|
|
|
|
|
|
|
|
|
 Posted: Mon May 08, 2006 8:24 am
Whenever somebody talks about the benefits of Colonising Space, they always seem to assume that there will be a constant supply of usefull energy for them (at this Solar Orbit, that's pretty much true), that bringing things on and off the Colony would be cheap and simple (as long as not all of it revolves, this is also true) and, as I have done myself until very recently... That Arteficual Gravity will be just like Planet-Bound Gravity, except that you'd be able to gauge it to whatever you want. No Technology which is so simple could ever give us such a complete solution as that; http://www.spacefuture.com/archive/artificial_gravity_and_the_architecture_of_orbital_habitats.shtmlApparently, there are many odd differences between Arteficual and "Natural" Gravity - some subtle and not for anyone but the designers of the Place to worry about, and some.... not so subtle - as in, they will have a tangible effect on your everyday life. As explained in the link, the Arteficual Gravity we like to think of, the "Design Gravity" (which is the Global Centripetal Acceleration - the Colony spins and everybody is pulled towards the outside), is not the only source of Arteficual Gravity we need to consider - there is also the Coriolis Acceleration, which happens when you move in the direction that the Colony is spinning - to the degree to which I understand it, if you run in the opposite direction to the spin at 9.81 meters per second (assuming 1 G Arteficual Gravity equivalent on the Colony), you'll float off the ground. That's about 36 kmph ~ 20 miles per hour. Obviously you're not gonna run at that speed, but the change in apparent Gravity from any suhc movement would probably be noticible to you. Note also that this doesn't have any effect as long as you are moving perpendicular to the rotation itself (from one side of the Colony to the other). Oh yeah, and it also mentions Relative Acceleration - I think it's talking about the different amounts of energy required to accelerate an Object depending on the speed at which it's already accelerating due to the Design Gravity. I'm not really sure if I have that one right, so... if anybody would like to explain it for me, I'd me most gratefull. In fact, that brings me to the real reason I've made this thread; I honestly don't know how these will affect the daily lives of the People who will live in such a Colony. I need your help here people. Discuss; Arteficual Gravity - the difficulties of making a Colony stable enough to withstand 9.81 outward Acceleration, the wierdness of living in an Environment where Coriolis Acceleration tells you whether or not you are moving "backwards" or "forwards" in the direction at which the Colony is rotating, the long-term affects of living in Arteficual Gravity for the people that live in it, whether or not you can be ******** with this kind of Physics.
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Mon May 08, 2006 10:57 am
now a couple of things didn't make sense for me. Consider the following classical centripetal acceleration equation:
a = v^2/r
say we have a space colony the shape of a torus with a radius of ~ 20km (this is rather large, but you said the effects are smaller for larger colonies). Ok so to have a centripetal acceleration of 9.81 m/s^2 , and thus a normal force which acts like like 1g, the velocity of any particular point on the outside of the torus would have to be
sqrt(9.81*(20,000)) = 0.022 m/s eek that's really small.
which means, that according to what you interpret the link is saying (haven't had a chance to read the whole link, it's a rather extensive report, but I've read parts) all you really need is 0.022m/s (which is slower than the average pace of a person) in the opposite direction of rotation to lift off. This, just doesn't make any sense.
I think we can assume that we are looking at it from the inertial reference fram of the colony, and therefore no change is really happening. Furthermore, if we move perpendicularily, and we have a change of 1km.
(0.022)^2*19000 = 9.196 m/s^2 -> so it's not that big a deal, esp since there's gonna be no 1km buildings. Say the building was 30 m though. then
(0.022)^2*19970 = 9.67 m/s^2 -> as for this, I don't know how we would feel a change of 0.015g.
However the effects of free fall are interesting, we were designing a space colony for a competition once, and we hadn't come upon that. so I shall look at it closer.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Mon May 08, 2006 6:22 pm
[ Message temporarily off-line ]
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Tue May 09, 2006 9:59 am
poweroutage which means, that according to what you interpret the link is saying (haven't had a chance to read the whole link, it's a rather extensive report, but I've read parts) all you really need is 0.022m/s (which is slower than the average pace of a person) in the opposite direction of rotation to lift off. This, just doesn't make any sense. Well, Vorpal has kinda given a good explanation of this as it is, but... lol, that equation would mean that the bigger the radius, the slower the city moves to maintain the same number of RPM. Which, erm... kinda doesn't make sense sweatdrop poweroutage I think we can assume that we are looking at it from the inertial reference fram of the colony, and therefore no change is really happening. Furthermore, if we move perpendicularily, and we have a change of 1km. (0.022)^2*19000 = 9.196 m/s^2 -> so it's not that big a deal, esp since there's gonna be no 1km buildings. Say the building was 30 m though. then (0.022)^2*19970 = 9.67 m/s^2 -> as for this, I don't know how we would feel a change of 0.015g. That's something I've also looked into - the affects of moving further towards the center of the Colony whilst the Colony still rotates at the same speed. Yeah, 0.015 G isn't gonna be felt by many people - that's all the more reason for having a very big Colony. poweroutage However the effects of free fall are interesting, we were designing a space colony for a competition once, and we hadn't come upon that. so I shall look at it closer. free fall? if you're already accelerated to 9.81, you'll end up landing in a different place than if you were to drop straight down - effectively following a curved path. Oh yeah, as a subtopic question.... why the ******** do I end up with so few replies on my threads on here? sweatdrop
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Tue May 09, 2006 2:52 pm
VorpalNeko, sorry for going haywire with the calculations. Rugged, give it time, the guild's new... it's a little slow right now. Only the big bang topic ended up going to second page. You also mispelled artificial.
edit: we're actually moving faster than most new guilds. so we're not doing so bad.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Wed May 10, 2006 8:07 am
poweroutage VorpalNeko, sorry for going haywire with the calculations. Rugged, give it time, the guild's new... it's a little slow right now. Only the big bang topic ended up going to second page. You also mispelled artificial. Yeah, lol, I noticed that.... sweatdrop poweroutage edit: we're actually moving faster than most new guilds. so we're not doing so bad. Ah, perhaps not so encouraging - I plan on making an RPing/Military Sci-Fi Guild soon.... Actually, would anyone here be interested in joining?
