5 ms·

* Locating moving objects that could be anything that can move at a speed, with Cheap Cameras Without Using AI or Radar

mapt 2y ago
Aerodynamics & engineering dictates that not many things can move at the speed/agility of a stealth fighter. If you've got a radar system already in place, "Stealth" is just the ones that don't also pop up on the radar.
- robocat 2y ago
  Presumably scattered radar receivers can detect faint reflections using similar correlation. Is there a background microwave radiation at shorter wavelengths that could be made into a camera that could see through clouds too? microwave is too long wavelength to make a small camera.
  - dingaling 2y ago
    > Presumably scattered radar receivers can detect faint reflections using similar correlation. Yes, multistatic radars are already in service. An advance on the concept is that the active transmitter can be placed outside anticipated weapons range and those within range are merely passive receivers. There have been proposals to build such systems that use 'oblivious' transmitter sources such as commercial radio broadcasts.
    - mikewarot 2y ago
      There was a project to extend/enhance the Kraken multi-SDR system that got yanked from GitHub, etc, because it tripped over ITAR in that it enabled passive radar. ITAR assumes the US leads the world in technology, and actively prevents us from catching up if we don't.
ajross 2y ago
Locating civilian, friendly and radar-visible aircraft is a solved problem though. So the distinction is only a matter of subtraction. No, in fact this kind of technique absolutely puts a hard limit on the value of "stealth" devices, which are purpose-designed to evade a very specific technology that was a warfare-changing innovation in the 1940's but is now pretty cheaply replaceable by consumer junk. The days of large manned aircraft are very much numbered, and armies that fail to see that are armies that are destined to lose.
- throwaway81523 2y ago
  If it's a clear day and the bottom of the airplane is painted blue, it could blend in with the sky. For that matter, didn't Wonder Woman have a transparent airplane? Aha, better yet, it was invisible! https://dc.fandom.com/wiki/Wonder_Woman%27s_Invisible_Plane https://dc.fandom.com/wiki/Wonder_Woman%27s_Invisible_Plane
  - ajross 2y ago
    Yes, because if there's one thing computer vision solutions have historically had trouble with, it's being fooled by paint. The ludditism in this thread is shockingly strong.
    - itishappy 2y ago
      CV systems absolutely do struggle with this... https://www.youtube.com/watch?v=U1MigIJXJx8 https://www.youtube.com/watch?v=U1MigIJXJx8
      - ajross 2y ago
        Yes, and that's considered a bug to fix, and can be. CV systems are widely applied to find camouflaged and obscured objects! Literally every automated wildlife camera is proof that this is a silly point.
        2y ago
echoangle 2y ago
I guess you’re pointing out that there’s no identification. But it’s still locating stealth fighters.
- nradov 2y ago
  It's really not. It's a toy demo of visually locating aircraft at relatively short range under ideal weather conditions. So what.

mapt 2y ago

Aerodynamics & engineering dictates that not many things can move at the speed/agility of a stealth fighter. If you've got a radar system already in place, "Stealth" is just the ones that don't also pop up on the radar.

robocat 2y ago
Presumably scattered radar receivers can detect faint reflections using similar correlation. Is there a background microwave radiation at shorter wavelengths that could be made into a camera that could see through clouds too? microwave is too long wavelength to make a small camera.
- dingaling 2y ago
  > Presumably scattered radar receivers can detect faint reflections using similar correlation. Yes, multistatic radars are already in service. An advance on the concept is that the active transmitter can be placed outside anticipated weapons range and those within range are merely passive receivers. There have been proposals to build such systems that use 'oblivious' transmitter sources such as commercial radio broadcasts.
  - mikewarot 2y ago
    There was a project to extend/enhance the Kraken multi-SDR system that got yanked from GitHub, etc, because it tripped over ITAR in that it enabled passive radar. ITAR assumes the US leads the world in technology, and actively prevents us from catching up if we don't.

ajross 2y ago

Locating civilian, friendly and radar-visible aircraft is a solved problem though. So the distinction is only a matter of subtraction. No, in fact this kind of technique absolutely puts a hard limit on the value of "stealth" devices, which are purpose-designed to evade a very specific technology that was a warfare-changing innovation in the 1940's but is now pretty cheaply replaceable by consumer junk. The days of large manned aircraft are very much numbered, and armies that fail to see that are armies that are destined to lose.

throwaway81523 2y ago
If it's a clear day and the bottom of the airplane is painted blue, it could blend in with the sky. For that matter, didn't Wonder Woman have a transparent airplane? Aha, better yet, it was invisible! https://dc.fandom.com/wiki/Wonder_Woman%27s_Invisible_Plane https://dc.fandom.com/wiki/Wonder_Woman%27s_Invisible_Plane
- ajross 2y ago
  Yes, because if there's one thing computer vision solutions have historically had trouble with, it's being fooled by paint. The ludditism in this thread is shockingly strong.
  - itishappy 2y ago
    CV systems absolutely do struggle with this... https://www.youtube.com/watch?v=U1MigIJXJx8 https://www.youtube.com/watch?v=U1MigIJXJx8
    - ajross 2y ago
      Yes, and that's considered a bug to fix, and can be. CV systems are widely applied to find camouflaged and obscured objects! Literally every automated wildlife camera is proof that this is a silly point.
      - 2y ago

echoangle 2y ago

I guess you’re pointing out that there’s no identification. But it’s still locating stealth fighters.

nradov 2y ago
It's really not. It's a toy demo of visually locating aircraft at relatively short range under ideal weather conditions. So what.