Artificial Gravity in TREK

Discussion in 'Trek Tech' started by Wingsley, Dec 27, 2015.

  1. Wingsley

    Wingsley Commodore Commodore

    Joined:
    Feb 18, 2007
    Location:
    Wingsley
    This thread is focused on how artificial gravity works in the STAR TREK Universe, most generally on Federation starships, but also on all other spacecraft including orbital and deep space stations, etc. I am specifically concerned about how it works in TOS, but we can talk about all of the TV series as well.

    One constant notable feature in STAR TREK, right from TOS forward, is that manned spacecraft invariably employ artificial gravitation technology of some sort for the benefit of the crew. This seems to allow the astronauts (of all species) to live in an environment that simulates/emulates natural life on a planet.

    (1: All Federation starships and shuttlecraft shown in TOS seem to employ artificial gravity to simulate something that must be Earth-normal 1g, at least by appearances.

    (2: Even damaged or otherwise disabled spacecraft seem to ultilize 1g-like gravitation of some sort, as even the adrift Botany Bay and Constellation, as well as the lifeless Exeter and Defiant, still seem to have working gravity.

    (3: Passage from one human-habitable space vessel to another doesn't seem to be a big deal for astronauts, so we can assume that even when Kirk caused the Astral Queen to dump the theater acting company and let the Enterprise take them aboard, the Players simply expected not to have to contend with any nasty environmental surprises. Ergo: the environmental conditions (gravity included) must be standardized.

    My question is this:

    If space-suited astronauts on the outer hull of a space vessel require "gravity boots" in order to walk about and not drift off into space, and yet non-suited personnel inside that hull generally take their pressurized, 1g internal environment almost for granted, how is this gravity produced with such reliability and fidelity? It wasn't until ENT's "In a Mirror, Darkly" that we see someone doing something unusual (not 1g) with the ship's environment. So, in-Universe, how is this supposedly done with no visible signs outside the ship? (Enterprise sat at the Romulan Neutral Zone in "Balance of Terror" with her power down, and yet her crew enjoyed seemingly Earth-normal conditions, only dimmed lights and non-functioning peripherals, and the only thing to alert the intruder-vessel was Spock's accidental signal.)

    So how is it (supposedly) done? I do not understand.
     
  2. DonIago

    DonIago Vice Admiral Admiral

    Joined:
    Mar 22, 2001
    Location:
    Burlington, VT, USA
    We had artificial gravity failures in TUC and an episode of VOY (a portion of the ship, not the whole ship), FWIW.

    I think the tech manuals suggested that the artificial gravity system works in such a manner that even when power to it fails it will continue to generate a gravity field for at least a few hours.

    I kind of thought the gravity plating was in the deck floors, but I may be misremembering that aspect. In any case, that would be why gravity boots are still needed outside the ship. Though I'd think the'd be a reasonable precaution in any case, especially as body protection is going to be needed regardless.
     
  3. Go-Captain

    Go-Captain Captain Captain

    Joined:
    May 23, 2015
    In TNG: "Genesis" I believe Picard or Riker says not to worry, and that the ship will have 45 minutes of gravity without power.

    In VOY: "Learning Curve" Tuvok increases deck gravity for a jog through the corridors, in order to make it more strenuous. However, it was slight enough the person did not believe himself, since the person who states it becomes more irritated when Tuvok states he is correct.

    It is unfortunate ENT is the first time we ever see deck gravity used offensively/defensively. It is a very obvious trick. Even if you are trying to protect your enemy the Voyager example shows us control is precise enough to merely wear an enemy out faster than your own personnel.

    The form of gravity shows us it must not work as natural gravity. For one thing, starships don't act like moons when they get near planets, causing dangerous tidal forces. That's in addition to needing magnetic space boots. So gravity definitely doesn't escape the hull.

