Not babies, but youth - ages 5-12 or so.
And while not a wheelchair, per se, it's comparable to a cross between a wheelchair and a motorcycle...
intresting uses of grav tech?
- Thread starter Xerxeskingofking
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Not babies, but youth - ages 5-12 or so.
And while not a wheelchair, per se, it's comparable to a cross between a wheelchair and a motorcycle...
I always assumed it was a grav baby carriage, but you may be right...
If so, seccurity is even more important, as childs of this age move even more than babies.
And, BTW, it has no grav plates nor intertial compensators. the only life support it has is basic environment (heat, lights, etc...), as a current car would have.
There was a grav trailer in one of the T4 books, if I remember right. Hooked to the back of the air/raft. I'm not sure you could sling something, and I don't remember ever reading about it.
I know there's one in an MGT book.
Vladika
SOC-14 1K
I still question using a sling load with antigrav. Seems it would be like picking yourself up by your own bootstraps IF there is a thrust/counter trust situation. Any thrust (inverse gravity) would project downward onto the very load being attempted to lift. Now if it negates gravity, that's another animal altogether, but then negation would just be a zero sum; no lift.
That depends entirely upon what it uses to thrust against, Vladika.
If it grabs the fabric of spacetime and pushes against that, then a load slung isn't being pushed against.
If it generates thrust only at the thruster-plate and the most dominant gravity source (as some have postulated over the years, and supported by the mechanics in TNE and T4 for "drop-off" of effect), then again, the slung load is meaningless - it's own gravity well is too faint to matter.
If it generates a direct downforce below it at, say, 45°, a small enough slung load would be an issue but not an impossible one.
Working an example...
MT Air/Raft, open topped
Mass, loaded 7.2 TmMass, unloaded 1.6 Tm8 Tons thrust (Tt)
assuming a trio of plates of about 2 square meters each...
at 0m, that's 1.333 Tt/m2 or about 13330 N/m2, or about 1.9 PSI.
We'll put the plates even on the bottom, and 0.25m from the ends for the fore and aft. That puts (on the 3m long) 0.25-1.25, 1.0-2.0, and 2.25-2.75m, all at CL±1 on the beam of ±1.5. (this looks to be good enough for matching the illo for now.)
Slinging 500kg of wood, at SG1, in a cylinder 0.6m diameter (a 2' diameter tree), we get a 1.75m length.
Slung horizontally, 1.75x0.6m=1.05m2 if it's slung flat underneath.
At 1m below, Assuming it's center slung, it's fully in the field of all three... and sucking up 1.05m2 of the total 3x4m of downforce each... or about 0.0875*2.666 Tt * 3plates = 0.7T. The effective mass for stress is
0.5T+0.7T= 1.2T on the cables, and only 7.3T lift.
Now, we rig it at 2m. It's still only 1.05m2, but each plate's hitting 5x6m, or 30m2... it absorbs only 0.035 * 8 = 0.28T, puts a cable load of 0.78T, and leaves 7.62 Tt... That slung load is easily lifted. (Oh, and it's pushing 0.36 PSI - mildly uncomfortable.)
At 3m below, it's now hiding within an area per plate of 7x8=56m2... 0.15Tt transferred to the load. It can now be rigged under even a "loaded" Air/Raft - because it's 0.65T cable load, and 7.85Tt still available.
MT Air/Raft, open topped
Mass, loaded 7.2 TmMass, unloaded 1.6 Tm8 Tons thrust (Tt)
assuming a trio of plates of about 2 square meters each...
at 0m, that's 1.333 Tt/m2 or about 13330 N/m2, or about 1.9 PSI.
We'll put the plates even on the bottom, and 0.25m from the ends for the fore and aft. That puts (on the 3m long) 0.25-1.25, 1.0-2.0, and 2.25-2.75m, all at CL±1 on the beam of ±1.5. (this looks to be good enough for matching the illo for now.)
Slinging 500kg of wood, at SG1, in a cylinder 0.6m diameter (a 2' diameter tree), we get a 1.75m length.
Slung horizontally, 1.75x0.6m=1.05m2 if it's slung flat underneath.
At 1m below, Assuming it's center slung, it's fully in the field of all three... and sucking up 1.05m2 of the total 3x4m of downforce each... or about 0.0875*2.666 Tt * 3plates = 0.7T. The effective mass for stress is
0.5T+0.7T= 1.2T on the cables, and only 7.3T lift.
Now, we rig it at 2m. It's still only 1.05m2, but each plate's hitting 5x6m, or 30m2... it absorbs only 0.035 * 8 = 0.28T, puts a cable load of 0.78T, and leaves 7.62 Tt... That slung load is easily lifted. (Oh, and it's pushing 0.36 PSI - mildly uncomfortable.)
