fully printable optical potentiometer/encoder

Have you ever needed to add a rotational sensor to a robot? They are really expensive and so I tried to make a fully printable optical potentiometer.

Take a look at my Blog to get more informations
http://coolrobotprojects.blogspot.co.at/

The open-Frameworks-Code that generates the Gradient/Encoder-pattern:
https://github.com/thunderbug1/encoder_pattern_generat

The generation of the non radial pattern works but the radial ones donÂ´t.

The thing thatÂ´s still missing is a little paper ring with a gradient on it and which is glued to the rotor.

MK1: (First version)

MK2: (Actual early preview)