    Secondly, gravity decreases with the square of distance, and if the deck plates are a light pseudo mass acting at extremely short distance, then the gravity field would fall off rapidly. A person's head might be in zero g while only the soles of their shoes experience 1 g, making it extremely dangerous and difficult to get used to walking. Gravity like that would be better implemented from a single point in a tower arrangement, so the gradient can be spread and kept less abrupt in the vertical. Yet, Trek gravity seems as if it is consistent in the vertical, even when transitioning decks. We are left with gravity without a gradient, with an arbitrary cutoff distance; it's gravity closer to a laser than a light bulb.

    Third, we have inertial compensators which act on people to counter Newtonian acceleration. They act uniformly across the entire ship, cancelling out lateral, and linear acceleration. That means they are applying opposite equal force, and it cannot be applied to only the surface of people, since their guts and brains are not crushed against their skin, and they don't get fully body bruises when accelerating super hard. Instead the field somehow permeates everyone and everything fully the water of a full sink permeating a sponge. This feat seems to be the real source of deck gravity on ships, as it works in every direction and cannot be gravity, allowing it to have non-gravity properties. My official guess is subspace is how it is done, as in space magic.
     
  4. Timo

    Timo Fleet Admiral Admiral

    Joined:
    Aug 26, 2003
    Unless you count TAS "The Practical Joker".

    ...But probably wouldn't suffice for keeping people attached to the floor, except if they specifically shuffled their shoes along the carpeting without ever lifting a leg. Another factor ruling out this as the true nature of Trek deck gravity is that an object dropped by a character falls on the floor as if in California...

    It would be simple to argue that what passes for gravity aboard Trek starships does not follow the inverse square relation. There's no explicit reason why it would have to, after all - and we see gravity behave very differently when (supposedly) employed in tractor or deflector beams or shields.

    OTOH, if we ignore the possible gravitic aspect of those devices, for all we know, Trek deck gravity is homogeneous and only ever erected between two parallel plates, one in the floor and the other in the ceiling - analogous to an electric field, say.

    ...Which might be why "life support" is such an energy hog that diverting from it allows even the warp drive to run better.

    Although whether the mechanism deals with each and every piece of mass within the starship separately, reaching into our body cavities to do it work, or simply cordons off a volume of space where acceleration is not felt because no acceleration takes place within that frame of reference, is an interesting issue, be it semantics or then fundamental (pseudo)physics.

    Timo Saloniemi
     
  5. Mytran

    Mytran Rear Admiral Rear Admiral

    Joined:
    Aug 5, 2009
    Location:
    North Wales
    This might have the advantage of "recycling" a lot of the gravitons would otherwise be wasted on unoccupied parts of a ship.

    FWIW, I imagine that the Inertial Dampeners are just an extension of the gravitational field generated by the ship itself. After all, gravity and antigravity fullfill the ID's function of "pull" and "push" back quite neatly, depending on the requirements of the circumstances. Even the smallest Star Trek shuttlepods have got gravity well and truly tamed, so utilising it for other purposes like this should be trivial.
     
  6. Wingsley

    Wingsley Commodore Commodore

    Joined:
    Feb 18, 2007
    Location:
    Wingsley
    One reason for pretty much all spacecraft seen in TREK consistently using on-board interior artificial gravity, as touched on in this thread thus far, is that it creates a controlled interior environment that protects all personnel, equipment, supplies and cargo from external gravitational/acceleration complications while the craft is in flight. It is therefore a forgone conclusion that even NX-Alpha and Cochrane's own Phoenix used some kind of artificial gravity to afford the pilots a level of safety and comfort, even if the ship is pulling many g's.
     
  7. ancient

    ancient Vice Admiral Admiral

    Joined:
    Aug 5, 2005
    Location:
    United States
    Yeah, inertial dampeners are essential to the survival of the crew given how manuverable Trek ships are, I imagine the grav system is just an extension of that system. It's probably made up of millions of micro generators on a plate that hold their "charge" even when they aren't being powered for a while.

    I can imagine the grav system shoots out gravity particles from a plate on the floor, and another plate on the ceiling absorbs any unused ones & recycles them. Or something.
     
