Directed energy weapons

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avianmosquito
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Re: Science fiction forum: Directed energy weapons

Post by avianmosquito »

PeZook wrote:A pistol is also an infantry weapon too, and so is an 85mm mortar. Show me a soldier who can consistently throw a hand grenade into a window at 500 meters (or 100, whatever), and then we can compare both systems.
Point taken.
avianmosquito wrote:Wrong. When the military tells you something's range, divide it by 5. That'll be the real effective range. Conveniently, it coincides almost perfectly with the range of the redox underslung, (100m) meaning that yes, they are almost perfectly comparable.
PeZook wrote:Why? Is there a reason for this ridiculous rule?
Because they base it off of the range an elite soldier can hit a stationary target with no wind or intervening obstacles. In combat, you have a much poorer shot, shooting a moving target, in wind, with dust, rain or other environmental issues obscuring vision, shooting over or around objects.
PeZook wrote:Just how did you arrive at those temperatures, and why do you think the grease will stay at 800 kelvin until it lands on somebody?
It was a guess, I got 800k from my youth, playing around with a thermite explosive and the grease in the dumpster behind a mcdonalds.
PeZook wrote:Obviously I meant something more advanced than literally plastic: something like nomex, which doesn't melt or burn but simply starts to decompose at 650 kelvin. Space-age societies could probably produce something even better.
It would more likely be polycarbonate. It's easy to make, and is both light and strong.
avianmosquito wrote:Also, if you're within the 2.5m kill radius, expect to catch upwards of 5 grams and expect it to top 1000k. Not only that, the blast should be enough to stun in and of itself. Finally, the person who fired isn't going to leave it there, he'll shoot another soldier, then another and another until he runs out of clear shots or runs out of ammunition. That's as many as 5 people splattered, and one mess of a greasefire.
PeZook wrote:Uh...are you seriously saying the grease will burn at close to the melting point of steel?

And I wouldn't count on being able to hit five people in close succession at any kind of range, unless this thing is also an automatic weapon.
Steel melts at 2000k, not 1000. Also, it'll only be at this temperature for a second or so, hence why the grease at 6m is 200 degrees cooler.

And the weapon is semi-automatic. Target, fire, target, fire. Works better than an automatic because they don't just spray the blasts all over the place and miss 4/5.
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Re: Directed energy weapons

Post by Serafina »

Because they base it off of the range an elite soldier can hit a stationary target with no wind or intervening obstacles. In combat, you have a much poorer shot, shooting a moving target, in wind, with dust, rain or other environmental issues obscuring vision, shooting over or around objects.
I guess that's why snipers regulary score hits at greater ranges than the stated range of their rifles.
Same goes for other weapon systems.

Your "divide by five" rule is simply preposerous.
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Re: Directed energy weapons

Post by avianmosquito »

Serafina wrote:
Because they base it off of the range an elite soldier can hit a stationary target with no wind or intervening obstacles. In combat, you have a much poorer shot, shooting a moving target, in wind, with dust, rain or other environmental issues obscuring vision, shooting over or around objects.
I guess that's why snipers regulary score hits at greater ranges than the stated range of their rifles.
Same goes for other weapon systems.

Your "divide by five" rule is simply preposerous.
5 may be a supreme exagerration, but you should still take the rated range with a grain of salt.

Furthermore, rifles are tested as they are manufactured, not as they are used. In combat, you get something to help improve the effective range, it's called a "scope."
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Re: Directed energy weapons

Post by loomer »

You know they also test purpose built marksman and sniper platforms with scopes, right? Not iron sights? Because they're designed to be used with a scope?
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Re: Directed energy weapons

Post by PeZook »

loomer wrote:You know they also test purpose built marksman and sniper platforms with scopes, right? Not iron sights? Because they're designed to be used with a scope?
Also, the XM-25 has that suspicious bulge on the top, which might or might not be a sophisticated computerized scope. I wouldn't know :P
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Re: Directed energy weapons

Post by mdiinican »

Hopefully this thread isn't so dead that this counts as thread necromancy. About half a month?

