Babylon 5's Rotation

[FalTorPan]

The bulk of Babylon 5's habitable spaces rotate about the station's longitudinal axis to create a gravity-like effect. Question: what keeps the "non-rotating" section of the station from seeming to rotate in the opposite direction? On the TV show, the fusion reactor and spine always seem to be at the "top."

Seems fishy to me, but I haven't studied physics in nearly a decade. Sci/Tech experts, what sayeth thee?

 

[Alpha_Geek]

Some type of thruster system, insane amounts of mass, gyros, something yet to be invented...or pfm? :-)

AG

 

[flux_29]

a generator fimply tuning it.

 

[Outpost4]

Squirrels. Gigantic intra-galactic squirrels, weighing in at 800 pounds each and with legs like a grizzly bear, galloping on a giant wheel.

 

[Brent]

simple, the "camera" was always positioned to view it that way so it'd make sense to us

while in reality it could have been spinning the opposite way

 

[Timo]

Umm, the spine stayed stationary with respect to the planet on the background. So yes, it was spinning the opposite way to the bulk of the station. But only just enough to make it stationary.

Nothing wrong with that kind of an arrangement as such. Communications and weather satellites around Earth used to do it a lot, in the days when they were all spin-stabilized rather than held in the proper orientation by internal gyroscopes. They would have a cylinder body covered in solar cells, rotating enough to serve as a source of gyroscopic stability. And then they would have a little motor that would spin the antenna or camera cluster the other way, so that they would end up remaining stationary and pointing at Earth.

There would be no particular advantage gained from having the spine and reactor part of B5 spin in the opposite direction at a faster rate than the "just enough to cancel out movement" one we see. Indeed, the whole point of this counterspinning is to make the spine "immobile" so that it can receive zero-gee shipments and keep comm antennas and guns and sensors pointed at things and so forth.

Then again, B4 as seen in the time travel two-parter apparently had sections that spun against the habitat bulk at double the spin rate of this bulk, so effectively they spun in the opposite direction even with respect to the background. Hard to tell why. The two spins wouldn't "cancel out" any torque forces or anything. They'd just be a nuisance in the end.

Timo Saloniemi

 

[David cgc]

Actually, both of Babylon 4's rotating sections rotated at the same rate, in opposite directions, relative to a nonspinning frame. I believe the idea was, in fact, to cancel the gyroscopic forces of the rotating section and allow the station to maneuver.

 

[Timo]

Yup. But it doesn't work quite that way. If you have two counterrotating sections on the same axis, and try to twist the thing, you actually get twice the gyroscopic problems - the forces may "cancel out", but they do so by putting twice the stress on the "hinge point". Trying to pitch or yaw B5 would call for strong thrusters that cancel out the precession (or then for clever maneuvering that allows for the precession). Trying to pitch or yaw B4 would call for superstrong construction materials.

Timo Saloniemi

 

[Brandonv]

Timo said:
Trying to pitch or yaw B5 would call for strong thrusters that cancel out the precession (or then for clever maneuvering that allows for the precession).

Timo Saloniemi

I guess the Omega Class Destroyers would have the same problem then.

I've always thought that the Omega Class Detroyers are cool looking ships, but maneuvering them must be tricky.

 

[Manticore]

That's probably one of the reasons that Earthforce wanted artificial gravity so much.

 

[flux_29]

Brandonv said:

Timo said:
Trying to pitch or yaw B5 would call for strong thrusters that cancel out the precession (or then for clever maneuvering that allows for the precession).

Timo Saloniemi

I guess the Omega Class Destroyers would have the same problem then.

I've always thought that the Omega Class Detroyers are cool looking ships, but maneuvering them must be tricky.

but wouldn't they increse the rate of the centrifuge thrusters to keep pace.

 

[Neopeius]

flux_29 said:

but wouldn't they increse the rate of the centrifuge thrusters to keep pace.

The centrifuge produces gravity at *right angles* to thrust. So it makes no difference how fast they spin. ^_^

Most likely, the Earth Force engines were just pretty slow drives.

 

[Timo]

They wouldn't have to be capable of much acceleration, because interstellar travel is by jumpgate or internal jump drive anyway. Interplanetary jaunts would benefit more from sustainability of the drive than from great accleration.

And combat involves spitting out a mixture of homing and unguided fire that apparently cannot be evaded even if you accelerate a lot. However, since the seeming main weapon of the Omega is that badass beam gun that only fires dead ahead, it's a rather fatal drawback that the ship can't turn fast!

Of course, nothing unrealistic about that. Warships in the late 19th and early 20th centuries were floating fatal drawbacks, due to the rapid development of weaponry and protection at the time. Earthforce could be in the same jam at the time of B5, operating the least useful ships in the universe - yet developing tactics that make them marginally useful nevertheless.

Timo Saloniemi

 

[Brandonv]

Timo said:
However, since the seeming main weapon of the Omega is that badass beam gun that only fires dead ahead, it's a rather fatal drawback that the ship can't turn fast!
Timo Saloniemi

The beams can fire at angles and can be swept in a kind of "slicer" mode, so I think the Omegas should have a reasonably large cone of fire, as long as they keep their distance. In one episode you can also see an Omega firing aft beams at a pursuing ship.

 

[David cgc]

And in "Endgame," you can see an Omega pivot it's main guns downward. The design is similar enough to the little turrets that they can probably also shift side-to-side as well.