An often overlooked piece of tech in sci-fi

[Lord of the Abyss]

If you're talking AG there's another can of worms in the form of inertial dampeners. Creating 1G is one thing; nullifying hundreds or thousands of G-forces is something else entirely.

Arguably they're very similar problems; it's "just" a question of cranking the power up by a few orders of magnitude.

An extremely powerful AG field pulling everything on the ship 'up' towards the nose, synchronized with a drive pushing it from 'below' at the tail, would be a relatively elegant way to avoid inertia from high-acceleration thrust.

Charles Sheffield called that technique the "Balanced Drive"; in his case it was a disk of collapsed matter at the front of the ship producing the gravity, and the habitat capsule was mounted on a pillar extending from the center of it, with the engine at the end of the pillar. The habitat slid nearer or farther from the disk, the gravity of the disk compensating for the force of acceleration so they could achieve (IIRC) a hundred gees or so.

Of course they had a vacuum energy based drive, which neatly got around the question of how you accelerate a collapsed matter disk without rapidly running out of fuel. Which does bring up the interesting point that artificial gravity doesn't normally increase the apparent mass of the vessel; I'd tend to think that it would.

[adam_grif]

Which does bring up the interesting point that artificial gravity doesn't normally increase the apparent mass of the vessel; I'd tend to think that it would.

I feel your pain. Justifying Mass Effect physics is an exercise in futility. Element Zero has two useful properties - lowers the mass in a local region of spacetime when a negative current is applied and increasing the mass when a positive current is applied.

But somehow, it is used to create shields (how it generates repulsive fields is totally unknown and unexplained), artificial gravity (much like you just said, without increasing the apparent mass of the starship), generate remote fields (biotics, the SR1/2's stealth drive can do it too apparently), impart momentum (Biotic push, pull, acts exactly like stock standard psychic powers in cutscenes) and generate stasis fields (Stasis biotic ability, used in cutscenes as well as gameplay).

What really gives you headaches is when the starships are in FTL travel (by reducing mass to near zero, nevermind how that doesn't explain how it's going FTL at all), but simultaneously having the Artifical Gravity being totally uninterrupted and the crew on-board not feeling any effects of the fact that they're effectively massless at all.

And people tell me that ME is "hard SciFi"

[Ted C]

I would presume that any civilization to develop artificial gravity has discovered a working "unified field theory" that allows them to easily convert electromagnetic force into gravitational force by some means.

In practice, the system consumes energy whenever mass moves "up" in the artificial gravity field (increasing the GPE of the object). Presumably some level of inefficiency causes the system to have a minimum constant power draw, even when objects in the field are pretty static.

Incidentally, the fact the system draws energy mostly when mass is being "lifted" through the field means that such a system can theoretically keep the gravity on for quite a while during a main power failure if it has a decent "battery".

[General Zod]

The thing is though, how much energy and resources does it take? In Star Trek at least, the AG system is by far the most stable system they have. Even life support can fail without any apparent failure in the AG. It exists perfectly uniform on every level of the entire ship. They never have to reroute power from auxiliary or other systems to maintain it, nor do they ever attempt to reroute power from whatever the AG system is. Even their Shuttlecrafts have perfectly functioning AG, and they've had it going back at least as far as the NX-01 under Archer.

Seriously, there must have been an absolutely astounding breakthrough in their theories of gravity at some point. They can't even make their doors work right 100% of the time.

Now, to the question, why bother, what's the point? Well, as mentioned, it would be great for maintenance crews. Even if they still need suits, being in an AR environment means that they don't have to worry about tools and such floating away, and they don't have to worry about themselves floating off if they manage to separate their boots from the hull by more than 2 or 3 inches.

They don't have to keep it on all the time, of course, but it just seems like if it's so easy to install in the floors of even a shuttlecraft, it could definitely come in handy.

Like I said though, this is all predicated on the idea that they are generating an attractive force in the floor. The more I think about it, a repulsive force from the ceiling might be more reasonable. Maybe some sort of exotic particle that can transfer momentum fairly well to solid objects (put apparently passes through air without hitting anything). Or I guess they could have figured out the magic of how to easily produce gravitons.

If it takes more energy than simply magnetizing a pair of boots, it's a waste of energy. Incidentally, there's plenty of areas where it wouldn't make any sense to have artificial gravity generators. Why would you need them near the nacelles, or the deflector dish? If enough equipment is between the outer hull and the livable space inside it seems like artifiical gravity would be a waste.