Anyway, my idea is for a variable frequency pulsed laser weapon with some fancy optics and computer controls. In the space of a tiny fraction of a second it would carry out a couple of steps before actually firing. It would first shine a low powered laser beam onto the target and use the known frequency of the beam to calibrate for atmospheric effects. Then it would fire a single full power pulse and use the weapon's optics to take a picture of the EM spectra emitted by the gas or plasma vaporized from the target. That would be used for spectroscopic analysis in order to determine what the target is made of. Then the weapon's computer would adjust the frequency of the laser to be optimal for it's power level and the target's composition.

The laser is pulsed so that the material being ablated by the laser doesn't interfere with the beam.
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Re: Directed energy weapons

Post by Coyote »

1- Are you sure you want to be associated with an avianmosquito thread so soon in your SDN arrival? :wink:

2- Hopefully the target in your description isn't moving, or there is no cover/concealment or even foliage in the way that might delay the reading or give a false reading.. also, if the vehicle is caked in dirt. mud, snow or grime (as combat vehicles tend to get) you'd get an erroneous reading. Plus, once the enemy finds out about this weapon, special paints or bolt-on armors can be added to foil the readings and analysis. Basically, be wary of any technology that relies on a compliant/stupid enemy to work.

3- Aaaannnd don't take this personally, but could a mod do a li'l ol' IP check? Just to make sure...? :?
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Re: Directed energy weapons

Post by mdiinican »

Coyote wrote:1- Are you sure you want to be associated with an avianmosquito thread so soon in your SDN arrival? :wink:

2- Hopefully the target in your description isn't moving, or there is no cover/concealment or even foliage in the way that might delay the reading or give a false reading.. also, if the vehicle is caked in dirt. mud, snow or grime (as combat vehicles tend to get) you'd get an erroneous reading. Plus, once the enemy finds out about this weapon, special paints or bolt-on armors can be added to foil the readings and analysis. Basically, be wary of any technology that relies on a compliant/stupid enemy to work.

3- Aaaannnd don't take this personally, but could a mod do a li'l ol' IP check? Just to make sure...? :?

1. His threads always end up so amusing. I think it's because he's not actually trolling, but just posting some rather bad ideas.

2. I guess it could also examine the spectra of what gets kicked up with each pulse while firing, and adjust the frequency in real time. Then it would just figure out the best frequency to cut through the paint, dirt, whatever, cut through it, and then change to start cutting metal or ceramic. Moving targets probably wouldn't be too much of an issue because the laser is probably going to be pulsed at high kilohertz to low megahertz frequency for most materials. Actually calculating it would be pretty hard though. I know nothing about how fast vaporized metal/ceramic/flesh flies away from a surface.

3. I've got absolutely no objections, but I don't know how it would help. I've moved to a different county and changed computers probably thrice since I was here last, I think it was back in like '04-'05. I assure you, I'm not a sock of any active member. I post over on Spacebattles, but recently the topics there just haven't interested me as much as the ones I've seen over here.
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Re: Directed energy weapons

Post by Sea Skimmer »

mdiinican wrote:Hopefully this thread isn't so dead that this counts as thread necromancy. About half a month?

Anyway, my idea is for a variable frequency pulsed laser weapon with some fancy optics and computer controls. In the space of a tiny fraction of a second it would carry out a couple of steps before actually firing. It would first shine a low powered laser beam onto the target and use the known frequency of the beam to calibrate for atmospheric effects. Then it would fire a single full power pulse and use the weapon's optics to take a picture of the EM spectra emitted by the gas or plasma vaporized from the target. That would be used for spectroscopic analysis in order to determine what the target is made of. Then the weapon's computer would adjust the frequency of the laser to be optimal for it's power level and the target's composition.

