VR Tracker Update

Afternoon developers!

I recently got in contact with Jules to set up my own VR Tracker system, and was able to replicate it with a few changes to the code that has been available on this blog. VrTrackerUpdate contains the updated code, as well as a text file with an explanation of how it works (see below). Reach out for further explanation if needed, and look out for more posts with further updates to the platform.

– Sawyer Warden

 

 

Changes made as of 6/1/2016

This updated .zip archive has a few alterations to Jules Thuillier’s original VR Tracker code. These changes worked for me as I went through the process
of setting up my tracking rig.

The set-up is as follows
-3 NodeMCU ESP8266-12E are utilized, 1 for each modified Pixy-cam and 1 acting as a Tag
-Each camera’s ESP runs vrtracker_websocketV2.ino, and the Tag’s ESP runs vrtracker_tagV2.ino
-The Gateway (a python websocket server) runs on a pc or RPi (though, at the moment the server uses open-cv and this can be slow on RPi)
-Run the server with vrtracker.py using Python2
-SimpleWebsocketClient plugin for Chrome (or similar) connects to server, allowing for calibration of cameras and initiation of tracking
-Unity app with the VrTracker Unity package imported for WebSocketSharp – using the updated VrTrackerUser.cs
(simply has System.IO imported,this may not matter for you but I needed it for android
to work)
The ESP code and python Gateway have comments for personalizing wifi information. The unity script values must also be changed accordingly.

Calibration Steps
-Start server (at the moment, it seems that the ESP’s can’t reconnect to the server. A fresh start is needed any time an error occurs. This
only seems to happen when the cameras are calibrated, and detect IR before Unity app is started/the tag is declared-see below)
-Turn on all ESP’s, make sure cameras can’t detect any ambient IR
-Connect to server with client plugin on chrome
-Send “calibration”, then “enter”
-type (don’t send) “calib:” followed by coordinates of known, real world points
(i.e. “calib:0-0-0” for the origin, in X-Y-Z. Note that the orientation of your known-point coordinate system can
change depending on if the cameras are in front of you or off to the side, or otherwise)
-Be ready to flash the IR at the location of the known point. Send the message from above, then flash the IR. The client should output
2D coordinates collected by each camera
-Repeat this process for each known point (at least 4). Then send “exit” to close the calibration sequence. 3D coordinates of the cameras
will be displayed after calculation.

After the cameras are calibrated, connect Unity and send “user-#” from the client, replacing “#” with whatever number the Tag-ESP was
assigned by the Gateway server (i.e. if you connected the tag first after starting the server, send “user-1”). The system should begin
tracking.

If an error occurs between calibration and play (maybe due to ambient IR, or exposing IR beacon before tag is identified) simply power off/disconnect all parts, and start up again in proper sequence. The camera preferences will load, unity will connect (send “user-#” to ID the Tag), then expose the cameras to the IR beacon

6 Comments

  1. Michael van Eeden

    Hi Sawyer, Jules,
    Thanks a lot for sharing this great setup with us! I am trying to set it up and have most of the parts in place.

    do you maybe have a schematic for the tag? And where did you get the nice dome tag from, Jules? 🙂

    • JulesThuillier

      Hi Michael !

      Concerning the Tag I’m sorry I don’t have schematics to give you yet. A friend of mine will start working on it very soon.
      Here is a quick schematic I’ve done on the whiteboard just for you XD

      Whiteboard Tag Circuit

      Concerning the dome, it’s simply 3D printed with transparent ABS. I wanted to send you the STL file, but it appears that I deleted it by mistake :/ I’ll upload the next one as soon as it is out !

      • Michael van Eeden

        Thanx a lot! I already suspected i would need to use a transistor for the ir led. great! Looking forward to the new Gateway software.

        • JulesThuillier

          You’re welcome ! I’ll keep you updated on the Blog, we are working very hard on the architecture of the Software at the moment 🙂

      • Nate Pinion

        Do you have a part number on the IR LEDs that you used?

        I have tried both (VSMY3940X01-GS08CT-ND) and (VSMY1940X01CT-ND)and neither one has a strong enough output to be seen more than 2’~3′ from the camera.

        http://www.vishay.com/docs/84214/vsmy1940x01.pdf
        http://www.vishay.com/docs/84220/vsmy3940x01.pdf

        • JulesThuillier

          Hi Nate,

          I used pretty much the same LED.
          I see two different problems you might have :
          1. You are trying to see the LED directly with the camera, and as the LED is very small, it quickly gets under the size of a pixel. You should use a diffuser to enlarge the size of the blob.
          2. You haven’t set then Pixy luminosity properly. Please check the blog, there is a video about that (Installation).

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