Robo-Gunsight System Makes Sniper's Life Easier 265
An anonymous reader writes "Military and police marksmen could see their rifle sights catch up with the 21st century with a fiber-optic laser-based sensor system that automatically corrects for even tiny barrel disruptions. Factors such as heat generated by previously fired shots, to a simple bump against the ground can affect the trueness a rifle barrel. The new system precisely measures the deflection of the barrel relative to the sight and then electronically makes the necessary corrections. With modern high-caliber rifles boasting ranges of up to two miles, even very small barrel disruptions can cause a shooter to miss by a wide margin."
Re:Laser guidance? (Score:5, Informative)
small bullets could be made to be guided by laser
This is ambiguous, it could mean either of two completely different weapons systems:
First, we can consider an auto-aiming system with conventional "dumb", non-steered bullets. TFA discusses a tentative step in this direction, but it's easy to imagine a fully automated kind of system with a point-n-click interface. The rifle would be mounted on a computer-controlled, precision servo motor mount, with a a telescoped camera sighted along the barrel instead of a normal eyepiece. On a video monitor, the computer presents a crosshairs superimposed over a live camera image. The computer can incorporate various sources of ballistic data to correct the sight picture: sensors measuring (e.g.) barrel droop due to heat; a laser or microwave rangefinder for calculating elevation adjustments (b/c bullets drops as they travel); a wind gauge for calculating windage adjustments. If the computer performs real-time image analysis, it could also "mask" targets out from the background and analyze their motion, which would allow the operator's mouse aim to be pretty vague--kind of like a FPS game with an auto-aim cheat enabled.
With quality mechanics, sensors, and code, this kind of weapon could allow a novice to out-shoot a good trained military shooter, as long as the target is stationary. Based on existing, real-life systems that I've seen and worked with, I think this kind of weapon could be built, today, for less than $5,000 using slightly modified off-the-shelf equipment and software. Would it beat a trained, experienced military shooter? Maybe not, but I don't see any reason why the implementation couldn't be refined to that point--there's no theoretical reason why the pure man-plus-gun system has to be better.
The second possibility, here, is to introduce "smart" steerable bullets into the mix. Like a guided air-to-air missile, each bullet would be able to adjust its course in midair in order to track a target that is moving, or simply to correct for the normal vagaries ballistics. This kind of system's one clear superiority over dumb bullets is that it can account for variables that crop up *after* the bullet leaves the barrel. For instance, a particularly small, fast, and continuously, erratically moving target (say, a hummingbird at 1 km) can easily foil the best shooter, human or computer. The hummingbird can trivially move out of a bullet's path during the flight interval, and the position changes are too chaotic for meaningful predictions (unlike, say, a man walking along a stretch of road). If each bullet carries its own target-tracking sensor (like an air-to-air missile) or obeys remote commands from the gun's targeting system (like a TOW missile), then the possibility of hitting that hummingbird grows larger.
The mechanical implementation of steerable bullets is a bitch, though. The fundamental problem of non-powered, controlled flight is that course corrections increase drag and diminish your velocity. The more drastic of course changes you want, the more you hurt your aerodynamics, which proportionally hurts your kinetic energy, range, and damage potential. There may be a practical sweet spot, trading just a little power for just enough steering. Or, you might be forced to trade your unpowered bullets for powered rocket-like projectiles. Either way, you're talking about a hell of a lot of tough engineering R&D, like designing rocket engines or jet bodies, where you need an immense amount of experimental data and trial-and-error. To me, this sounds like big defense-contractor stuff--who else can afford time on a supersonic wind tunnel?
And then there's the problem of cramming a steering mechanism and whatever targeting control equipment you need into the space of a bullet. Electronics and mechanical designs may be hard or easy, but a sure way to make them maddeningly frustrating is to mandate an especially tiny physical package. Oh, and your mass di
Re:Dispersed Warfare versus Personal Courage (Score:5, Informative)
It turned out that a large number of soldiers never fired their weapons.
That "research", by S.L.A. Marshall [wikipedia.org], has been discredited. Read Col. Dave Hackworth's "About Face". Hackworth was a very good infantry commander and worked with S.L.A. Marshall in Vietnam, where Marshall was a journalist. Marshall made up a lot of what he wrote. His work reads like he was there when, most of the time, he wasn't.
The big breakthrough in training was in the late 1970s, when the U.S. Army developed the Multiple Integrated Laser Engagement System (MILES). This is the militarized version of laser tag. For the first time, soldiers fired their weapons during force-on-force exercises and the hits and misses were tallied. Previously, everybody made lots of noise with blanks and umpires randomly decided who died, like dungeon masters. With MILES, troops had to aim to hit in a combat training situation, because their performance was being measured. They got a lot better at it, and US infantry became much more effective as a result.
The problem was not soldiers failing to fire their weapons. It was firing but not hitting the enemy.
People underestimate the forces involved. (Score:4, Informative)
Take, for example, the M855 ball round [inetres.com] used in most US M4's. It has a muzzle velocity of 3025 feet per second. A standard M4 barrel [brownells.com] has a 1 in 7 inch twist, meaning the bullet completes a full rotation every 7 inches. Simple stoichiometry follows: 3025 feet/sec * 60 sec/min * 12 inches/1 foot * 1 rotation/7 inches = 311,142 rpm.
Remember those old videos of CD's exploding when they are rotated too fast, even when they are wrapped with wires to increase their tensile strength? Same applies here. As a matter of fact, this is used as a design feature: ball ammunition is designed to "tumble" end over end when it hits flesh which pushes the centrifugal forces on the bullet over the tensile strength of the bullet's jacket. This causes the bullet to fragment into tiny particles in the flesh, which results in the full force of the kinetic energy being deposited into the target.
Anyway, while the MEMS approach might be feasible from a size perspective, imagine the forces operating on one of these fins and the energy required to move any given fin even a tiny amount when it is feeling the pressures involved while moving through a fluid at 311 krpm. Now imagine what kind of materials would be necessary to implement this without the fin deforming or the armature of the fin simply shearing off.
These are cool ideas, but I think the physics & materials science aren't there.