Why have none of the passenger transports rotating sections (artificial gravity)?
- Thread starter Astraeus
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Nemesis-T-Warlock
Banned
They would need to be mahoosive to have rotation work in that way and therefore need their own special docking or transfer systems.
Look at the size of the Imperial capital ships to see what's required for artificial gravity.
Bother said Pooh.
Um, ah yes this might work...
Anti gravity is possible, but the energy cost for a large space station to have it would be impractical, much cheaper to have them rotate.
Smaller ships have a smaller area that needs anti grav making it much more practical.
Now move along, nothing to see here
Um, ah yes this might work...
Anti gravity is possible, but the energy cost for a large space station to have it would be impractical, much cheaper to have them rotate.
Smaller ships have a smaller area that needs anti grav making it much more practical.
Now move along, nothing to see here
But in the lore of the elite universe there is no anti grav. That's why the imperial capital ships have the large rotating wheel in the center.
To get spin gravity on a ship small enough to fit through a docking port, you have to make the ring smaller. That means to get it to produce the same gravity, it has to spin faster to compensate. Aside from making the view out the window of you first class cabin nauseating, there's another problem.
The smaller the ring, shorter the distance from the centre of the ring to the surface you're standing on. The shorter the distance from the centre, the shorter the distance over which the "gravity" has to change from zero to 1g (or whatever you find comfortable). This is called the gradient.
In a big, slow spinning ring, the gradient will barely be noticeable. In a small, fast ring, the gradient may be so steep that you'll notice the difference between the gravity your feet are experiencing and the gravity your head is experiencing. I don't honestly know what that would do to the average spacefarer, but I suspect it would involve a lot of falling over and puking.
If we had Newtonian Physics (I am Nat saying I do) then you could accelerate everywhere and orientate the cabins as "down" toward the engines.
Docking would be fun, Superfast entry, while facing away from the station, pulling 1g.
Slim
PS. Sticky shoes and barf bags are cheaper.
Docking would be fun, Superfast entry, while facing away from the station, pulling 1g.
Slim
PS. Sticky shoes and barf bags are cheaper.
I agree, it's a little like airliner travel today. Practically it's uneconomical to provide niceties for short haul flights and journeys in ED take a fraction of the time that even a short hop to the continent would take from England.
Stack 'em high, port 'em cheap!
Rotational gravity
Here's a thought experiment for you:
If a hollow object rotates such as to provide a centripetal force equal to g at the perimeter, and you are in it, standing on the perimeter, and you drop the apple you are holding, what happens?
Does the apple fall? I started wondering this after reading Rama (Arthur C. Clarke), where there's a great big spaceship which has an ocean, kept in its place via 'rotational gravity'.
I thought: it may fall, if the atmosphere (if there is an atmosphere) is rotating in the same way. But why would it? It might, if the space is subdivided into rooms which push the atmosphere along with the rotation, or if there's a city with walls, or anything to keep the atmosphere moving.
But obviously, in a vacuum, the apple would stay where you released it until you hit it on the next go round (unless you gave it some impulse when you released it).
What I think, though, ultimately, is that rotational gravity IS NOT THE SAME as gravity, and you can't apply the same reasoning. Sure, you'll be able to stay on the floor, but you'll always be kind of falling forwards or backwards. And stuff you drop won't fall.
Big passenger ships for civilians would accelerate at one g half the way and decelerate at one g the rest of the way. That would provide real gravity. If we have our ftl frameshift drive, I dunno, but if we have that, we have so much control over 'frames' that we by definition can provide artificial gravity, whatever the lore.
At some point the physics breaks and we have to go with what is fun.
Edit: Of course, Wikipedia has a good article on this: http://en.wikipedia.org/wiki/Artificial_gravity
Here's a thought experiment for you:
If a hollow object rotates such as to provide a centripetal force equal to g at the perimeter, and you are in it, standing on the perimeter, and you drop the apple you are holding, what happens?
Does the apple fall? I started wondering this after reading Rama (Arthur C. Clarke), where there's a great big spaceship which has an ocean, kept in its place via 'rotational gravity'.
I thought: it may fall, if the atmosphere (if there is an atmosphere) is rotating in the same way. But why would it? It might, if the space is subdivided into rooms which push the atmosphere along with the rotation, or if there's a city with walls, or anything to keep the atmosphere moving.
But obviously, in a vacuum, the apple would stay where you released it until you hit it on the next go round (unless you gave it some impulse when you released it).
What I think, though, ultimately, is that rotational gravity IS NOT THE SAME as gravity, and you can't apply the same reasoning. Sure, you'll be able to stay on the floor, but you'll always be kind of falling forwards or backwards. And stuff you drop won't fall.
