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Self-guided bullets

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dragon
 Post subject: Self-guided bullets
PostPosted: 2012-01-31 10:52am 

Sith Marauder


Joined: 2004-09-23 04:42pm
Posts: 3804
Too cool or what

Quote:
Engineers at Sandia National Labs in New Mexico have developed laser-guided bullets.

Red Jones and Brian Kast produced the dart-like 100mm-long projectile to hit laser-designated targets at 2,000m.

The design includes an optical sensor in the nose to detect the laser spot on a target.

Data from this goes to an on-board 8bit microcontroller which runs an algorithm to command the electromagnetic actuators which operate the fins.

The rifling that spins normal bullets in flight to stabilise them had to go.

Instead, the bullet is fired from a smooth-bore barrel and flies straight due to its aerodynamically stable design, with centre of gravity in front of the fins.

According to aerodynamic, said Jones, under conditions where an unguided bullet could miss a target at 1,000m by 9m, the guided bullet would get within 200mm.

Plastic sabots (shrouds to make the bullet fit the bore) provide a gas seal and protect the fins until they drop off as it leaves the barrel.

There is no inertial measuring unit - no gyros or accelerometers.

Instead, the researchers found that the bullet's relatively small size when compared to guided missiles "is helping us all around. It's kind of a fortuitous thing that none of us saw when we started," said Jones.

As the bullet flies, it pitches and yaws at a rate based on its mass and size, said Sandia. In larger guided missiles, the rate of flight-path corrections is relatively slow, so each correction needs to be very precise because fewer corrections are possible during flight.

But "the natural body frequency of this bullet is about 30Hz, so we can make corrections 30 times per second. That means we can overcorrect, so we don't have to be as precise each time," Jones said.

The bullet can reach Mach 2.1 using commercial gunpowder and "the researchers are confident it could reach standard military speeds using customised gunpowder," said Sandia. While engineering issues remain, "we're confident in our science base and we're confident the engineering-technology base is there to solve the problems."



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Purple
 Post subject: Re: Self-guided bullets
PostPosted: 2012-01-31 04:41pm 

Jedi Council Member


Joined: 2010-04-20 08:31am
Posts: 2354
Location: In a purple cube orbiting this planet. Hijacking satellites for an internet connection.
I don't really see much use for this. I mean it's cool and all. But that's it. Under realistic conditions it will always be better (and cheaper) to just throw a dozen normall bullets down range instead of carefully designating the target for one like this.
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spaceviking
 Post subject: Re: Self-guided bullets
PostPosted: 2012-01-31 04:45pm 

Jedi Knight


Joined: 2008-03-20 05:54pm
Posts: 850
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Rabid
 Post subject: Re: Self-guided bullets
PostPosted: 2012-01-31 06:43pm 

Jedi Knight


Joined: 2010-09-18 05:20pm
Posts: 891
Location: The Land Of Cheese
RE : the usefulness of a guided bullet :

I can see this used in burst-capable sniper precision rifles, to compensate for the increased ammo spread resulting from firing a burst. Imagine : the spotter illuminate the target, and the shooter fire a burst of 3 to 5 guided bullets in less than second. The result could be really nasty.

Mounted on an assault rifle, it could also be used to compensate for a moving target : just keep the laser designator on the target and the bullets should correct their trajectory.
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Darmalus
 Post subject: Re: Self-guided bullets
PostPosted: 2012-01-31 07:37pm 

Jedi Knight


Joined: 2007-06-16 09:28am
Posts: 843
Location: Mountain View, California
I could see this being really useful for vehicles. A lot of gunship videos tend to show a ton of misses before any hits.
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Lord of the Abyss
 Post subject: Re: Self-guided bullets
PostPosted: 2012-01-31 09:22pm 

Village Idiot


Joined: 2005-06-15 12:21am
Posts: 4022
Location: The Abyss
It seems to me that a pistol version would be useful. I've always been told that one of the problems with pistols is that they aren't as accurate as rifles; this should help with that.
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Dave
 Post subject: Re: Self-guided bullets
PostPosted: 2012-01-31 09:38pm 

Jedi Knight


Joined: 2004-02-07 12:55am
Posts: 901
Location: Kansas City, MO
I don't think these qualify as 'self-guiding'; the target has to be illuminated with a laser, and the bullet doesn't provide the laser.

Someone on slashdot was suggesting drone-mounted sniping. Identify target with camera, mark target with laser, shoot target.

