First important thing - The field starts from the field generators and radiates out. As the field generators are underneath (embedded into the back of) the armour, this means that when a projectile hits the armour it is still within the field, and as the field's power increases at an escalating rate as it is penetrated, the projectile would not even have reached the strongest part yet (the field it has so far experienced could even be insignificant). I see this as just an unavoidable fact of the way it works, and not deliberate on the manufacturers part.
If it causes too much trouble, obviously I could alter it.
Jub wrote:What's the KE like on the type of gun that would drop a decently made and tuned shield through sheer brute force and how much less energy does that take than sustained fire from a normal infantry weapon?
I had avoided thinking too much about the actual kE and muzzle velocities, etc, given I lack the knowledge to avoid making a mess of it, but it's something that does have to be done. So I'm going to make some guesses from wikipedia and my arse, and maybe we can make some sense of it.
It seems some reasonable averages for muzzle velocity and bullet weight for modern weapons are:
pistol: 300m/s, 6.6g -> kE 0.3 kJ
Assault rifle: 930m/s, 10g -> kE 4.3 kJ
heavy machine gun: 1000m/s, 40g -> kE 21 kJ
Now, I've described the needle rounds as "hypersonic", but reading wiki on railguns makes me lean towards a needlegun has a muzzle velocity perhaps 3 to 4 times higher then a modern weapon of similar use, with a bullet normally half the mass. Heavy needlers however typically have a even higher muzzle velocity and much lighter bullet then a modern HMG
Needle pistol: 1000m/s, 3g -> kE 1.5 kJ
Needle rifle: 3000m/s, 5g -> kE 22.5 kJ
Heavy Needler : 5000m/s, 10g -> kE 125kJ
If we say armour comes in 3 grades for simplicity (when really it would come in a bewildering array), they would be:
1) Militia/Police - scale vest over the top of plastic plates containing the field generators. Due to the limited armour protection, the field has to be quite untuned, it will protect from pistol fire, but quickly fails against rifles.
2) Infantryman - armour protection similar to today (including inserts); the field can survive 10 to 15 rifle shots over a five-second period, but a heavy needler can sometimes (25% maybe) punch right through with a single shot, and 3 to 5 will cause burn-out (at least localised to the hit areas).
3) Elite heavy armour - This looks like a futuristic suit of gothic plate mail, and incorporates the best and most expensive materials and technology. It would take the combined, lengthy, sustained fire of a squad to bring him down with rifles (and normally this is through power exhaustion), or scores of rounds from a heavy needler (one-hit penetrations are extremely unlikely). These suits are extremely expensive and only practical for specialist work, otherwise tanks are cheaper.
An attack is stopped by a combination of dispersing the energy (this is separate to the conducting the heat, and is akin to the way light is scattered upon hitting a translucent surface), and pumping energy into the surrounding field. The amount that needs to be pumped depends upon how localised the attack is (the more pin-point, the more energy needed, while for attacks such as broad explosions no extra energy is needed). For needle-pointed attacks such as needle guns, assume normally four times more energy is needed to stop the attack as the attack contains. This is affected by tuning, a highly tuned field needs much less energy then a low-tuned one.
At range it seems like you'd have two main options heavy, fast, and slim or tiny, fast and lots close together. Things like metal storm would fit the later and I could see people carrying computer aided multibarrel weapons and trying to unload a tube into people for a potential one hit kill. Going simpler you'd see less full auto and more burst weapons, like those Russian rifles that can put two or three shots down range before recoil kicks in.
This seems reasonable. Although it is in one view an inefficient use of energy as one attack doing 125kJ is more powerful then 10 attacks doing 20kJ, it could be far easier to create the 10 attacks at 20 kJ.
As for chemical attacks, being space-travelling civilisations they are not unfamiliar with totally contained suits. While it would give militia-grade forces serious problems, I see it only being an inconvenience for standard troops, and elites are in totally enclosed suits as a matter of course anyway.
Simon Jester:
Nitpick accepted, although if you want you can come over and do my daughter's hair. She's riven with the damned things right now. However, when I'm visualising it, I see a laser beam and the path of a bullet, so I'm vectoring from that. Yes, I have magic eyes and I can see laser beams without them hitting me right in the eye.
Notice my continual use of the word "contour"? That's because yesterday, for the life of me, I
couldn't remember the fucking word 'gradient'! It's annoying when that happens.
I'm aware of Dune, and I even had a mention of it in my post before I decided it was too wordy as it was and deleted it.
However,
MY fields don't blow up when hit by laser beams!
A Field which seriously damps the velocity of an incoming projectile below about 500 m/s will become increasingly hard for air to get through, which is bad enough. But if it costs energy to make the field damp something, it's even worse, because your Field is permanently left trying to damp out collisions with the air, and acting as a sort of very expensive refrigerator.
I had never considered that. It's true though that for the good armour, much of the lower velocity stuff doesn't have to be blocked, and maybe the militia stuff only protects the torso where the armour is, meaning the field can be more tuned and it also wont stop breathing.
I wonder how it would work as a civilian refrigeration unit?
Could you outline a set of conditions under which the Field might actually 'fail brittle?