Big passenger ships for civilians would accelerate at one g half the way and decelerate at one g the rest of the way. That would provide real gravity. If we have our ftl frameshift drive, I dunno, but if we have that, we have so much control over 'frames' that we by definition can provide artificial gravity, whatever the lore.
At some point the physics breaks and we have to go with what is fun.
Edit: Of course, Wikipedia has a good article on this: http://en.wikipedia.org/wiki/Artificial_gravity
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No, by living on planets and revolving Stations all the time,
zero Gravity is a pure luxus and one of the unique exciting experiences of space traveling.
Rotational gravity is not gravity at all. Objects subject to centripetal force will "fall" (vacuum or not) in an apparently curved path - the place the object lands will not be the place that was under it when you dropped it. If the rotating structure were large enough objects could fall in spirals.
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It would be rather straightforward to engineer artificial gravity for any size ship.
Tether it to a counterweight (main fuel, stores, landers, quarters for unpleasant people, etc), and thrust till the main ship and its counterweight are revolving about their common center of gravity at the two ends of a taut line.
The "bolo" method has been considered for extended duration human spaceflight (like a Mars Hohmann transfer), and there's no reason in principle that it couldn't be used. Tethers of required strength and length for low artificial gravity aren't terribly heavy with current materials, and by putting RCS on both hab and counterweight mid-course trajectory correction burns could still be done without having to reel in.
Personally, if designing the Beluga (the cruise liner) for extended stays at tourist destinations, I'd put the main fuel tank, transport cargo hold, and the jump engine in a detachable counterweight module that attaches via a tether to several points on the "top" surface of crew/passenger quarters, which would contain life support, maneuvering thrusters and command deck.
Tether it to a counterweight (main fuel, stores, landers, quarters for unpleasant people, etc), and thrust till the main ship and its counterweight are revolving about their common center of gravity at the two ends of a taut line.
The "bolo" method has been considered for extended duration human spaceflight (like a Mars Hohmann transfer), and there's no reason in principle that it couldn't be used. Tethers of required strength and length for low artificial gravity aren't terribly heavy with current materials, and by putting RCS on both hab and counterweight mid-course trajectory correction burns could still be done without having to reel in.
Personally, if designing the Beluga (the cruise liner) for extended stays at tourist destinations, I'd put the main fuel tank, transport cargo hold, and the jump engine in a detachable counterweight module that attaches via a tether to several points on the "top" surface of crew/passenger quarters, which would contain life support, maneuvering thrusters and command deck.
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Unlike a warship where they have to live on the ship, passengers are only on the ship as long as your cargo is. With supercruise and hyperspace that's not enough time to warrant needing gravity.
Yes .. I guess I was trying to convey the weirdness of rotational gravity. People who have not thought about this seem to think that rotational gravity (correct term: centripetal force} is the same as gravity, as far as generally getting along is concerned. I just think it is worthwhile to consider exactly what rotational gravity feels like.
So, yes, I agree with everything. You also disabused me of the notion that vacuum vs atmosphere matters, which I should have reconsidered myself, since on reconsidering I agree that it doesn't.
Anyway, +1!
So, yes, I agree with everything. You also disabused me of the notion that vacuum vs atmosphere matters, which I should have reconsidered myself, since on reconsidering I agree that it doesn't.
Anyway, +1!
I wonder if it's possible to park on the inside of an Orbis Station habitat ring.
Just to clarify, only an object dropped will "fall" if the angular momentum matches (relatively speaking) the rotating station. Otherwise, is exactly like parking your craft half way between the hub and ring of an Orbis Station. At least until the support pylon whack you.
Here's a great video of someone creating an artificial gravity ring in Kerbal Space Program
http://www.youtube.com/watch?v=9QuLgl2vKis
Just to clarify, only an object dropped will "fall" if the angular momentum matches (relatively speaking) the rotating station. Otherwise, is exactly like parking your craft half way between the hub and ring of an Orbis Station. At least until the support pylon whack you.
Here's a great video of someone creating an artificial gravity ring in Kerbal Space Program
http://www.youtube.com/watch?v=9QuLgl2vKis
Aye it's interesting to think about. I'm guessing that you would adjust and not notice the difference most of the time especially on very large structures. You'd need to relearn how to play catch - a thrown object would behave in unfamiliar ways depending on the direction you threw it. Playing any kind of game involving judging vectors and such would be interesting
If the rotating cylinder were small enough could you jump off the "floor" and land on the "ceiling"? It would probably feel pretty weird if you were near the axis and your body was being pulled in opposite directions.