experience less gravity while people on the opposite side would experience more.

[mainiac]

I don't think people would be a high enough percentage of station mass to do such a thing.

[thobal]

I don't think people would be a high enough percentage of station mass to do such a thing.

I know, but it's a fun thought.

[vadia]

These are rather minor issues of design.  If they were insurmountable then we wouldn't have docking with the ISS, which also has to account for rotational correction.  If all else fails you could just have the spacecraft fire a maneuvering jet so it matches the .5 rpm speed of the station before docking.  Personally I can envision several more efficient ways then that but none so easy to explain.

Just because you can't immediately understand something doesn't mean it can't be designed.

Plus,  if you don't want to have the kind of place where people are motion sick all the time, the rate of spin will be fairly low so docking on the spin axis wouldn't be that difficult. The trouble comes when you want telescopes and radio antenna stuck in one place.

And I'm gonna solve that problem with a system of mercury filled pipes and pumps.

Imagine the protests on such a place, a bunch of people gather in one place to overwhelm the mass compensator. The center of gravity/rotation would shift closer to them so they would experience less gravity while people on the opposite side would experience more.

In my life beyond the earth class the professor calculated that a ring with a mile radius would be pretty negligable -- after all you don't feel the spin of the earth. 
Each day it would need to make one rotation. -- not that big of a deal.  Many of the things you didn't want to have much motion on could be in the (virtually) weightless center.

[Flare]

Lol, it's more complicated than that, dont forget to include a counter weight spinning opposite the main station with equal momentum or you'll start tumbling again.

What do you mean? The dock at the centre of the ring will be able to turn at a different rate than the rest of the ship, spinning this part to the rate of the craft it's trying to connect won't require a counter balance. Once the ship is securely connected to this part of the dock, all you need to do ever so slowly put on the brakes. Using fuel for adjustments for these things is quite common. That's not to mention the on board gyros that help it rotate.

Oh yeah, and how do you propose to connect the spin section to the static section while keeping out the cold vacuum of space? You're gonna need some hella complex stuff.

I don't think you quite understand how the design works. Imagine a donut- the rotating craft, and inside of this donut parallel to it is another donut. This donut has ball bearings and can spin in another direction if it needs to, much like how the axles on a car can spin to allow the wheels to go round, and not have the rest of the car flipping with said wheels. All you need to do once the ship attached itself to the dock and once slowed down is to simply use the same mechanism the ISS uses to connect two craft together inside of this dock.

Suppose the space craft comes in with its nose into the dock. Once it spins in unison with the rest of the rotating craft, all you would need to do is to push forward the tube inside of the ball bearing donut to the hatch of the space craft.

But there's an even simpler way than this. If you have two ball bearing donuts on both craft. You can attach tubes to each other without having to spin together at all allowing for refuel and whatnot. Imagine a garden hose with a ball bearing screw tip so that you can spin the tube  connected to a gas tank that also has a ball bearing connection with the tube.

[vadia]

Lol, it's more complicated than that, dont forget to include a counter weight spinning opposite the main station with equal momentum or you'll start tumbling again.

What do you mean? The dock at the centre of the ring will be able to turn at a different rate than the rest of the ship, spinning this part to the rate of the craft it's trying to connect won't require a counter balance. Once the ship is securely connected to this part of the dock, all you need to do ever so slowly put on the brakes. Using fuel for adjustments for these things is quite common. That's not to mention the on board gyros that help it rotate.

Oh yeah, and how do you propose to connect the spin section to the static section while keeping out the cold vacuum of space? You're gonna need some hella complex stuff.

I don't think you quite understand how the design works. Imagine a donut- the rotating craft, and inside of this donut parallel to it is another donut. This donut has ball bearings and can spin in another direction if it needs to, much like how the axles on a car can spin to allow the wheels to go round, and not have the rest of the car flipping with said wheels. All you need to do once the ship attached itself to the dock and once slowed down is to simply use the same mechanism the ISS uses to connect two craft together inside of this dock.

Suppose the space craft comes in with its nose into the dock. Once it spins in unison with the rest of the rotating craft, all you would need to do is to push forward the tube inside of the ball bearing donut to the hatch of the space craft.