And finally, a link to the actual Sandia National Labs press release
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dragon
 Post subject: Re: Self-guided bullets
PostPosted: 2012-01-31 10:23pm 

Sith Marauder


Joined: 2004-09-23 04:42pm
Posts: 3804
Be good for snipers as they usally have a spotter, every day combat no.
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Hawkwings
 Post subject: Re: Self-guided bullets
PostPosted: 2012-01-31 10:38pm 

Sith Devotee


Joined: 2005-01-28 10:30pm
Posts: 3372
Location: USC, LA, CA
Or, over the hill sniping. Have someone lase the target, then the triggerman fires from behind a hill, and the bullet follows the path to the target.
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dragon
 Post subject: Re: Self-guided bullets
PostPosted: 2012-01-31 11:57pm 

Sith Marauder


Joined: 2004-09-23 04:42pm
Posts: 3804
Now all we need is the replay button from 5th element to add to it :D
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Bedlam
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 04:28am 

Jedi Knight


Joined: 2006-09-23 11:12am
Posts: 908
Location: Edinburgh, UK
Hawkwings wrote:
Or, over the hill sniping. Have someone lase the target, then the triggerman fires from behind a hill, and the bullet follows the path to the target.


Would this actually be any different to just shooting them? Someone has to put themselves in harms way be it the laser person or the sniper themselves. I supose the laser might be smaller and easier to conseal but when it comes to saving your people in a combat situation there seems to be no improvement.
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PeZook
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 04:35am 

Emperor's Hand


Joined: 2002-07-18 06:08pm
Posts: 13237
Location: Poland
Bedlam wrote:
Would this actually be any different to just shooting them? Someone has to put themselves in harms way be it the laser person or the sniper themselves. I supose the laser might be smaller and easier to conseal but when it comes to saving your people in a combat situation there seems to be no improvement.


Except the lasing can be done by a drone, or the people who are being shot at. It's not a wonderweapon, but it will totally have its uses for snipers (extending range and making those extreme range shots waaaaaaay easier - killing people at 1.8 kilometres is something only extremely good snipers do today, with a bullet like that suddenly everyone can), drones (sniping terrorizers from 2 kilometres up in the sky instead of blowing up entire groups? Yes please!), and quite possibly a range of spin-off technologies like ultra-precise grenade launchers (taking fire from that window 500 metres away? BOOM, window gone, one grende expended).
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bilateralrope
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 04:39am 

Jedi Council Member


Joined: 2005-06-25 06:50pm
Posts: 2149
Location: New Zealand
How well would these bullets do if they see two targeting lasers ?
One pointing at the target, and another pointing elsewhere to make the bullet miss.
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PeZook
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 04:44am 

Emperor's Hand


Joined: 2002-07-18 06:08pm
Posts: 13237
Location: Poland
bilateralrope wrote:
How well would these bullets do if they see two targeting lasers ?
One pointing at the target, and another pointing elsewhere to make the bullet miss.


Presumably the sensor is keyed to specific frequencies/other characteristics of the laser spot, which means the enemy would have to know these parameters and then design, make and deploy man-portable countermeasures.
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bilateralrope
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 04:54am 

Jedi Council Member


Joined: 2005-06-25 06:50pm
Posts: 2149
Location: New Zealand
PeZook wrote:
bilateralrope wrote:
How well would these bullets do if they see two targeting lasers ?
One pointing at the target, and another pointing elsewhere to make the bullet miss.


Presumably the sensor is keyed to specific frequencies/other characteristics of the laser spot, which means the enemy would have to know these parameters and then design, make and deploy man-portable countermeasures.

How hard is it to change a lasers frequency, or any of these other characteristics ?

Or to produce multiple weapons using lasers that are different enough that they won't fool each others bullets ?
Though different lasers for each weapon means the bullets would have to be keyed in to the specific weapon they are fired from.
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PeZook
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 05:02am 

Emperor's Hand


Joined: 2002-07-18 06:08pm
Posts: 13237
Location: Poland
bilateralrope wrote:
Or to produce multiple weapons using lasers that are different enough that they won't fool each others bullets ?


Why would you do that? It's not something you will be throwing hundreds of around (if for no other reason, than think of the expense!). It should be perfectly possible to use a standardized laser designator, especially if the sensor doesn't have a radically wide field of view.

bilateralrope wrote:
Though different lasers for each weapon means the bullets would have to be keyed in to the specific weapon they are fired from.