[Eternal_Freedom]

Thinking about it (and I may be wrong here) once the field is on, it may not need very much power: if you're standing on the deck, it's not doing any work on you, and if you jump up, you're supplying the KE that gets turned into GPE, which gets turned back into KE when you start to fall

As for it being ridiculously stabel compared to other ST systems, I remeber a bit from one of the TNg books (#39, Rogue Saucer) where Geordi muses hat everything on a starship is designed so that AG is the very last thing to fail cos humans are generally shit at acting or repairing things in zero-G. That makes quite a bit of sense to me

[General Zod]

Thinking about it (and I may be wrong here) once the field is on, it may not need very much power: if you're standing on the deck, it's not doing any work on you, and if you jump up, you're supplying the KE that gets turned into GPE, which gets turned back into KE when you start to fall

You still need to maintain it, maintaining it requires power. The question is whether or not it uses less power than magnetic boots. Of course a lot of this requires knowing the mechanism behind AG, so without that it's kind of pointless to argue. You could maintain the gravity on the outside of a hull with rotating sections for zero cost, but I don't know about other methods.

As for it being ridiculously stabel compared to other ST systems, I remeber a bit from one of the TNg books (#39, Rogue Saucer) where Geordi muses hat everything on a starship is designed so that AG is the very last thing to fail cos humans are generally shit at acting or repairing things in zero-G. That makes quite a bit of sense to me

The simple explanation is that keeping AG from failing means they don't have to spend money on expensive zero-g FX, the "humans suck at zero-g" explanation really sounds lame. The gravity on the Klingon cruiser in ST6 failed, and there's no reason to assume human ships are that much superior in terms of design.

[Eternal_Freedom]

As I reall, the AG field was deliberately targeted by the BoP, and Klingon ships were bilt as warships so there may not have been the focus on crew-friendliness as there is on Fed ships. I would imagine on a warship they woudl want the guns or the engines to be the last thing, not the Ag fields

It's not that Fed ships were superior in design, just they had different priorities. I recall one book ("Federation" I think) where Kirk comments on the D7 design, saying they put the nacelles where they did because it reduces target profile, even though they knew it would make the warp drive less effecient

And the "humans suck" isn't so lame when you consider the testimony at the trial "I found myself floating, and unable to function"

Plus, with that one, we can't rule out possibly sabotage by Chang or his cronies

[General Zod]

As I reall, the AG field was deliberately targeted by the BoP, and Klingon ships were bilt as warships so there may not have been the focus on crew-friendliness as there is on Fed ships. I would imagine on a warship they woudl want the guns or the engines to be the last thing, not the Ag fields

It's not that Fed ships were superior in design, just they had different priorities. I recall one book ("Federation" I think) where Kirk comments on the D7 design, saying they put the nacelles where they did because it reduces target profile, even though they knew it would make the warp drive less effecient

And the "humans suck" isn't so lame when you consider the testimony at the trial "I found myself floating, and unable to function"

Plus, with that one, we can't rule out possibly sabotage by Chang or his cronies

The books do a lot of stupid shit, so I'm not inclined to take anything they say at face value.

[Eternal_Freedom]

What about the rest of my post?

[Rossum]

What if instead of pulling down on the object then the 'artificial gravity' pushed down instead? Like if there was some kind of kinetic field thing that is based in the ceiling and pushes downward onto whatever is underneith it?

I don't know how such a thing would work, but if the setting has magical repulsers that let hover cars glide several feet over the surface of metal, dirt, water or swamp then that same magical field could probably be used to just push down on people and objects inside a ship.

It wouldn't be possible to contain an atmosphere around the ship with it because the emmiters can only push things away. If anyone went outside they would need magnetized boots to move on the surface of the ship. Actually, if they use the same repulsor technology on the outiside of the ship then it would just push stuff away from the surface, if enemies tried landing smaller ships on the hull then the repulsor emitters would push them away, same with micrometeors or other objects. It could be a sort of defense system like a shield to combat close range weaponry or explosions.


Though... I wonder if the repulsor system would work using sonic technology or if thats even possible. If thats the case then the 'gravity' could only work in an atmosphere and a glitch or malicious programming could change it so that it shatters peoples bones and such.

[Junghalli]

You still need to maintain it, maintaining it requires power.

I don't think that's necessarily a given, as real gravity fields sustain themselves just fine without any constant input of energy. This would actually nicely explain why it always seems to be the last thing to fail: the effect is like real gravity in that it isn't dependent on constant energy input.

In Trek though you're probably right, as apparently borking some mechanism causes an instant return to zero G.

As I reall, the AG field was deliberately targeted by the BoP, and Klingon ships were bilt as warships so there may not have been the focus on crew-friendliness as there is on Fed ships. I would imagine on a warship they woudl want the guns or the engines to be the last thing, not the Ag fields

I'd be inclined to agree with the Klingons then, and think that if your astronauts can't function effectively in zero G there might be something wrong with your training program.

