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Connecting a PTZ wireless IP camera to Proppeler — Parallax Forums

Connecting a PTZ wireless IP camera to Proppeler

mugurmugur Posts: 105
edited 2010-01-03 11:32 in Propeller 1
Hello, i am new here and i need an advice. I want to connect a wifi IP camera with proppeler. This camera has a built in web server and 2 motors that take care of the pan/tilt function. The zoom function is digital, no motors there. This also have audio.

The model is Linksys WVC200. I have opened the camera and the motors make me a bit confused. Even that they are not regular servos, the motors have a planetary gear box (for torque), and 4 wire to each motor. Also, getting the proppeler to communicate over the network using
the webserver will be great, if possible.

If anyone thinks this is possible and have any practical advice for me, please let me know.
Thank you for your time.

Comments

  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-01-02 21:41
    What is it you want the Propeller to do exactly?

    -Phil
  • mugurmugur Posts: 105
    edited 2010-01-02 22:09
    I want to be able to brodcast the video over net (like the camera does now) but the proppeler to move the camera motors (conditional) , not me, manualy from the browser.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-01-02 22:37
    I'm still missing the whole picture. From where will the Propeller get the commands to move the motors?

    -Phil
  • mugurmugur Posts: 105
    edited 2010-01-02 23:02
    Sorry Phil, i'm an idiot. The proppeler will get the commands from the sensors, example: when obstacle is met, the robot will search an alternate route and the camera will show that route before the robot will actualy move there. That's the very "short" description, the main issue is how i will command those tiny motors with 4 wires each, since i know nothing about them , and even worse, they are so tiny that i cannot see how to replace them.I really doubt that they are steppers thoug, they are really small.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-01-03 00:12
    Okay, got it now. With four wires they could well be steppers. Do you see anything on the PCB that looks like a dual H-bridge driver? It might be an IC, or it could be a bunch of transistors (eight per motor). Do you have a scope that you can use to look at the waveforms going to the motors as they move?

    -Phil
  • w8anw8an Posts: 176
    edited 2010-01-03 04:52
    mugur, there is no need to modify the WVC200.

    Fire up a network trace and mess with your camera in a browser. You'll see that the requests to make the camera do things are quite simple. You can then set up your Propeller to send the necessary control messages to the web server in the camera.

    Steve
  • rjo_rjo_ Posts: 1,825
    edited 2010-01-03 05:17
  • Toby SeckshundToby Seckshund Posts: 2,027
    edited 2010-01-03 11:02
    On a lot of the Sony stearable cameras, and tele-conferencing ones, the motors are the three phase sort. Four wires would be true, one per phase and a common. But then they wouldn't have gearboxes, the easy way to test for the three phase sort is to disconect the power and see if the assembly just frees up, to be be completely undriven. They usually hold station by going to the end stops and then coming back to the central position, at switch on, and then being controlled from there.

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    Style and grace : Nil point
  • mugurmugur Posts: 105
    edited 2010-01-03 11:32
    @ Phil: I think i will take a picture to the module where the motors are connected, it is a separate module connected to the webserver board. From what i can tell (not much) it can be a h-bridge. You might be able to figure from the pictures.

    @w8an: thank you, of course i have to figure how i will send the proppeler messages across a wireless network to change my camera possition, maybe an x-bee might be a good step here.

    @Rjo: i am affraid he just used the general term there, i know that the servos use normal DC motors, but those motors never have 4 wires.

    @Toby: you might be right, if Phil cannot figure from the picture, i will try this. The camera make a full tilt and a full pan every time it is started and then position "center" is achived. There are not "end-point" sensors whatsoever, the camera knows when the end of the movement was achived by sensing the stall current of the motors.
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