Coriolis Station Physics

[Slawkenbergius]

Isn't it fairly trivial to implement the Coriolis force in a 'good enough' way? You just need to sum a force in the direction of the station's rotation, whenever something becomes detached from the floor...

If you wanted to go the extra mile and make moving things weigh differently when travelling with/against the station's rotation, you'd just have to sum a 'perpendicular' acceleration to them. Possibly got this wrong, but if you're travelling in the direction of rotation, you'd sum a negative acceleration (add to gravity) which would make you heavier, and travelling contra you'd sum a positive acceleration (subtract from gravity).

Generally you'd only need to do that on detaching from the floor. The only reason I could think for doing it on a moment-to-moment basis is if you wanted to simulate what it would be like driving a racing car on a rotating spacestation. Depending on direction of travel, you'd have more or less downforce on the track, altering handling.

Not at all sure what speeds are involved though as to whether you'd notice a difference. Also, I might be talking nonsense.

 

[Captain N]

Not complete nonsense, but I think rotating the entire system is still a simpler way to do it. No mumbo-jumbo, just spin it!

You'd have to implement walking characters in an orientation agnostic way anyhow, if you want to model things like zero-g environments and walking on "walls" using magnetic boots... and objects would have to respond to the accelerations of the environment if you want shipboard action to be realistic.

 

[Darren Grey]

I think any practical coriolis station* design would have most areas very compartmentalised to severely reduce the physics effects. No weird atmosphere turbulence, no odd perspective shifts, etc. It more practical this way.

*I like the term! Much nicer than some of the more techy terms, scientifically accurate or not. Scientific accuracy is not that relevant for everyday language.

 

[Captain N]

Well now you're using that as a general term and that's just wrong! Wrong I say.

 

[Dejay]

If you wanted to go the extra mile and make moving things weigh differently when travelling with/against the station's rotation, you'd just have to sum a 'perpendicular' acceleration to them. Possibly got this wrong, but if you're travelling in the direction of rotation, you'd sum a negative acceleration (add to gravity) which would make you heavier, and travelling contra you'd sum a positive acceleration (subtract from gravity).

Hey that would be cool! If you start running against the rotation fast enough, you become weightless and can drift around while the station floor is moving under you I'd love to see this implemented with the walking around expansion.

 

[NeilF]

So has anyone with the Alpha had a chance to try my suggestion to work out the size of this sucker?

Just fly:-
a) Along it and time it.
b) Fly across the rotating face and time the distance from edge/corner to middle (& double). Might take a couple of attempts.

But it should give a good approximation of the dimensions to tens of meters?

 

[NeilF]

Hey that would be cool! If you start running against the rotation fast enough, you become weightless and can drift around while the station floor is moving under you I'd love to see this implemented with the walking around expansion.

If you threw a ball at the exact opposite speed of rotation, it would appear to everyone inside to fly along and up (parallel to the ground) forever

 

[Ittiz]

If you threw a ball at the exact opposite speed of rotation, it would appear to everyone inside to fly along and up (parallel to the ground) forever

Assuming there is no air anyway. Otherwise the air flowing with the rotation of the station would drag on the ball and eventually cause it to "fall". It would go much further in one direction than the other though.

 

[Pyros]

No I don't. What is this information you speak? Indulge me.

Don't you know that the Bene Gesserit has genetically improved the human race in order to... ahhem, wait, that is another universe

/OT

Evolution in nanotechnology and genetics should be able to invalidate much of the "not very good effects" of extended zero G and space exposition.

 

[Shigawire]

Don't you know that the Bene Gesserit has genetically improved the human race in order to... ahhem, wait, that is another universe

/OT

Evolution in nanotechnology and genetics should be able to invalidate much of the "not very good effects" of extended zero G and space exposition.

Long live the fighters!

 

[Seboss]

Assuming there is no air anyway. Otherwise the air flowing with the rotation of the station would drag on the ball and eventually cause it to "fall". It would go much further in one direction than the other though.

This made football games aboard Coriolis pretty dull.

 

[mbabbs]

I can understand that people want to relive the good old days when docking was hard, and I think it's fine for a single player game. But in MP I really don't want to be waiting for people to learn how to dock. Realistically, if docking was such a dangerous and difficult procedure, no one would be allowed to fly unless they were ace pilots.

It would be nice to see more sophisticated traffic control than we have seen so far. Perhaps there is and I need to read more threads

From the videos I have seen so far there seems considerable risk of collision while docking which seems far from what you would imagine it would be. Obviously not all stations would be the same, just as not all airports are the same, but it would be interesting to see docking queues at busy stations, fines + loss of license for breaking docking rules, space station 'pilots' for larger craft, auto landing programs downloaded to craft.......

...I'm late to the forum though so its likely this has already been discussed...

