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Relative positioning sensor question (With Picture)

  1. Nov 15, 2014 #1
    So I've been researching whatcould be the sensor/s that would do what the picture depicts:
    I have camera A behind camera B. What I'm trying to achieve is: to point the position of camera B when B passes on the field of view of A.

    When B pases in front of camera A the Screen of camera A will graphically indicate is position. If you have ever played with Combat Flight Simulator you know what I'm talking about.

    I would connect this sensor (as part of a board) and display the readings on the screen the same way an OSD does it.

    I've been looking at the way remote controls work and infrared sensor sounds like an option but I would like to hear your thoughts on this.

    Just so you know I'm a sophomore Mechanical engineering student so this is not my area of expertise.
  2. jcsd
  3. Nov 15, 2014 #2


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    I'm a bit confused about something. Does A need to detect B via some sort of broadcast/receiver arrangement? Why not simply 'see' it?

    A can actually see B. If B simply had a piece of magenta (or whatever) tape stuck to it, A would pick it up, and the software could substitute an icon where it detects any magenta.
  4. Nov 15, 2014 #3
    Thanks a lot for your suggestion Dave.

    That is what I'm thinking but I'm quite ignorant of the different ways I could achieve it.

    I was told that to see it could be a good solution to it. My concern is the background (outdoors) and range. How many pixels needs the magenta be to be detected? The camera I'm going to be using it is something like this. How do you think the resolution of the camera could affect the range or detection of the magenta? Does light conditions like a cloudy day or a very sunny day will affect the accurate detection of the magenta? Thanks Dave
  5. Nov 15, 2014 #4


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    True, a passive emitter (such as a coloured patch) will be less effective than an active emitter.

    But the thing is, you're going to have the same challenges with direction and distance regardless of what you receiving channel you choose. What receiving system will have the resolution to detect direction and distance? A radio receiver won't do that unless you have some sort of image anyway. So, perhaps take advantage of the current hi-rez (optical) imaging system you already have.

    But you can switch to an active broadcaster. Use infra-red LEDs. Does the camera you have in mind see into the near IR?

    It's all going to come down to the recognition software anyway. You should be able to get the software to filter for just IR wavelengths.

    This is how the Wii system works.

    The Wii has a configuration setting that will show you what its sensor bar sees. The sensor only sensitive to the freq that the controllers emit. So, its image of your living room looks like this. That is an actual, real-time video image of someone's living room. Wave the controllers and those dots will wave too.

  6. Nov 15, 2014 #5
    That is very cool Dave.
    It might have a filter like most cameras but I'll check the specs.

    I just found this diode but the beam angle is way too narrow. I would need something with a wider beam.
    ir sensor .jpg

    This is what you mean right?

    What kind of software could make sense of the IR signals?
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