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Thu May 11, 2006 4:49 am
rugged Actually, would anyone here be interested in joining? Alas, Rping with guns is not one of my stronger suits.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Thu May 11, 2006 6:20 am
I have a love for rp'ing that comes only slightly before my love for eating broken glass, so alas, I too must decline.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Thu May 11, 2006 9:42 am
Chaotic Nonsense rugged Actually, would anyone here be interested in joining? Alas, Rping with guns is not one of my stronger suits. Oh, but your gun is no longer your most potent weapon with my Force; you're Suit of Powered Armour and your Ballistics Computer have taken over that role... smile Dave the lost I have a love for rp'ing that comes only slightly before my love for eating broken glass, so alas, I too must decline. Is your mouth ok? Lol, if it's not, maybe I have a chance... sweatdrop
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Thu May 11, 2006 8:00 pm
rugged poweroutage which means, that according to what you interpret the link is saying (haven't had a chance to read the whole link, it's a rather extensive report, but I've read parts) all you really need is 0.022m/s (which is slower than the average pace of a person) in the opposite direction of rotation to lift off. This, just doesn't make any sense. Well, Vorpal has kinda given a good explanation of this as it is, but... lol, that equation would mean that the bigger the radius, the slower the city moves to maintain the same number of RPM. Which, erm... kinda doesn't make sense sweatdrop Think of it this way... the total speed is the speed from the center of the colony. Which is technically moving slowler than the speed at the outer edge of the colony, since they must travel through the same angle at the same period of time. Also, (me just being lazy and not really reading the article at hand and just presuming here) must take into account that we are in zero external gravity, so once an object is set in motion, it is going to stay in motion unless blah-di-blah-di-blah you all know what i'm saying. So once the colony is set to its current speed... its going to stay that way, which is pretty cool since all you need to do to creat the whole 9.8 m/s^2 isn't that much work, since you can slowly apply it over time to the outer rim of the colony. With no friction to slow it down, any constant thrust done upon the outer rim of it will simply cause it to spin, the faster it spins to more the objects are drawn to the outer edges, effective giving the sense of gravity.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Fri May 12, 2006 8:00 am
ZuraiBarusk rugged poweroutage which means, that according to what you interpret the link is saying (haven't had a chance to read the whole link, it's a rather extensive report, but I've read parts) all you really need is 0.022m/s (which is slower than the average pace of a person) in the opposite direction of rotation to lift off. This, just doesn't make any sense. Well, Vorpal has kinda given a good explanation of this as it is, but... lol, that equation would mean that the bigger the radius, the slower the city moves to maintain the same number of RPM. Which, erm... kinda doesn't make sense sweatdrop Think of it this way... the total speed is the speed from the center of the colony. Which is technically moving slowler than the speed at the outer edge of the colony, since they must travel through the same angle at the same period of time. Also, (me just being lazy and not really reading the article at hand and just presuming here) must take into account that we are in zero external gravity, so once an object is set in motion, it is going to stay in motion unless blah-di-blah-di-blah you all know what i'm saying. So once the colony is set to its current speed... its going to stay that way, which is pretty cool since all you need to do to creat the whole 9.8 m/s^2 isn't that much work, since you can slowly apply it over time to the outer rim of the colony. With no friction to slow it down, any constant thrust done upon the outer rim of it will simply cause it to spin, the faster it spins to more the objects are drawn to the outer edges, effective giving the sense of gravity. Erm... yeah, I think we pretty much knew that already sweatdrop See, I was saying that Poweroutage's equations didn't make sense because she wrote them wrongly by accident... In any case, there will definitely be a lot of stress put on such a Colony if it was to be built and put into action. I suggest putting all the generators and factories and Shipyards into the massive central cavity of the cylindrical Colony - that way, only the stuff that needs Gravity is in the Cylinder.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Posted: Tue Aug 01, 2006 12:37 am
I don't think that the 9.8 m/s^2 acceleration is going to cause that much trouble in terms of structural integrity. In fact I'm sure the tension could be used to good effect as a means to keep the structure of the station strong. I agree that most of the heavy stuff should be kept towards the center of the station but this is more due to the fact that because the angular momentum of the station is conserved its rotation would slow everytime a mass got moved to the edge and would speed up when you moved something to the center. If we keep these masses small compared with the mass of the station like say about the mass of a human being at most then there shouldn't be too much of a problem. also however because we aren't moving masses out to the edges in a symmetrical way our station would begin to develop a bit of a wiggle about its axis and start to precess and all sorts of unfortunate things. A few minor correction thrusters should be enough to take care of it so long as we constantly monitor the orientation of the station and we keep the masses that transit out to the edges and back small.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
