Cliff:
I've been thinking on and researching this subject in my spare time this week. I have been reminded of something I read about servo motors and there operation several years ago. I went back to that book (my wife refers to it as my NERD book) and read that section. Maybe we are looking at the angular sensor issue all wrong. Why not use precision potentiometers in lieu of optic encoders? It appears that they my be both more accurate and more economical. I have emailed
Novotechnik for pricing. Their P6500 has a resolution of 0.007 degrees and linearity of +/- 0.05%. The best part would be that there would be no need to count "clicks". This would seem to reduce the overhead of the electronics. If you added an A/D converter or connected the fours pots to a microcontroller (ex. OOPIC) there would be even less overhead on the computer. Maybe I'm making this sound too easy. What do you all think?