  8. Timo

    Timo Fleet Admiral Admiral

    Joined:
    Aug 26, 2003
    One might also argue that the super-duper sublight propulsion in the early 21st century is based on inertia manipulation already, and that onboard gravity is a mundane spinoff technology. And that the hull polarizing trick of the 22nd century is a somewhat more demanding spinoff, with gravity set on very high negative...

    Timo Saloniemi
     
  9. Paul Weaver

    Paul Weaver Rear Admiral Premium Member

    Joined:
    Apr 12, 1999
    Location:
    Cheshire, UK
    Not really. Phoenix had normal ICBM G-Forces, then went into warp while in orbit. There's no evidence that Warp actually moves the ship (rather than moving the universe). At one point it had accelerated to 20,000kps (1/15th speed of light), but the warp field was clearly on line at this point.

    LAFORGE: Warp field is looking good. Structural integrity is holding.
    RIKER: Speed, twenty thousand kilometres per second.
    (Display shows Warp is "nominal")
    COCHRANE: Sweet Jesus!
    RIKER: Relax, Doctor. I'm sure they're just here to give us a send-off.
    ...
    (Display shows SPACE WARP ENGAGED)
    RIKER: Thirty seconds to warp threshold. ...Approaching light-speed.
    COCHRANE: We're at critical velocity.
    (Standard Warp Flash)

    We can see the warp flash happens at Warp 1, but the ship wasn't being driven by a chemical rocket accelerating to 20,000kps, there's no evidence of Newtonian acceleration beyond normal suborbital flight, thus no requirement for inertial dampeners.

    For artificial gravity, they were strapped in, and there's no indication they weren't in freefall for the flight.
     
  10. Timo

    Timo Fleet Admiral Admiral

    Joined:
    Aug 26, 2003
    Or then quite a bit above, as she seemed to reach Earth escape velocity (with margin) with her lower stage alone, in very little time to boot (thank you, Steppenwolf)...

    It's difficult to say what that business about first gradually accelerating and then going past lightspeed was - the only other time we see that happen is in ST:TMP, so perhaps that's what you do with untested warp engines to, well, test them? Whether warp needs inertia control or not, though, is far from established.

    Timo Saloniemi
     
  11. Paul Weaver

    Paul Weaver Rear Admiral Premium Member

    Joined:
    Apr 12, 1999
    Location:
    Cheshire, UK
    It's not established, but if it does that means the Phoenix needs it, so another thing for Zef to invent. The novel "The Sundered" does suggest that it wasn't just a drunk man in Hicksville Montanna that built the drive, having had lots of previous tests before WWIII kicked off, so it's a possibility.

    I don't see any evidence the Phoenix reached escape velocity before kicking in space warp. We know it reaches a c. 200km height, no evidence it's in orbit let alone escaping. A Titan 2 can put a couple of tons in orbit, so straight up with no sideways motion would be far easier.

    Once up at say 200ks they'll have a couple of minutes to start warping space.

    As for the takeoff, it looks like they cut some time out of the 2 or 3 minute trip and only showed us the highlights.
     
  12. Timo

    Timo Fleet Admiral Admiral

    Joined:
    Aug 26, 2003
    But the thing is, it doesn't even "look" like that - "Magic Carpet Ride" plays for a given number of consecutive seconds, and then is muted in a scene that soon establishes the second stage separation without any cuts.

    Also, this is 200 kilometers?

    http://movies.trekcore.com/gallery/displayimage.php?album=491&pid=52030#top_display_media

    This is 400 km.

    http://www.nasa.gov/sites/default/files/thumbnails/image/space_station_over_earth.jpg

    The Phoenix appears to be significantly higher than that.

    There's another thing to consider: if the upper stage is "a couple of tons", we have our supernaturally good sublight engine established right there. Or did Cochrane wish to risk it all and trust his return to Earth on another warp flight? Conversely, if the upper stage carries a realistic amount of fuel for a return to Earth, it's a supernaturally large payload for a lower stage to lift in the fashion shown.

