Results
We were generally pleased with the operation of our system. The relative drawing mode worked fairly well, though some slight "jumps" could be seen on the Etch-A-Sketch when releasing and reapplying pressure on the touchscreen. However, it was fairly easy to draw using relative mode, as drawing circles and diagonal lines, for example (generally fairly hard to do by hand), was made extremely simple with our system.

Our absolute drawing mode tended to have a bit more sensitivity to drawing on the touchscreen as the physical characteristics of the Etch-A-Sketch affected our control software immensely. First of all, the aspect ratio of the touchscreen as compared to the Etch-A-Sketch was not the same, so translating drawing on the touchscreen required a constant multiplicative factor applied to the coordinates read from the touchscreen to adjust for the aspect ratio difference. Also, the sensitivity of the actual knobs on the Etch-A-Sketch impacted the control greatly. During testing, the first Etch-A-Sketch we used broke as one of the knobs was rotated so far that it snapped and ceased to work. As the software was designed for this particular Etch-A-Sketch, when we used a new Etch-A-Sketch for our demo, the movements on the touchscreen did not translate well to the Etch-A-Sketch as the sensitivity on the knobs differed noticeably from our original.