At 3m below, it's now hiding within an area per plate of 7x8=56m2... 0.15Tt transferred to the load. It can now be rigged under even a "loaded" Air/Raft - because it's 0.65T cable load, and 7.85Tt still available.
Note that the math for helicopters works very similarly.
So, even if it has to be a beam "pushing" down, it can be done.
Now, assume that tree is 3x as long, and has 2 buddies. 4.5T of tree, and bound into a triangle, about 2x3x1.05=6.3m2. Yes, 5m trees. Too big to fit inside, now. At 3m, it's costing 0.9Tt, loading 5.4T on the cables, and leaving 7.1Tt - you can carry a full load of fuel, 4 guys, and some smaller trees in the bed, and still fly with this trio slung 3m beneath.
So, even then, it's logically slingable.
MT Referee's Manual: "The second major breakthrough is artificial gravity. Created by manipulating subatomic forces, artificial gravity is not antigravity but is instead a unique force that acts upon the natural gravity field created by all matter. Artificial gravity can be made to either push or pull."
In the case of a grav plate, the force is acting on "the natural gravity field created by" small masses to create the effect of gravity. In my example, a 10 liter plate drew 50 kilowatts to affect the contents of a volume of 1 cubic meter - in that instance a region 2 meters tall by 70 cm on a side. A little odd, one wonders why it doesn't just affect everything straight up from it or straight down or whatever, but that's the way the rules set it up: by volume.
Maybe the effect curves off faster than normal gravity. Maybe the effect can only be generated to a certain range from the plate and then the artificial graviton flips into some innocuous other particle. I don't know enough physics to even speculate properly, but the design rules clearly don't let you slap grav plates on the bottom floor and have them affect the ship 10 floors up; there's something about them that limits their effect.
In the case of the grav propulsion unit, a 20 liter unit (twice the size) drew 100 kilowatts (twice the power) to provide a ton of thrust. Unlike the grav plate, that ton of thrust doesn't care how close to the planet you are, as long as you're within 10 diameters; it's acting on the planet's gravity field.
I propose that as long as the mass below the craft is more than 2-3 meters away from the propulsion unit, the propulsion unit will have little or no effect on the mass (unless the mass is something like a planet with an extensive field to act upon). If the mass is inside 2 meters, the propulsion unit will treat the mass as if it were a reversed grav plate - i.e. the mass will be shoved away from the grav unit at 1G, at least until it's 2 to 3 meters away. So, if you're standing there and the grav flyer goes just over your head, you suddenly weigh twice as much, but if it's flying 5 meters up, it has no significant effect on you. And, if you're a 100 kilo mass in a sling a meter below the craft, the mass now "weighs" 200 kilos (assuming a 1G planetary field).
Just as an interesting aside, back in the 1990's (when MT was finishing its publishing run), one of the hypothetical models of gravity in 10-dimensional Super-String Theory suggested the following concerning the "10-graviton":
The graviton (in the 10-dimensional space-time model) was theorized to give rise to 3 particle fields:
1) The Graviton-interaction (spin-2 particle*) - This is the gravity interaction we are all familiar with: always attractive and operating to infinite range in an inverse-square relationship. The graviton is a massless spin-2 particle;
2) The Gravivector (or Graviphoton) Interaction (spin-1 particle*) - The gravivector has rest mass (and hence decays statistically over a short period of time) and gives rise to repulsive interactions between positive masses (we can call it a "Leviton"
)- the field is NOT inverse-square, but is rather statistical and short-range, based on the velocity-distribution of the particles and their decay-rate;
3) The Graviscalar (or Radion) Interaction (spin-0 particle*) - The graviscalar also has rest mass (and hence decays statistically over a short period of time) and gives rise to attractive interactions - again, the field is NOT inverse-square, but is rather statistical and short-range, based on the velocity-distribution of the particles and their decay-rate.
* - NOTE: The Particle-Spin of force-mediating bosons determines the nature of the force: Even-spin bosons give rise to forces that are always attractive; Odd-spin bosons give rise to forces that are repulsive to "like" charges and attractive to "unlike" charges (like photons mediating the electromagnetic interaction - photons are spin-1 bosons).
Spin-0 Bosons are "Scalar Bosons" (a Rank-0 Tensor), Spin-1 Bosons are "Vector Bosons" (a Rank-1 Tensor), Spin-2 or higher Bosons are "Tensor Bosons" (Rank-2 or higher Tensors).