    So, ultimately,

    is not necessary. It could be old news in the 1990s already. Or at least as of 2018, when a breakthrough in sublight propulsion is explicated and makes interplanetary cryosleep unnecessary and week-long rescue flights to Mars possible.

    Timo Saloniemi
     
  13. Go-Captain

    Go-Captain Captain Captain

    Joined:
    May 23, 2015
    We can also see the Phoenix is moving at an extreme velocity away from Earth when he looks out the window.

    https://youtu.be/DYE3nm9voUk?t=1m58s

    I've mentioned it elsewhere, but Data mentions a radiation leak from the Phoenix which is indicative of antimatter, after the Borg attack. It is theta radiation. Antimatter handily explains why the first stage would be so powerful, and explains how the second stage would have enough power to get back. In either case it does not have to be a pure antimatter reaction, it could just as easily be an antimatter catalyzed fusion reaction.
     
  14. Wingsley

    Wingsley Commodore Commodore

    Joined:
    Feb 18, 2007
    Location:
    Wingsley
    I do not recall anything in STAR TREK: FIRST CONTACT that indicated zero-gravity inside the cabin of the Phoenix after leaving Earth's atmosphere. Anyone who can recall a floating pen or waving hair or anything like that is welcome to point it out, of course.
     
  15. Mytran

    Mytran Rear Admiral Rear Admiral

    Joined:
    Aug 5, 2009
    Location:
    North Wales
    Well, the men all had short hair (like in 2001) so we were never going to see anything like that. However, given the apparent velocity needed to achieve orbit in such a short source of time, some sort of antigravity based Inertial Dampening system would be essential. Otherwise, wouldn't the crew have been flattened into their chairs by the g-forces.

    The ID might not have been needed once the Warp Field started to form, since as discussed elsewhere the ship itself doesn't "move" in the conventional sense.
     
  16. Timo

    Timo Fleet Admiral Admiral

    Joined:
    Aug 26, 2003
    Was there ever a moment when the Phoenix wasn't accelerating? Even if it were fifty gees at times, two gees at others, and an IDF kept it at a convenient level, the net effect seemed to be that everybody was pressed against their seats all the time. I mean, wasn't the cockpit set built so that the forward windows faced up?

    Or then making some sort of a clockwise turn - perhaps again speaking in favor of a superengine that can afford to do radial departure from orbit, rather than the more "natural" tangential-spiral.

    Good point - "theta" is supposed to be futuristic and specifically antimatter-related rather than something a fission- or fusion-powered contraption would leak. Interestingly, the radiation is coming from the "throttle assembly", not the power source... Does this mean this "rocket" works on the principle of a "single bottle" within which antimatter and matter annihilate and then spew the resulting masses and energies out of the throttle thing? As opposed to a system where m/am annihilation produces power in some closed loop, and this power then propels the rocket propellant out of the rocket nozzle through a throttle assembly, without imposing any theta radiation on said propellant or the parts that come to contact with it?

    Timo Saloniemi
     
  17. Paul Weaver

    Paul Weaver Rear Admiral Premium Member

    Joined:
    Apr 12, 1999
    Location:
    Cheshire, UK
    Accelerating until first stage seperation, then in swift time they brought the warp core online. There's then a cut of indeterminite time between bringing the warp core online and the 5 minute countdown to the Vulcan's being in range (p.s. why are the Vulcan's so close to Earth? I guess it's the whole "subspace lanes", as no ship would ever fly through any solar system at any point on a journey from A to B, yet it happens a lot in trek)

    https://youtu.be/nIpXYU-9CBM?t=1m52s

    Difficult to tell what the altitude here is, maybe 10,000km? It does show that https://youtu.be/nIpXYU-9CBM?t=1m33s must be a camera trick though - as there's no way they are that high then, but still see Earth out of the window 20 seconds later.