I'd prefer to think that the mechanism is just inherently less failure-prone than stuff like the engines, or just write it up to coincidence and selection bias (we don't see many of the incidents where the AG fails because they'd be hard to shoot ).

[keen320]

If it takes more energy than simply magnetizing a pair of boots, it's a waste of energy. Incidentally, there's plenty of areas where it wouldn't make any sense to have artificial gravity generators. Why would you need them near the nacelles, or the deflector dish? If enough equipment is between the outer hull and the livable space inside it seems like artifiical gravity would be a waste.

There are other reasons for AG besides keeping you on the deck. For one thing, it's much easier to stave off the bone and muscle degeneration that happens to astronauts in zero gravity. For another, it might make your astronauts (or whatever you want to call them) much more comfortable and therefore better able to do their jobs. Basically, convenience. After all, efficiency wise, it's a waste of energy to paint your house. Air conditioning is also a waste of energy, as is using cars instead of mass transit.
I did read one book though, Old Man's war IIRC, where they said only military spacecraft had artificial gravity because of the power draw. The civilian spacecraft only had accel gravity or used a centrifugal torus.

[Junghalli]

There are other reasons for AG besides keeping you on the deck. For one thing, it's much easier to stave off the bone and muscle degeneration that happens to astronauts in zero gravity. For another, it might make your astronauts (or whatever you want to call them) much more comfortable and therefore better able to do their jobs. Basically, convenience. After all, efficiency wise, it's a waste of energy to paint your house. Air conditioning is also a waste of energy, as is using cars instead of mass transit.

I think he was talking about having artificial gravity outside the ship.

Another point on that subject: gravity isn't necessarily desirable. Moving big massive things around is a lot easier in zero gravity.

[Simon_Jester]

I think he was talking about having artificial gravity outside the ship.

Another point on that subject: gravity isn't necessarily desirable. Moving big massive things around is a lot easier in zero gravity.

On the other hand, handling small things is a lot easier with gravity, because things stay where you put them and don't bounce into the air when something strikes the surface they're resting on. Eating and drinking are easier with gravity, because any crumbs or droplets of liquid will gravitate to the surface they rest on rather than becoming a midair hazard.

While handling cargo might be easier in microgravity, the odds are that people in the living spaces of a starship would spend more of their time eating, drinking, and manipulating small objects than they'd spend moving bulky equipment.

[Batman]

Also, moving massive things doesn't get all that much easier in zero g. Lifting them (WRT what would otherwise be the local gravitational 'down') does because you no longer have to overcome gravity, but lateral movement isn't really all that much easier as the blasted thing still masses x tons and still needs y amount of force to move. In fact it may be less convenient as you have to exert the same amount of force to stop the object again. I'd expect to see most of the benefits of zero g (as opposed to the side effects of zero g as present in orbital construction) in moving bulky but low mass items.

[Junghalli]

While handling cargo might be easier in microgravity, the odds are that people in the living spaces of a starship would spend more of their time eating, drinking, and manipulating small objects than they'd spend moving bulky equipment.

Yeah but I was talking about the outside of the ship, where people would probably mostly go to do maintenance work.

Also, moving massive things doesn't get all that much easier in zero g. Lifting them (WRT what would otherwise be the local gravitational 'down') does because you no longer have to overcome gravity, but lateral movement isn't really all that much easier as the blasted thing still masses x tons and still needs y amount of force to move.

Yeah, that's true.

Another point is that in zero gravity it's possible to have structures that would break under gravity. External artificial gravity might not be desirable because it would snap delicate external structures.

[Uraniun235]

From a design standpoint it would be a waste of energy and resources to gravitize the outside of the ship. How often do you need to go out there anyway?

...Very frequently? There's a lot of stuff out there that needs to be maintained and monitored. It's like asking "how often would the crew of an oceangoing ship need to go on deck anyway?"

The outside of the hull is the 'operational surface' of the ship. It's going to be packed with useful devices, and having them go wrong will compromise the ship's usefulness.

Fun trivia, this is the reason why Matt Jefferies designed the Starship Enterprise to have a smooth hull - the idea was to minimize the amount of exposed hardware mounted outside the outer hull, such that the crew could inspect and work on various components (like the phasers or the sensors or what have you) without having to be exposed outside the ship.

[Simon_Jester]

That strikes me as poor reasoning on Jefferies's part. Among other things, it means that the surface directly below the skin of the ship becomes very cluttered. It means you cannot put an armor belt directly under the skin, because there's too many externals in the way. You can have an armor belt, but it has to go inside the pressure hull, which adds a certain amount of redundancy to the design.