If you have the entire squad using laser-guided bullets exclusively, then yeah, that might become a problem: but most likely, those things will be a "silver bullet" kind of thing, used for specific occasions (like shooting a high ranking officer from way beyond any reasonable sniper range, taking out machine gun crews, that sort of stuff)
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Purple
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 08:18am 

Jedi Council Member


Joined: 2010-04-20 08:31am
Posts: 2354
Location: In a purple cube orbiting this planet. Hijacking satellites for an internet connection.
Lord of the Abyss wrote:
It seems to me that a pistol version would be useful. I've always been told that one of the problems with pistols is that they aren't as accurate as rifles; this should help with that.

Pistols are so inaccurate over longer ranges because their bullets are stubby and fat and fired at a relatively low (compared to rifles) velocities out of very short barrels. Hence they tend to fallow a flight trajectory that is not good for long range flight. Adding a guidance system won't change a thing there unless you completely change the shape of the bullet and attach a rocket motor or something to give it extra speed.

Hawkwings wrote:
Or, over the hill sniping. Have someone lase the target, then the triggerman fires from behind a hill, and the bullet follows the path to the target.

I wonder if a bullet fired at an indirect trajectory over long range would retain enough energy to actually kill someone. I mean, what you would in essence be doing is controlling the flight path of a falling bullet. My guess is that it would be a hit and miss things in terms of actually killing someone.


Now what I would do with this is mount the laser designator on a sniper rifle. Over regular sniper ranges (or even up to 2km), the bullet won't be flying for more than a few seconds. That I think is not nearly enough time to have the spotter guide the round on target. However it is enough time for the shooter him self to just keep his aim on what ever he wants to kill and thus keep the trajectory of the round steady. What this would do is basically eliminate the need to account for wind or distance when aiming, possibly even for a lead on a slowish moving target like say a human walking.
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madd0ct0r
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 09:31am 

Sith Devotee


Joined: 2008-03-14 07:47am
Posts: 3403
won't the bullet get in the way of it's own gun's laser pointer then?
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Rabid
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 09:53am 

Jedi Knight


Joined: 2010-09-18 05:20pm
Posts: 891
Location: The Land Of Cheese
madd0ct0r wrote:
won't the bullet get in the way of it's own gun's laser pointer then?

I dunno. What do you think ?

(trajectory of the Laser Guided Bullet as shown by putting a tiny LED on it and shooting the photo at night)
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Purple
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 10:17am 

Jedi Council Member


Joined: 2010-04-20 08:31am
Posts: 2354
Location: In a purple cube orbiting this planet. Hijacking satellites for an internet connection.
Is this thing beam riding or beam seeking? As in, does the projectile ride the beam or simply try and aim it self so that it hits the point the beam is pointed at. If it is the later (as I believe it is) than it should be no problem.
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Adamskywalker007
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 05:37pm 

Padawan Learner


Joined: 2004-03-27 05:51am
Posts: 432
Bedlam wrote:
Would this actually be any different to just shooting them? Someone has to put themselves in harms way be it the laser person or the sniper themselves. I supose the laser might be smaller and easier to conseal but when it comes to saving your people in a combat situation there seems to be no improvement.

The difference is that it is much easier to track a fired sniper rifle than a laser designator. It increasingly easy to track a sniper's shots today with acoustic tracking systems, see here: http://scienceline.org/2007/01/tech-hsu-guns/ while the laser would be much harder to detect and does nothing to give away the spotter's position.
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Sea Skimmer
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-01 07:04pm 

Yankee Capitalist Air Pirate


Joined: 2002-07-03 11:49pm
Posts: 35348
Location: Passchendaele City, HAB
bilateralrope wrote:
How hard is it to change a lasers frequency, or any of these other characteristics ?


The way laser guided weapons avoid mutual interference is you adjust the pulse repetition rate on different designators and set the weapons accordingly. None of the designators in use actually emit a continuous laser beam. Designing a laser which can adjust frequency would be much harder; most types of lasers simply cannot do that as I recall.

Purple wrote:
Is this thing beam riding or beam seeking? As in, does the projectile ride the beam or simply try and aim it self so that it hits the point the beam is pointed at. If it is the later (as I believe it is) than it should be no problem.