    I don't see evidence of a turn - or even a change in orientation - I do see evidence of the camera angle changing to bring the Enterprise into shot, however even if the camera wasn't changing angle it would only be a c. 15 degree orientation change, and that's got nothing to do with your actual direction of travel.

    https://youtu.be/nIpXYU-9CBM?t=2m21s

    If you're travelling (or planning to travel) at escape velocity it makes no difference which direction you're travelling anyway, and given the speed that the Phoenix must have been travelling at at this point, the orientation of the ship makes no difference. Escape velocity at Earth's surface is 11.2kps, slightly lower at 3000km (9.2kps) or at 10,000km (7kps)

    First stage was firing for 40 seconds, even at 5G (and given their arm use that seems unlikely) that would only put them 40km up, still well in the atmosphere (.5*9.8*5*40*40 = 39.2km)

    Assuming no time skip between the nacelles engaging and bringing the warp core online, and an altitude of 10,000km at 55 seconds when Zef looks out of the window (they are closer than 1 planet diameter), that would imply a speed of around the 300kps at first stage shutdown at 40s, so 6,000km in the first 40 seconds, and 4,500 in the next 15.

    That gives an acceleration of 7500ms^-2, or 760G.

    If we halve the altitude Zef sees to 5,000km, we can drop the speed to 150kps, and the acceleration to 380G, but it doesn't make any difference. Without an inertial dampening field and/or structural integrity field the ship can't possibly have survived without falling apart - it's still a Titan missle.

    That's assuming constant acceleration, but you'd want to keep speed lower in the lower atmosphere to avoid the heating of that much compressed air going up -- it would make a lunar reentry look like an EZBake oven in comparrison. Even if you keep to an average 5kps for the first 15 seconds (say 40k height), to get you above most of the atmosphere at a reasonable speed, you're bumping up your requried end velocity by 30%.

    So I'll accept that the Phoenix must have had inertial dampeners for the initial launch. Not convinced about artificial gravity though, and in the novelverse, the asteroids that were in orbit didn't have gravity, despite helping Cochrane with his tests.

    "She felt their weight decline to nearly nothing as the lift progressed toward the asteroid colony’s core, the region least affected by the spin that created the nearly Earth-normal gravity experienced by those who worked and lived on the outermost levels"
     
  18. Timo

    Timo Fleet Admiral Admiral

    Joined:
    Aug 26, 2003
    I'll clarify, but not in order to disagree...

    Whenever a view through a window shows the background moving to the left, the two possibilities are linear motion to the right and clockwise rotation. At distances such as involved here, the two are rather difficult to tell apart. OTOH, the last we saw the Phoenix, Earth was directly behind her, not off to port, so some turning after that is already implied.

    Thus,

    But there is, if after the separation Cochrane for some reason turns sideways to prep his ship for the next leg. The first stage nozzle was glowing a lot; the upper stage also has a nozzle, but it doesn't glow right after separation, thus possibly meaning there's no further acceleration there, not until Cochrane is done turning and preparing and engages this thrust system that rattles and accelerates the ship.

    Amusingly, the next time we see the nozzle, it's again dark - but has an excuse for being that, as at that point the warp engines are taking the strain... The absence of scenes of nozzle glow is acceptable in this model.

    Might be Troi is flat out lying to Cochrane about that. ENT later reveals Vulcans have an active interest in Earth and conduct spying missions, or at least did in the 20th century. Troi might be counting on the inexperienced Cochrane not realizing the absurdity of her claim, and she has to paint the Vulcans as good guys the best she can to make Cochrane accept his duty of launching the warp test. Revealing them as spies wouldn't do that.

    Would Cochrane understand the implications of warp drive? The freedom from having to hop from star to immediately neighboring star, the cosmic absurdity of "passing through" B when going from A to C, but also the liberty of making all sorts of detours without losing centuries, or fortunes, or mountains of fuel? These might not yet have occurred to the apolitical inventor.

    The way to restore truth to Troi's words would be to say that Vulcans at that point have abandoned interest in Earth, but retain a keen interest in something else in the Sol system, and for that reason keep passing through it every now and then. It's only in offscreen Trek that there are/were interesting alien civilizations on Mars or Ganymede or whatever, though. But the interesting thing about Sol might be the visitors, who do keep coming even according to onscreen material.

