Hi, Dave, we are tracking a solar dish with closed loop eyes +/- 0.004 degrees and are using Memsic accelerometers for position feedback. The recent MEMS sensor altitude and azimuth (plus time) data are stored for tracking error detection (for ground torching fire safety) and for dish approximate open loop tracking during cloudy weather. If the data are not recent because the solar declination has changed then our solar position algorithm takes over command of safety protocols. Basic Stamp was too expensive for global technical transfer so we are migrating over to PIC.

http://www.harbornet.com/sunflower/pvdish.html