Hey you should look into a Prototype This episode, one of the characters, zoz implements glyph tracking, a webcam, two rc servos, and a labyrinth/ball maze simialer to yours, and he made a program that detects the angle to the horizon of the glyph (a little piece of paper) and that orientation is transfered into x,y coordinates, which is transmuted into each servo. Its really quite cool, and it was just a test to make sure they were working.