The laser is pulsed so that the material being ablated by the laser doesn't interfere with the beam.
Technology like that is being worked on, it might very well be in service but most information is classified. The US Air Force has been interested in remote sensing lasers which could identify the composition of targets, destructively is necessary ever since the Gulf War. That war highlighted a major limitation of our reconnaissance capabilities. We could identify chemical or biological weapons storage bunkers by the design of the bunker in photos. But we had no way of telling if one was empty or filled, and likewise had no way of identifying chemical or biological ammunition in the field. Since chemical or bio weapons don't give secondary explosions, the bunkers just blew up when bombs hit them and that was all we knew.

A remote sensing laser which could probe an explosion cloud, or burn into a munition on the ground and then identify what its made of or what it contained contents was thus highly desirable. Advances in civilian remote sensing strongly suggest the air force has something that can do this by now, and making it man portable is not out of reason at all. Adding a high power laser capability to destroy the target is icing on the cake, but we are still a long ways from being able to make a laser with that kind of firepower portable for anything less then a C-130 sized aircraft. I don't know how feasible major frequency changes are for a laser though, nor how much of a difference that would really make.

But then even a weak manpack laser with target identification capability would be damn nice. It could tell troops if trash on a road or trail has explosives inside of it for example without requiring as much firepower as you would need to just burn up the trash or explode said explosives.
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Re: Directed energy weapons

Post by Simon_Jester »

mdiinican wrote:1. His threads always end up so amusing. I think it's because he's not actually trolling, but just posting some rather bad ideas.
Well, he's been banned now because of a very stupid affair where either he cranked his stupidity and creepiness and lying up to eleven and got banned when he tried to cover it up with an even bigger lie... or because he gave his stupider, creepier, bigger liar of a friend access to his account and got banned for that.
2. I guess it could also examine the spectra of what gets kicked up with each pulse while firing, and adjust the frequency in real time. Then it would just figure out the best frequency to cut through the paint, dirt, whatever, cut through it, and then change to start cutting metal or ceramic. Moving targets probably wouldn't be too much of an issue because the laser is probably going to be pulsed at high kilohertz to low megahertz frequency for most materials. Actually calculating it would be pretty hard though. I know nothing about how fast vaporized metal/ceramic/flesh flies away from a surface.
I've seen some interesting calcs on laser weapons over on Atomic Rocket, if you're familiar with that.

The real problem is making a frequency-agile laser. The only way I know to do that is with a free electron laser, which is going to be kind of bulky due to acceleration distance constraints. The Navy is working on them for point defense applications, but they're planning to put them on hundred-meter ships, so they have more room to play with.
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Re: Directed energy weapons

Post by mdiinican »

Anyway, I'm not too hot on the idea of directed energy weapons at a small arms level. The kind of miniaturized power supply that could make that work also makes a lot of more interesting things practical as well. For the foreseeable future, bullets and explosives do their job really well.
Simon_Jester wrote:
mdiinican wrote:1. His threads always end up so amusing. I think it's because he's not actually trolling, but just posting some rather bad ideas.
Well, he's been banned now because of a very stupid affair where either he cranked his stupidity and creepiness and lying up to eleven and got banned when he tried to cover it up with an even bigger lie... or because he gave his stupider, creepier, bigger liar of a friend access to his account and got banned for that.
Ah, I haven't lurked through all his threads yet. Laughing at page 2 of his headshots fiasco at the moment.
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Re: Directed energy weapons

Post by Norade »

mdiinican wrote:Anyway, I'm not too hot on the idea of directed energy weapons at a small arms level. The kind of miniaturized power supply that could make that work also makes a lot of more interesting things practical as well. For the foreseeable future, bullets and explosives do their job really well.
Simon_Jester wrote:
mdiinican wrote:1. His threads always end up so amusing. I think it's because he's not actually trolling, but just posting some rather bad ideas.
Well, he's been banned now because of a very stupid affair where either he cranked his stupidity and creepiness and lying up to eleven and got banned when he tried to cover it up with an even bigger lie... or because he gave his stupider, creepier, bigger liar of a friend access to his account and got banned for that.
Ah, I haven't lurked through all his threads yet. Laughing at page 2 of his headshots fiasco at the moment.
Yeah, avoid that thread if you value your sanity, he goes to some really creepy Jerry Springer shit at the end that may lower IQ permanently.
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Re: Directed energy weapons

