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How do thrust gravity ships dock with space stations?


Aside from Tycho station because the ring is horizontal but how would they dock inside a O'Neil cylinder type station?

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Great question. It always bothered me that the movie 2001: A Space Odyssey claimed to be perfect in its depiction of science/physics, but on this point it was not. If you saw the movie and recall, the Pan Am ship docking with the rotating space station was itself rotating to enter the docking hub, which would be all but impossible and very subject to error and malfunction - also I don't recall Dr. Heywood Floyd spinning around inside the shuttle's cabin.

The point is that there should be some part of the station that is not rotating, or counter-rotating in an inertial frame relative to the outside world.

Where did you hear about O'Neil type stations? I read The High Frontier back in the 70's when it came out.

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Heard about O'Neil cylinders from Babylon 5, how would a thrust gravity ship dock with a B5 type station unless it changes direction and land on the hull, problem with rotating spaceships and stations as you implied what if a ship has trouble getting into the rotating docking port or crash into it.

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What would be "all but impossible" about matching rotational speed with the center of the space station? Especially with a computer-assisted control system.

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Why would that be your criteria. What if it can be done with computer-assist, but something is wrong with the computers? A massive solar flare fries everything, or a terrorist virus like the US put in Iran's uranium processing plant?
Instability or unstable equilibrium is bad engineering. You want systems that failover gracefully even in unpredicted situations.

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So by your criteria, the F-16 is a shitty fighter plane because it's inherently unstable and is only flyable because of the computer control built into its flight system. Never mind that it's one of the most successful fighter planes in the world, that the General Dynamics engineers deliberately made that design choice in order to make it more maneuverable and faster to respond, or that this choice has never been an issue in decades of service with 27 different countries -- needs a computer, piece of shit.

Nope. It's not that cut and dried.

Also, I am not conceding that computer assist would be necessary either, merely that it would routinely make it easier to match rotation. But matching rotation is actually a fairly simple thing, and I don't see why a good pilot couldn't do it. If Jim Lovell could manually correct the course of the Apollo XIII lunar module -- a much more dynamic and unstable situation -- merely by visually sighting the earth in the LEM's window, I think a decent pilot should be entirely capable of matching his craft's rotation -- it's slow rotation -- in a single plane with that of the space station, and then gently nudge the craft into the docking bay on maneuvering thrusters once he has so matched.

Yeah, I'm really scratching my head trying to figure out why you think this is an issue.

At all.

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#1. You're claiming no significant difference between translation and rotation in space and flying a jet fighter in the atmosphere. I don't feel like I have to respond to that it is so obviously not comparable.

You don't have to scratch your head, my reasons are right above and are very clear. What you are really scratching your head about is trying to come up with some kind of goofball way to win an argument you should not have started ... see #1

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Yeah, flying a jet fighter would be the more complicating thing in this instance. Flying a fighter plane is an extremely dynamic situation, a lot more so than the docking seen in 2001. That docking is NOT a complicated maneuver -- you maneuver to a fixed distance directly in front of the station's axis of rotation, you match rotation, and then you nudge forward with maneuvering thrusters to enter the docking bay, at which point no doubt a docking arm extends to secure your ship (this part is not seen on screen). And I cannot help but note that you don't seem able to provide and explanation for why it is so difficult. You insist that it is, but you can't explain why.

Well, sorry, but no. 2001 was made with technical assistance of Arthur C. Clarke, who no doubt forgot more about science, physics, and space travel than you or I will ever know. He didn't seem to see any problem with it.

On the other hand, adding a fixed section, as you insist would be necessary, means adding moving parts that will need lubrication, be subject to wear, be difficult to seal against loss of atmosphere, etc. Not to mention needing needing a huge flywheel, or have the second ring counter-rotate, because if you don't, your stationary part isn't going to be stationary for the same reason a single rotor helicopter needs a tail rotor so the whole aircraft doesn't turn opposite the rotor.

Or you could just have an approaching ship match rotation.

Gee, I wonder which approach is simpler?

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You are really just dense.
In space OBVIOUSLY there is less tolerance for slop.
You have no idea what Arthur C. Clarke had a problem with,
and he was Stanley Kubrick's employee, so he could only advice.
I doubt you have ever taken physics/mechanics or are any kind of engineer,
so like most folks here on MC you have no problem popping off about stuff
you have no idea about.

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And still no explanation. Sorry, if you can't explain it, you don't have an argument. Period. If you have an argument, make it. All I see so far is unsupported assertion, insults, and appeals to authority. None of which comprises rational argument.

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you just keep not accepting my explanation because you have no idea of the mechanisms involved, proven by your flippant companion to landing a jet. I doubt you have ever taken physics/mechanics or are any kind of engineer, so like most folks here on MC you have no problem popping off about stuff
you have no idea about.

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No I am not accepting your explanations, because you aren't providing any. Merely asserting something doesn't explain it. Merely asserting something and then saying "well you're too ignorant to understand" not only doesn't explain anything, it makes you look like an arrogant, condescending ass.

I don't believe for an instant that you have ever taken physics/mechanics or are any kind of engineer either, because if you had, or if you were you would be able to explain in detail why something is so, not merely assert that it is so. If you actually had the education to back up your self-righteous preening, you wouldn't be so obviously limited to self-righteous preening.

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I think they would dock at the hub? When they slowed and docked they would be low-thrust zero-g.

"Tycho station because the ring is horizontal"...not sure what you mean by that

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Usually with rotating ring space stations they are vertical like 2001.

Expense ships are build like skyscrapers, if they wanted to dock in a hub they would have to turn the ship in a vertical position.

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I'm not getting what you mean when you say horizontal or vertical with regards to the rotating rings.

I'm aware of the ships configurations, but if they're docking with the hub they are basically docking with a stationary object so they can orient any way they need to to have their airlock/port meet the station's hub.

I don't think in the show it's made clear how the rotating sections connect to the non rotating sections on Tycho, but from memory I think on the (ex)Mormon station there was a rotating hub corridor connecting to a non rotating section which is the setup you would need (or at least prefer) for spacecraft to dock.

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