But there's an even simpler way than this. If you have two ball bearing donuts on both craft. You can attach tubes to each other without having to spin together at all allowing for refuel and whatnot. Imagine a garden hose with a ball bearing screw tip so that you can spin the tube  connected to a gas tank that also has a ball bearing connection with the tube.

simpler would be to dock in the middle -- there isn't any "gravity" there but the spin isn't significant either.  After all It's a thing the size of an apartment complex that spins around once a day. 

The shape would be doughnut with a thin stick in the middle.

[GreatWyrmGold]

I don't think people would be a high enough percentage of station mass to do such a thing.

Technically, it would work.
Practically, it wouldn't do much.

I can easily see a problem with the 'whole station is rotating' idea.
Namely, it's be harder for something to dock with it. Not impossible, but a lot harder.
It's be like Elite. A lot of dying. Or at least, it would be like that with me.

Why not have the dock in the middle of the flywheel. The docking apparatus just needs to be place on ball bearings and a motor to counter act the small amount of friction and you now a stationary, self adjustable dock.

Friction. Unless you want to spend a load of fuel keeping the station rotating, the central part will, eventually, slow down the whole station.

I would have thought that, no matter what, the whole station would stop rotating after a while. I brought this up earlier, and it wasn't addressed.
If my reasoning is off, my Sci-Fi will be much more interesting...

[mainiac]

Why not have the dock in the middle of the flywheel. The docking apparatus just needs to be place on ball bearings and a motor to counter act the small amount of friction and you now a stationary, self adjustable dock.

Friction. Unless you want to spend a load of fuel keeping the station rotating, the central part will, eventually, slow down the whole station.
[/quote]

Friction doesn't work that way.  The station as a whole keeps it's angular velocity so it returns to its configuration if you reset the position of the dock.  The only change possible is when a craft docks with the station.  That would be a tiny change and could be offset when the craft launches.

[mainiac]

I would have thought that, no matter what, the whole station would stop rotating after a while. I brought this up earlier, and it wasn't addressed.

Because it's so obvious that it's hard to find the words to address it.  An object rotating in a vacuum doesn't stop rotating after a while.  What do you want us to say?  Take physics 101?

[vadia]

Why not have the dock in the middle of the flywheel. The docking apparatus just needs to be place on ball bearings and a motor to counter act the small amount of friction and you now a stationary, self adjustable dock.

Friction. Unless you want to spend a load of fuel keeping the station rotating, the central part will, eventually, slow down the whole station.

Friction doesn't work that way.  The station as a whole keeps it's angular velocity so it returns to its configuration if you reset the position of the dock.  The only change possible is when a craft docks with the station.  That would be a tiny change and could be offset when the craft launches.

No, he's on about the central part remaining stationary i.e. no rotation whilst the rest of the station rotates. There would have to be at least one part of the non-rotating part of the station touching the rotating part, leading to friction between the non-rotating part and the rotating part. This would lead to either:
A) The stationary part rotating with the station or
B) the rotating part of the station becoming stationary

So you'd have to keep expending energy preventing the friction from counteracting what the station is doing. You could have the central part rotate with the station until a ship gets close, but that only minimises the friction, it doesn't remove it.

It isn't stationary.  It rotates, just very slowly.  It would be like a full rotation of an apartment building once a day. 

You wouldn't notice it any particular minute, but after an hour you'd have noticed the difference.

If it were just over 300 feet it would be moving 1000 feet a day or about 42 feet an hour .7 feet an hour and about .01 feet a minute.  There are a lot of clocks with minute hands that move faster than that.

[Thecard]

Any change in speed will result in friction.  That's just how it works.
I think.  I'm not a physics kinda guy though.

[vadia]

Any change in speed will result in friction.  That's just how it works.
I think.  I'm not a physics kinda guy though.

There will need to be corrective measures occasionally, but it shouldn't be as much as one launch from mars for hundreds of years.
And if there is anything that the colony wants outside of mars minerals they have to have it shipped in or send a ship out.

A launch from the station takes about the energy of you pushing it.

In fact scientists often describe the orbit around the earth as 50% of the way to the whole universe jokingly because of the energy it takes to leave the gravity field.