Post by Coyote »

I don't know about that; right now it seems to be the "must-see comedy act" of the board right now. :lol:

Yeah, mdiinican, it'll be awhile before bullets are replaced, and I think even in a future where direct-energy weapons at an infantry level dominate, there'll still be a niche for slug-throwers of various types.
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In Communism, there is no Government, so the Workers are free to exploit the Bosses.
So in Libertarianism, man exploits man, but in Communism, its the other way around!

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Re: Directed energy weapons

Post by adam_grif »

Yeah, mdiinican, it'll be awhile before bullets are replaced, and I think even in a future where direct-energy weapons at an infantry level dominate, there'll still be a niche for slug-throwers of various types.
Indeed. If we're talking pulsed lasers that make peoples limbs explode, you can't exactly bung on a supressor.
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Re: Directed energy weapons

Post by Simon_Jester »

I'm not sure you'd need to; lasers are pretty quiet.
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Re: Directed energy weapons

Post by PeZook »

Simon_Jester wrote:I'm not sure you'd need to; lasers are pretty quiet.
Until the guy's arm explodes and he falls over screaming his head off :P

Of course, supressed weapons have the exact same problem, but at least they don't leave a nice bright path of heated air for even basic sensors to follow :D

I'd imagine the specialized applications will be things like artillery (you can't replicate it with direct energy weapons, though you an defend against it), demolitions, shooting at enemies in defilade and under cover, etc.
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Re: Directed energy weapons

Post by adam_grif »

The lasers are, yeah, but the exploding limbs aren't.

Exerpt from Atomic Rockets:

(note: discussing pulsed lasers)
Remember that the temporary cavity caused by the explosions only lasts a few milliseconds, so the beam has to have completed its work of piercing the target at this time. The individual explosions will be too closely spaced (microseconds apart) to be individually audible. Since shocks are always supersonic to the air in their path, and subsonic to the moving air left behind them, multiple subsequent shocks from the same source tend to merge into one stronger shock. Thus, each pulse probably makes one bang. The bang comes from a series of explosions whose total energy is about the same as that of the gunpowder detonating in a firing rifle, so it will probably be about as loud.
This is to say, it will still make a sound equivelant to a gunshot if it has gunshot equivelant energy. Except the sound comes from the target, instead of the weapon firing it. This is good in the sense that the shooter can't be identified by a system like Boomerang, but bad because there's nothing you can do to stop it from occuring except dialing your power down, which also hugely decreases destructiveness.

So, for wetwork, slugthrowers may be preferred in niche applications.
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Re: Directed energy weapons

Post by GrandMasterTerwynn »

mdiinican wrote:Anyway, I'm not too hot on the idea of directed energy weapons at a small arms level. The kind of miniaturized power supply that could make that work also makes a lot of more interesting things practical as well. For the foreseeable future, bullets and explosives do their job really well.
With the theoretical increases in energy density offered by some of the ongoing research into lithium-ion batteries, you actually could build a man-portable anti-personnel laser (with anti-personnel being defined as 'rendering said personnel dead.') The battery pack will, of course, be quite large, and the aperture of the laser will need to be bigger than the bore of a grenade launcher if you want any useful range at all. Of course, when you throw in the required beam-stabilization system, target tracking optics, and active cooling system; you'll end up with something the size of the typical squad automatic weapon.

So, yeah, armies of the foreseeable future will still be shooting bullets at each other. The grenades, however, will probably get much smarter.
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