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EXACTO demonstrates first-ever guided .50-caliber bullets

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Re: EXACTO demonstrates first-ever guided .50-caliber bullets

#11

Post by fractalsea »

ArikBe wrote: post #9

The video and program page[1] don't reveal anything about how this works. I remember watching a documentary a few years ago on Discovery channel where this project was discussed. The bullet was essentially divided into a front and back portion, which could twist independently. The twisting then allows for corrections in the air. There's another design by Sandia labs where the bullets has little "fins" (like a missile…

That may explain how the target corrects its trajectory towards the actual target, but how does the bullet determine what the "actual target" is in the first place?

I would imagine this would be simple in test cases, but in the real world, what about a hostile target may differentiate it from a friendly ally that is nearby?

Re: EXACTO demonstrates first-ever guided .50-caliber bullets

#12

Post by percept »

ArikBe wrote: post #5
haptiK wrote: post #3

Earlier quoted context omitted.

ROFL /thread Seriously though. How do they plan to designate the target for this round?

I believe that targets are marked using a laser.

I thought they were marked by the incumbent powers that be!

Re: EXACTO demonstrates first-ever guided .50-caliber bullets

#13

Post by thefreeman »

ultimoo wrote: post #10

I wonder what is the technology behind this? Does the bullet have a small GPS module along with small motors that change the form of the bullet so that it can be guided by the rifle over radio frequency? What about the radio waves being interrupted or jammed etc. Or is it something more ground-breakingly advanced?

I have absolutely no idea. But it seems like these would be moving far too fast, and the maneuvering far too precise, for GPS tracking to be used.

Re: EXACTO demonstrates first-ever guided .50-caliber bullets

#14

Post by sschalk »

haptiK wrote: post #3
pyrocat wrote: post #2

Countdown to https://www.youtube.com/watch?v=7jVsQToSfag

ROFL /thread Seriously though. How do they plan to designate the target for this round?

Anyone seen Aliens? Anyone say M56 Smart Gun?

http://alienanthology.wikia.com/wiki/M56_Smart_Gun#Target_Tr...

"When powered up, the gun begins tracking targets via its infrared tracker mounted above the barrel. The tracker consists of a 256 x 256 element platinum-silicide focal plane array cooled to 770 degrees K by a tiny cryogenic gas cooler working on the Stirling principle. This system monitors a 30 degree cone in front of the gun and transmits high-resolution thermal images in the 8-10 um range to a miniature video display in the operator's eyepiece."

Thats all available technology - right now.

Re: EXACTO demonstrates first-ever guided .50-caliber bullets

#15

Post by singlow »

ricardobeat wrote: post #7
ArikBe wrote: post #5

Earlier quoted context omitted.

I believe that targets are marked using a laser.

If you can aim the laser, you can aim the weapon. This would certainly involve computer vision, makes it even more scary.

I think the idea is to automatically compensate for wind or other factors that would otherwise take the bullet on a path that is not on target. I think the part where they aim away from the target is just for demonstration.

Re: EXACTO demonstrates first-ever guided .50-caliber bullets

#16

Post by sitkack »

ricardobeat wrote: post #7
ArikBe wrote: post #5

Earlier quoted context omitted.

I believe that targets are marked using a laser.

If you can aim the laser, you can aim the weapon. This would certainly involve computer vision, makes it even more scary.

You can hit stuff that moves after the bullet is fired. It doesn't require computer vision.

Re: EXACTO demonstrates first-ever guided .50-caliber bullets

#17

Post by nostrademons »

ultimoo wrote: post #10

I wonder what is the technology behind this? Does the bullet have a small GPS module along with small motors that change the form of the bullet so that it can be guided by the rifle over radio frequency? What about the radio waves being interrupted or jammed etc. Or is it something more ground-breakingly advanced?

It says "optical guidance system" in the article. I suspect that the sniper needs to light up the target with a laser sight, and there's a small computer and microchip that adjusts the form of the bullet (per other commenter's description here) so that the laser dot is always directly ahead.

The article also says it's designed to compensate for "weather, wind, or target movement", so my assumption is that the sniper has to keep the target in their sight at all times, but it can compensate for the bullet ending up off-course after it has left the barrel.

Re: EXACTO demonstrates first-ever guided .50-caliber bullets

#18

Post by seany »

thefreeman wrote: post #13
ultimoo wrote: post #10

I wonder what is the technology behind this? Does the bullet have a small GPS module along with small motors that change the form of the bullet so that it can be guided by the rifle over radio frequency? What about the radio waves being interrupted or jammed etc. Or is it something more ground-breakingly advanced?

I have absolutely no idea. But it seems like these would be moving far too fast, and the maneuvering far too precise, for GPS tracking to be used.

Between 880-930meters/sec. I would think that a gps would have a hard time fitting inside a typical 50bmg bullet anyway. They only weigh about 45grams.

Re: EXACTO demonstrates first-ever guided .50-caliber bullets

#19

Post by trevyn »

fractalsea wrote: post #11
ArikBe wrote: post #9

The video and program page[1] don't reveal anything about how this works. I remember watching a documentary a few years ago on Discovery channel where this project was discussed. The bullet was essentially divided into a front and back portion, which could twist independently. The twisting then allows for corrections in the air. There's another design by Sandia labs where the bullets has little "fins" (like a missile…

That may explain how the target corrects its trajectory towards the actual target, but how does the bullet determine what the "actual target" is in the first place? I would imagine this would be simple in test cases, but in the real world, what about a hostile target may differentiate it from a friendly ally that is nearby?

http://en.wikipedia.org/wiki/Laser_guidance

Re: EXACTO demonstrates first-ever guided .50-caliber bullets

#20

Post by wiml »

fractalsea wrote: post #11
ArikBe wrote: post #9

The video and program page[1] don't reveal anything about how this works. I remember watching a documentary a few years ago on Discovery channel where this project was discussed. The bullet was essentially divided into a front and back portion, which could twist independently. The twisting then allows for corrections in the air. There's another design by Sandia labs where the bullets has little "fins" (like a missile…

That may explain how the target corrects its trajectory towards the actual target, but how does the bullet determine what the "actual target" is in the first place? I would imagine this would be simple in test cases, but in the real world, what about a hostile target may differentiate it from a friendly ally that is nearby?

Laser designator, I think.
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