    Cochrane probably had several futuro-aces in his sleeve, as his "rocket" doesn't create much of an effect in surrounding glassware at launch. How to explain that? A drive system not really relying on a rocket exhaust (merely involving a tailpipe that gently puffs out blue flame as a side product of some sort)? An exhaust carefully controlled (by forcefields or gravitics?) not to interact much with the surrounding atmosphere? An old USAF system installed in the silo, an air curtain of some sort that reduces the acoustic impact of the launch for military reason X (say, retention of the nicely camouflaging forest around the silo)?

    Artificial gravity might well be absent from Cochrane's rig on grounds of being too bulky or expensive for the mere test rig. But a model taking into account its presence on a 1996 interplanetary spacecraft, and the subsequent absence on a 2030s Mars vehicle, could and perhaps should cover Cochrane's lack thereof without going the "he built it in a garage with Mad Max after Judgment Day, cut him some slack" route.

    It's too bad we never see non-spacecraft examples of gravity manipulation in (on!) 20th or 21st century Earth. A hovercar, a gravitic amusement park ride or an AG-based chemical separation system would be helpful in establishing at least something about the tech timeline, and about the relative difficulties of the various forms of application.

    Timo Saloniemi
     
  19. Wingsley

    Wingsley Commodore Commodore

    Joined:
    Feb 18, 2007
    Location:
    Wingsley
    Correct me if I'm wrong, but if you compare the launch seen in APOLLO 13 to the launch we see in STAR TREK: FIRST CONTACT, Cochrane, LaForge and Riker seem to have an awfully smooth and stress-free ride when comparing an ICBM to a Saturn V. (I assume that the depiction of Apollo 13's launch, in terms of the what the characters are shown enduring, would be reasonably accurate.)
     
  20. Paul Weaver

    Paul Weaver Rear Admiral Premium Member

    Joined:
    Apr 12, 1999
    Location:
    Cheshire, UK
    Until first stage sepeartion (about t+1m10 on film, 3m in reality) doesn't look too different to me, and at this point they are above the atmosphere.

    That doesn't really help with altitude reckoning, unless the ship had already turned left, and was now turning right. If the ship had taken a standard gravity-turn take off and facing prograde, but was now positioning for a radial burn (for whatever reason), the shot we'd see earlier would have shown the ship in orbit, not already travelling radial.

    If the planet was receeding in the window due to a turn, that's fine, but it implies a far lower change in altitutde speed.


    Are you saying she's hiding something?

    The vibrations caused by the takeoff (again the camera angle shows the ship launching from far closer to the bar than in real life) were perfectly cancelled out by "Magic Carpet Ride", hence needing to abort unless he could find it ;)

    The closest we've seen to civilian life would be Past Tense, which doesn't show anything much more advanced to our own current world in civilian street. However in 2037 Nasa launched a third attempt to explore outside of the solar system, again no sign of artificial gravity or not. In 2032 Ares IV did NOT have artificial gravity though.

    Futures End proved that there was at least one DY-100 style ship known about in the mid-90s, and Star Trek IV shows us that there had been "conclusive advances on toroidal space-time distortion" about 10 years before First Contact. Perhaps the Eugenics wars meant that the ability to create anything as advanced as a DY had been lost by the 2010s (there were cryo ships in the 90s - the botony bay and the Claire Raymond satelite, but spaceflight seemed to regress somewhat if Ares IV was around in the 2030s). Presumably around the time of Ares IV's launch the records from the superior spaceflight technology in the 90s were uncovered by America, allowing Nasa to give rapid deployment of extra-solar ships over the next decade (althoguh the ISA didn't have access to these ships at the time), as well as more ambitious intra-system ships - the first long-distance manned trip (due to the position of the planets for slingshots) would be the Earth-Saturn probe, which would have artificial gravity. The breakthroughs in this second-golden-age of space flight (2030-2050), and the re-emergence of some Eugenics era technologies, would have led to Cochrane's subspace based technologies.