[0: Requirements]

Before performing the steps presented here, please install the robotreality software as described on the page Download, Building and Installation.
You will have to connect the [[Sceneview Camera|sceneview camera you have built] to the PC running the sceneview software. For a first test any USB camera (640x480, 30Hz) will work as well.

This page will guide you through the process of setting up and running the robotreality sceneview software.

[1: Preperations]

In order to complete the following steps you should have finished construction of the motion capture helmet hardware.
Download, print out and fixate the calibration pattern on the projection surface.

Open nvidia-settings (or similar) and configure your second screen (=projector) to be:
  • Twinview
  • 848x480 @60Hz
  • positioned in absolute coordinates at position +0,+45 (this will effectively remove the window decorations)

[2: Calibrate]

The robotreality sceneview program includes a tool for projector calibration. Please run robotreality_sceneview and move the window to the upper left corner of your screen.

All settings can be accessed/configured using key and mouse-presses:

'x' = exit application
'1' = select red channel for calibration
'2' = select green channel for calibration
'3' = select blue channel for calibration
'd' = toggle between 1-dim distortion correction and 3-dim distortion correction (recommended)

In order to calibrate:
  1. let the projector run for at least 5min before performing any calibration/focus adjustments
  2. adjust the image position (pan, tilt & zoom) using the adjustable screws/lens on the helmet setup
  3. adjust the focus on the projector
  4. swtich off the light (the blue markers are hard to see)

Now we will run the calibration. Even though the calibration is presented as a straight flow from blue to red you can always jump/go back to any desired step by using the associated keypresses.
In order to calibrate the projection screen activate the "PROJECTION" window and right click at the center position of the Firefly Lens. This will place a white crosshatch where we will later on project the "black spot".

Now press '3' on your keyboard. You will now see 48 blue crosshatches next to their id.
You can drag and move the crosshatches using the mouse: Place the mousepointer close to the crosshatch you want to move, press and hold the left mousebutton and release it when you reached the target point.
The following picture shows the view on the projection screen during the calibration: crosshatches 0-10 have been placed correctly, the others are uninitialized.

Finish the blue channel calibration and place all 48 blue crosshatches on the grid. Take your time, the more accurate you place them, the better the final result!

Now press '2', this will show the green crosshatches as well. Move them to the right locations. You might notice that once the green crosshatches are correctly placed it appears that they change their color from green to cyan. This can help you placing the crosshatches. After placing all markers your picture will look like this:

Now press '1', this will show the red crosshatches as well. Continue placing the red crosshatches on the grid. You might notice a appearent colorchange to white when placed on the right spot. It is important that the crosshatches turn white to some degree, the id numbers might look blurry (thats ok). Afterwards your projection looks like this:

Now you can move the window entitled "CAM" to the upper left screen corner. The view on the projection screen should be undistorted and straight like shown on the left side:

The right image shows the "pre-warped" image as it looks like on your normal tft screen.When projected, this artificial (anti)distortion is then "corrected" by the lens and beamers offset location to form a rectangular, chromatic abberation corrected image on the projection surface.

When you are done press 'x' and the application will terminate. The current calibration config file is written to /tmp/cfg.headprojector.on_quit. Please copy this file to a safe directory.