A field most usually brittle fails when cold (ie, is not holding any energy within the field), is very untuned (set to stop very low velocity attacks), and is hit by a very powerful concentrated attack. For example, if you were to switch on a field set to stop thrown rocks and then shoot it with a heavy needler, it will very likely brittle-fail, and the fact that if it doesn't it will certainly burn out is besides the point. The difference in this case between brittle-fail and burn out is that brittle-fail simultaneously fries the entire shield, while in the example given it's likely only the local generators would die (as they weren't able to spread the load in time to others), and brittle-fail can even happen when a military-grade field is single-shot with a needle-pistol, but it would never burn out. Theoretically, even a huge star ship's field could brittle-fail from a needle-pistol round; of course, theoretically I could walk towards a door and quantum tunnel through it, if you get my point.
No-one knows why the fields brittle-fail. Force fields utilise an area of physics called by laymen "Sub-quantum physics" (until I can come up with a better name for it), and no-one of the known races, living or dead, understand it. They use it for force fields, they use it for interstellar travel, but they don't pretend to understand it, and it does some weird shit.
I'm satisfied if it takes heavy weaponry to take these guys down quickly. Yes, a cannonball should pass straight through, and then even if it wont penetrate the armour, the concussion should kill or maim, but if people have to carry around personal cannons, that could be inconvenient in house-to-house.
Does it pop like a soap bubble, or do you get an unhelpful result equivalent to drilling a 1-mm hole in a steel plate, which has basically no effect on the plate's strength?
On burn-through, if the field is overall cool it will only be the local generators that fail. If the field is overall red-lining then the shock of the failure will normally cause the others to cascade-fail. So in the case of a single-shot penetration (heavy needler into a militia-man), it will cause a hole in the field, but the surrounding field will be relatively fine (some damage may have been done to surrounding generators causing loss of performance).
Your real problem is bringing back melee weapons in an environment where material science is so good. I know I couldn't swing a battleaxe hard enough to put it through the kind of armor you're describing...
Humans, yes. Humans massively prefer guns. There is another race called the Tai'Qu who are about 50x the strength of a human, and who are really good at and enjoy hand-to-hand combat. At that strength, the sheer concussion of their blows (if the weapon doesn't penetrate) count as lethal attacks even against themselves. In response to the Tai'Qu, human weapon manufacturers are trying to come up with powered melee weapons (drills, power-claws, etc). They're still working on it.
By the way, Zarrin in the story above is Tai'Qu. They have nothing
against guns, as such, and they'll use what gets the job done.
madd0ct0r
incendiary bullets or bigger flare-slugs could be a way to force hot overloads, particularly with your initial description, since they'd fall slower in the field too. Petrol bombs would look very pretty.
and hey! if you get a glancing hit the side of the projectile in the field slows down, reorintating the bullet towards the person! = Homing bullets!
I hadn't considered the effect of fire weapons. At the moment, I have nothing.
You know, it
would cause the projectile to curl in! Assuming competent armour, I don't see it having much effect, but amusing none the less.
lPeregrine
Two more things that would probably be considered as counters:
1) Exploit conservation of momentum and just hit the field hard enough to rip the generators out of the armor. Obviously this at least shuts down the field, and potentially rips them out of the armor and through the person wearing it (a hit from the back would send the back-mounted generators straight into your vital organs). And of course with larger weapons the blunt-force impact becomes a big problem even if the structure survives. You could have a grenade that aims for maximum blast wave to stun the person and knock them down, and then stab them to death while they're helpless.
2) Two-stage rounds designed to cause a local failure and then slip the second shot through the gap. If you want to avoid this you'd have to make sure that the size of a local failure is smaller than the accuracy of the second shot, so getting a hit through the shield requires too much luck to make the idea practical.
Of course for large-scale battlefield use chemical weapons would be common (at least in the absence of political factors) since the field won't do anything to stop a slowly drifting cloud of poisonous or corrosive gas. But since you're not trying to make them immune to guns at long range that's probably not too much of a problem, in a close-range fight where sword and shield troops are useful you probably don't want to be using chemical weapons.
1) Momentum is one way through the field, but I suspect that the generators could be bedded in firmly enough so that anything capable of ripping them loose would kill the wearer from concussion anyway. Of course, just because it
can be made strong enough, doesn't mean it
is, particularly on cheaper equipment.
2) I like this idea, and I like your counter. I may use both, making it again something that "cheaper equipment" has issues about.
The other races don't give a damn about the gentle sensibilities of humans, and gasses aren't out of bounds, but against a competent foe there are countermeasures, countered easily enough in many cases to make it a complete waste of time and resources.
The Tai'Qu will not use any weapon that causes mass environmental damage (and will wage bitter regime-change war against anyone who does), the Annites would glass a world for the laughs once they got what they wanted from it, the Kerridan will do whatever is the most efficient to achieve their long-term goals. Which usually means not pissing off their trade-partners the humans without good cause.
All this is work (resumed) on some stuff from before. At that point named "The Terran Confederaton", now renamed "The Terran Accord" (because every man and his
dog apparently has a Terran Confederation)
Technology of the Terran Confederation
Aliens of the Terran Confederation
Fuck this is a long post. While I was typing it, I apparently got timed out. Glad I copied and pasted before trying to submit.