2) The Gravivector (or Graviphoton) Interaction (spin-1 particle*) - The gravivector has rest mass (and hence decays statistically over a short period of time) and gives rise to repulsive interactions between positive masses (we can call it a "Leviton"
)- the field is NOT inverse-square, but is rather statistical and short-range, based on the velocity-distribution of the particles and their decay-rate; 3) The Graviscalar (or Radion) Interaction (spin-0 particle*) - The graviscalar also has rest mass (and hence decays statistically over a short period of time) and gives rise to attractive interactions - again, the field is NOT inverse-square, but is rather statistical and short-range, based on the velocity-distribution of the particles and their decay-rate.
* - NOTE: The Particle-Spin of force-mediating bosons determines the nature of the force: Even-spin bosons give rise to forces that are always attractive; Odd-spin bosons give rise to forces that are repulsive to "like" charges and attractive to "unlike" charges (like photons mediating the electromagnetic interaction - photons are spin-1 bosons).
Spin-0 Bosons are "Scalar Bosons" (a Rank-0 Tensor), Spin-1 Bosons are "Vector Bosons" (a Rank-1 Tensor), Spin-2 or higher Bosons are "Tensor Bosons" (Rank-2 or higher Tensors).
Normally, the Gravivector and Graviscalar interactions cancel each other out and are not observed (or, so the model goes, at any rate . . .
).
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At least in Earth's, if you have naked eye visibility of more than one asteroid as anything more than a dot, you're in the absolutely densest areas. Or so I've read repeatedly. It's just not dense enough to matter.
CosmicGamer
SOC-14 1K
Don't know what the Dune shield is like. Too old. Poor memory. Is it gravitics or repulser tech?
Mongoose CSC: Buckler, Gravitic. A successfully parried weapon is caught by the gravity generator in the buckler.
Mongoose CSC: Shield, Repulsor.
Dune shields? You mean those things that blew up when you hit them with a laser - and somehow triggered a feedback reaction that caused the laser weapon to blow up?
Actually, I suspect it's because Traveller copi - ummm, emulates Jerry Pournelle's vision of the universe. Or at least, that's the way it looks to me. Pournelle's universe had shields: they absorbed energy and changed color as they radiated it off, but they could kill the ship if you overloaded them. You just had to be at least ship-sized to have them. And, Traveller has shields: they absorb energy and bleed it into storage capacitors, but they could kill the ship if you overloaded them. And, you have to be at least ship-sized to have them.
(Although, the Moties were doing some interesting things.)
Pournelle's universe is one where the risks and tactics of personal combat would be familiar to any modern vet, despite the story being set in a star-spanning far future empire. There's very little technology that might hide unexpected ramifications for the personal combat actions he likes to write about - until you run into Moties, and then I sense the mind of Niven in the mix. Traveller similarly provides little personal combat technology that would be difficult for a modern gamer to wrap his head around tactically - and where it occurs, it's usually in the hands of some very advanced alien and/or serves some specific plot need.
I might also point out that personal shields are fraught with all manner of hidden ramifications and may therefore be best suited to a game where all tech is magic tech, eliminating the need for rationalizations. For example,
- how the tech manages to stop a speeding bullet from any quarter without suffocating the man inside, preventing him from firing his own gun outward, or preventing him from keeping his feet on the ground or otherwise interacting constructively with the external world;
- what source of man-portable power could power a shield that can absorb or deflect kinetic attacks from any quarter for a useful length of time, and why that very compact source of power is not being applied to other interesting projects.
There are also the game play consideration: how to run an exciting game in a setting in which your players effectively cannot be harmed by poorly armed thugs, the local fauna, moving vehicles or a host of other potential dangers short of something capable of bodily accelerating the player suddenly enough to cause internal damage.
I think game play is the most important reason Traveller doesn't have personal shields. How do you make a game mechanic that reflects "the faster it hits the harder it stops"? and yes there are ways but how do you do it consistently across the wide range of Traveller weapons like slug throwers, lasers, high energy weapons and environmental hazards like falling off a cliff.
I can think of a whole lot of questions and things that would be needed to be taken into account to use Traveller grav technology for personal shields.
epicenter00
SOC-13
To be frank, anti-gravity and artificial gravity technology are so useful, I'd guess we cannot imagine how much it'd revolutionize society. I think that it is the technological singularity that people bandy about these days; a society permeated by gravity control might very well be unrecognizable to us after a few generations. It'd find its way into everything, including lots of uses we'd never even imagine now. Like perhaps timepieces might use tiny gravitic pulses or something because it is a more precise way to maintain timing or some similar use that'd be very obvious to the people of such a world, but to us, we'd be scratching our heads going, "Exactly how does that work?"
Most of my suggestions are probably hopelessly "Flintstones" (eg; "with anti-gravity to lighten pterosaurs, think of how much further they could fly, Fred!") but:
* Microgravity manipulation: Particularly in surgery I think this would be very useful, especially with artificial gravity; you could keep incisions open and so on without actually physically touching the patient. You could set up anti-gravity to keep blood and other fluids from pooling, then set up microgravity areas to ensure the fluids drain in the directions you want them to. This kind of technology would probably have all kinds of applications in things like distillation and sifting of matter.