Seeks the reflection. The bullet blocking its own beam isn’t likely to matter as it bounces around; and even if it did it’d be easy enough to have your spotter do the designating from close beside you. The biggest problem I see is the laser beam width limits the ultimate accuracy; but at 2km that should still be a lot smaller then a human torso.

Cost won’t matter as long as it costs less then the Hellfire and Javelin missiles the US already freely fires to kill random single people.

Adamskywalker007 wrote:
The difference is that it is much easier to track a fired sniper rifle than a laser designator. It increasingly easy to track a sniper's shots today with acoustic tracking systems, see here: http://scienceline.org/2007/01/tech-hsu-guns/ while the laser would be much harder to detect and does nothing to give away the spotter's position.


It’s much easier to track the laser designator actually; certainly laser warning systems are much older technology. Precision systems exist which can identify the laser location itself; most systems just give a bearing based warning. Also most kinds of laser designators are some kind of infrared laser and you can actually see the beam using night vision goggles. But you’re only designating for a very short period with any kind of laser guided weapon, which reduces the chances of being detected.

Those acoustical gunfire locators just give a bearing, with non trivial inaccuracy to the users. Much better acoustical systems are being worked on, which would network sensors on multiple vehicles together and cross reference the bearings and time of arrival to generate a relatively accurate location of the shooter. However an acoustical system will always have the problem that it only provides warning after the sound of the bullet arrives, which being mach 1 is going to be much slower then the mach 2-3 bullet. So the bullet has impacted by the time you hear it and the first guy may already be dead. A laser designator would be detected prior to impact which might actually give you time to duck and make the enemy miss. What's more the sounds of battle, explosions and your own outgoing fire ect.. can make acoustical systems ineffective. People used to commonly use acoustical systems, of a much larger size (base lines measured in kilometers) to locate enemy artillery fire as early as WW1 but the technology largely, but not completely died out because of interference problems like that making them less useful the more the enemy fired.

However most nations and sub national groups are never going to have any of this kind technology field deployed on a widespread scale, and especially not in a man portable form because of the power and weight involved. A guided sniper rifle is a weapon for small wars, in big wars the main value of snipers is actually as covert observers for artillery and air strikes. You don’t really want them shooting that much least it compromise this role.
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Zaune
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-02 08:55am 

Sith Marauder


Joined: 2010-06-21 11:05am
Posts: 3823
Location: In Transit
What I want to know is, how much is the weapon and its asociated ammunition going to cost, and how does its circular error probability compare to conventional ammunition such as .50 BMG or 14.5mm?
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Rabid
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-02 03:49pm 

Jedi Knight


Joined: 2010-09-18 05:20pm
Posts: 891
Location: The Land Of Cheese
If I recall correctly, in the article they claim a CEP of ~20 centimetres compared to ~9 meters for conventional munitions at a 2km range or something.

As for the price, in the link someone above posted, the people of the XM-25 project claimed their grenades with an integrated electronic "flight computer" would cost roughly $12 a piece once mass produced. So for a small silver-bullet of the degree of electronic/mecatronic complexity and miniaturization its performances suggest, I'd ass-pull a guess for a unitary price of ~20-40 dollars if mass-produced, or ~100-200 dollar a piece if it isn't mass-produced and made "on demand" only.

Compare with the cost-effectiveness of the other solution(s) you mentioned, and see if this "silver-bullet" is an improvement as far as cost-effectiveness goes for its intended purpose. I can't tell myself. But in the other hand, if the US's DoD felt like sinking, like, a billion dollar in the project maybe it was because they felt a need for it ? Or maybe they just did it for the lulz.
I honestly don't know.


Edit : also, it may not be cost-effective, but intended for cases where you absolutely, positively need that one bastard dead ?
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Zaune
 Post subject: Re: Self-guided bullets
PostPosted: 2012-02-02 04:24pm 

Sith Marauder


Joined: 2010-06-21 11:05am
Posts: 3823
Location: In Transit
Rabid wrote:
If I recall correctly, in the article they claim a CEP of ~20 centimetres compared to ~9 meters for conventional munitions at a 2km range or something.

the original article wrote:
According to aerodynamic, said Jones, under conditions where an unguided bullet could miss a target at 1,000m by 9m, the guided bullet would get within 200mm.

You're off by nearly 50%; 2km is the weapon's claimed maximum range, and the CEP at the upper end of that is unspecified. And I have to admit I'm curious as to what those conditions might be.
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