 

[ste]

Docking was pretty hard on the original, but really you only did it a couple of times then used your docking comp, so eventually it didnt matter. It doesnt come any easier than pressing a button.

So I dont see a problem.

I remember the Amstrad version I think it was and the S sometimes popped up well before you got anywhere near the station and you pressed D and 3 seconds later your teleported to the spacestation. Not sure if that worked on other versions, I dont remember.

So no matter how they do it it wont be as easier as the original.

 

[Captain Zoe E Summers]

I had and I still have problems to understand centrifugal artificial gravity in space. Thanx to some videos I managed to understand it better and how it can work. But for me it is silly.
I dont know how exactly I can explain why it looks silly to me because my English is very limited. But Ill try if someone would want to try and explain it to me why everywhere it is shown in same way.

So to be able to feel any Gs in centrifugal station solution we must have speed of outside of that spinning circle. So from center we must use ladder and go from center to that outside ring.

But then I think that it would be hard to hold balance while standing on that outside ring that will act as "floor".
And moving in direction with ring movement would be different than moving opposite (different G force).
That is how I think about that artificial gravity solution.

In this video https://www.youtube.com/watch?v=9QuLgl2vKis guy using kerbal space program game tried to achieve that and explain all that centrifugal artificial gravity.

Here is real life experiment.
https://www.youtube.com/watch?v=2EHwT33YCAw

Here are another explanation of centrifugal artificial gravity with some examples used in movies.
https://www.youtube.com/watch?v=WdECeGRXIxQ

Here are some informations and examples of artificial gravity.
http://www.racetomars.ca/mars/ed-module/artificial_gravity/


What bothers me is that in most of that experiments about centrifugal artificial gravity is that they try to always put humans on outside ring. For me it is weird.

I wonder why they dont want to use solution that would make floors that would direct rotation force directly under human and giving him ability to hold balance without problems.

Here is pic that I created showing what I mean.

In my opinion option 2 is most reasonable.

There is no such force as centrifugal - it's just a label to describe something from a single objects point of view.

It's all just centripetal and angular velocities.

 

[Styggron]

If we had the actual official size of the coriolis I could do some maths to check. Some people have already from estimates I see.

 

[Mephane]

It would be nice to see more sophisticated traffic control than we have seen so far. Perhaps there is and I need to read more threads

Yeah, at the moment it is a bit weird. The station is super-strict with regards to landing pad allocation, but lets everyone fly in and out at their leisure basically. I had my fair share of almost-collisions right in the entrance. I hope eventually the stations will not only assign landing pads, but decide when you are allowed to fly in and out, too.

(Sometimes I have to wait a few seconds when I select the Launch option, but I never saw a pattern as to this being related to actual traffic.)

 

[Gauntlet]

I would prefer to call the big cylindrical stations "Rama", after the original idea from Arthur C. Clarke's novel by the same name.

Although 'Rama' was a 'live trap' targeting young space faring species rather than a spinning space station, I grant you the principle is the same though

 

[Y2K]

I've just worked out, because I could, the internal centripetal G of the Coriolis station and the station isn't rotating fast enough, or it's much bigger than previous estimates.

I assumed that the station was 1km in diameter, as per the original Elite manual.

One complete rotation takes about 80 seconds, about 4.5 degrees s-1

That gives:

Radius (R) = 500 metres
Angular Velocity (Ὠ) = 4.5 degrees s-1

Centripetal acceleration at the outside edge is therefore 0.315 G. Nowhere near enough for the 1G we're after - though it would be quite usable.

To achieve 1G at the outside edge, the Coriolis needs to be significantly larger at the current spin rate.

I've calculated it as follows.

Desired Centripetal Acceleration = 1G
Angular velocity (Ὠ) = 4.5 degrees s-1

Radius (R) = 1590 m

Thus, if the Coriolis is producing 1G at the outside edge, it's over 3km in diameter.

If someone could time the rotation more precisely I can give a more accurate figure.

It would also be interesting to see if people can estimate the size by some cooperative triangulation in the multiplayer, if you can put away your guns for a few moments...

Cheers,

Drew.

I was just about to say the same thing :/

 

[Jasper]

There is no such force as centrifugal - it's just a label to describe something from a single objects point of view.

It's all just centripetal and angular velocities.

http://xkcd.com/123/

 

[Parabellum]

If you feel the need to play with centrifugal speeds and radii, this SpinCalc tool is very useful. Originally posted by Captain N here

As a rule of thumb, anything higher than 2 revolutions per minute (RPM) may cause motion sickness in the crew. Remember, the radius defined in the calculations defines the floor level giving 1G. Anything beyond that point experiences higher G and vice-versa inside the same radius.

Drew's figures work well: 1590m radius, 0.74995 RPM, Tangenital Velocity 124.87022m/s and exactly 1G at the radius - giving diameter of 1G cylinder as 3.180km.

My hobby is designing rotating space stations. PM me if interested.