* Implanted microgravity devices might allow people to be taller and reduce fatigue, back problems, and similar issues with the basic design of the human body.
* FTL Communications: From the properties of gravity as we understand it, you could probably make a limited range FTL communicator out of them. Since gravity fields are "on" or "off" and don't take time to reach their maximal distance, you could (in theory) use a focused gravity "beam" at something and send data like binary code if the other end has a sufficiently sensitive gravity measuring device. It might not reach light years or replace X-boats, but for just blathering inside of a solar system, such a "grav comm" might be routine.
* Deflector fields. This one is one of those things we sort of ignore in TNE games when they let the "gravitic focusing" genie out of the bottle to explain why Traveller lasers can shoot so stupidly far. If they have grav tech powerful enough to focus lasers to give them stupid range ... couldn't the target ship have grav generators that would bend the lasers away from the ship? For that matter, couldn't it be used to deflect incoming projectiles?
* Mass collapser weaponry: We know that the Imperium has the technology to make partially collapsed matter for armor, presumably by use of gravitics. Couldn't you use such powerful gravitics as a weapon? Some powerful capacitor attached to a powerful gravity plate. It only needs to last long enough to crush missiles like aluminum cans or puree the brains of the crew in a vehicle - the vehicle itself might survive.
Andre Norton mentions ship shields in Star Rangers. They could be overloaded by another ship and destroy the attacking ship if they were too close.
I don't remember any details mentioned on how they worked in the author's universe. From the limited use I saw in her books, they seemed more of a plot device than 'standard tech'.
I don't remember any details mentioned on how they worked in the author's universe. From the limited use I saw in her books, they seemed more of a plot device than 'standard tech'.
CosmicGamer
SOC-14 1K
You might actually like the simplistic gravitic buckler in the mongoose CSC. It is mostly only for melee attacks. The attack is resolves as normal. If a parry of the opponents weapon with the buckler is successful, the weapon is "caught" by bucklers gravitics. The shield doesn't use a lot of power because it is not active all the time. Striking it turns the gravitics on.
The opponent needs to make a strength test to pull the weapon away from the shield. (implying the gravitics are not overly high power) While recovering ones weapon may not be too difficult, it is the persons action for the round. Someone could opt to just let go of the "caught" weapon and do something else. Maybe pull a backup weapon or choosing to fight unarmed.
Perhaps those who like a more realistic science like equal and opposite reaction could use opposing strength checks for the possible tug of war if the weapon does not break free of the shields gravitics.
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Actually, that works pretty well with the idea of artificial gravs having very limited range. As the lower "pull" field weakens, the upper "push" field strengthens, providing a more uniform field effect. Probably wouldn't be exactly uniform, but maybe good enough that no one but an engineer would notice.
My favorite flavor of AG is from Alan Dean Foster's Flinx of the Commonwealth series... You generate an artificial gravity well in front of the ship, which then pulls the ship in. But note that the inverse square law still applies...
So, if the ship is 5 units long, and the well is 2 units ahead... and has strength 100 at 1 unit...
Pull at distance
1 = 100
2 = 25
3 = 11 (near end)
4 = 6.25
5 = 4 (center of ship)
6 = 2.77
7 = 2.04 (far end)
At the far end, the ship is falling faster than they are, so they "feel" pulled away from the gravity well, while, at the near end, they're falling faster than the ship.
I can't remember the rules for tidal force - do you average the pulls on the ship over distance to find the center of pull, or do you simply use the pull at center of mass?
(Now, there are a lot of people who say the math can't work on it, and others who say it can, and I don't care, either way. It's a fun and consistent drive that requires that the act of generating the gravity well not push the ship back, and that the rebound last long enough to let the ship fall before generating the next one.)
So, if the ship is 5 units long, and the well is 2 units ahead... and has strength 100 at 1 unit...
Pull at distance
1 = 100
2 = 25
3 = 11 (near end)
4 = 6.25
5 = 4 (center of ship)
6 = 2.77
7 = 2.04 (far end)
At the far end, the ship is falling faster than they are, so they "feel" pulled away from the gravity well, while, at the near end, they're falling faster than the ship.
I can't remember the rules for tidal force - do you average the pulls on the ship over distance to find the center of pull, or do you simply use the pull at center of mass?
(Now, there are a lot of people who say the math can't work on it, and others who say it can, and I don't care, either way. It's a fun and consistent drive that requires that the act of generating the gravity well not push the ship back, and that the rebound last long enough to let the ship fall before generating the next one.)