Ultimately, it's not healthy operating on a starship if you don't have vacuum gear and the training to use it for the crew. If you do, there's no reason to keep certain components in atmosphere; if anything, gravity is far more useful than atmosphere for working purposes.

[General Zod]

I don't think that's necessarily a given, as real gravity fields sustain themselves just fine without any constant input of energy. This would actually nicely explain why it always seems to be the last thing to fail: the effect is like real gravity in that it isn't dependent on constant energy input.

. . . which is why I specified in the very next sentence that it depends entirely on the mechanism, which is unknown.

[Junghalli]

. . . which is why I specified in the very next sentence that it depends entirely on the mechanism, which is unknown.

Sorry, should have read more thoroughly.

[Zaune]

Regarding Klingon AG tech, I believe it's also at least semi-canon that being a proud warrior race, homegrown Klingon technology not directly involved in blowing stuff up tends to lag behind the rest of the Alpha Quadrant.

[Uraniun235]

That strikes me as poor reasoning on Jefferies's part. Among other things, it means that the surface directly below the skin of the ship becomes very cluttered. It means you cannot put an armor belt directly under the skin, because there's too many externals in the way. You can have an armor belt, but it has to go inside the pressure hull, which adds a certain amount of redundancy to the design.

Ultimately, it's not healthy operating on a starship if you don't have vacuum gear and the training to use it for the crew. If you do, there's no reason to keep certain components in atmosphere; if anything, gravity is far more useful than atmosphere for working purposes.

Why would it be "very" cluttered? Can you produce any documentation on the density of instrumentation and equipment on the Enterprise exterior?

I don't know about "no reason" - working underneath the protection of the ship's skin from cosmic rays, micrometeorites, and vacuum strikes me as safer, easier, and much more comfortable. (It really sucks to have an itch on your nose in a spacesuit.) And depending on the nature and location of the equipment, a lot of it might be accessible from gravity-enabled sections.

If I remember right, the DD(X) program for the US Navy appeared to move towards a similar approach of locating equipment underneath the superstructure - but I've heard DD(X) has some very significant issues, so this isn't me saying "hey it's a good idea" so much as it is "hey, actual high-paid naval contractors seemed to think it could be done, so maybe it's not such a bad idea for an overworked art director to have ".

[Stofsk]

Isn't a lot/most of a submarine's equipment contained inside the hull? That may even be a better analogy, because a submarine that's dived below the waves is in the middle of a hostile environment that is sort of similar to a hypothetical spaceship being in space.

[Freefall]

If it takes more energy than simply magnetizing a pair of boots, it's a waste of energy. Incidentally, there's plenty of areas where it wouldn't make any sense to have artificial gravity generators. Why would you need them near the nacelles, or the deflector dish? If enough equipment is between the outer hull and the livable space inside it seems like artifiical gravity would be a waste.

I think that's oversimplifying things a bit. It takes more energy to run a heater than to put on a coat, but people still run their heaters, even when it's not cold enough to really risk getting hypothermia or getting sick. And again, I'm not saying they should have it running constantly, but that it would be there so that they could activate it if they ever did need to go out on the hull. I think maintenance crews would rather like the idea of being able to put their tools down without having to worry about them floating away.

And yes, like I've said, this is predicated on the idea that their AG system is, by all appearances, a nearly trivial technology to install. If they can afford to put perfectly functional AG systems in every shuttlecraft they build, then it doesn't seem like it can be that much of a problem. I also said this was assuming it was generated by the floor instead of the ceiling.

Anyway, this was really just one example too. The main idea is that for such an apparently cheap and foolproof system, you'd think they could come up with far more interesting things to do with it than just allow people to walk down corridors normally.

Hm, anybody know how the tractor beam is supposed to work? Maybe it's a derivative of the same technology.

[Connor MacLeod]

I suspect alot of the so called "artificial gravity" isn't real gravity in the same way whenever you hear sci fi mention a "singularity" or "black hole" it is not how we traditionally think it is. RAther, we have a magic forcefield that can simulate gravity sufficiently well for puproses of the universe - the nature of the force or the properites we may not know, but it works.

This of course makes it completely arbitrary as far as things like "how do they generate it" and "does it require a energy input/constant energy input." Which pretty much makes it like alot of sci fi tech - We don't KNOW in depth how it works (The way in real life we know how alot of our own tech works in detail - or at least someone does and the capacity ot learn) because that level of info doenst exist. We can only speculate, and we only need to really form a complex theory about it when there is an apparent violation of science (EG momentum or energy.)