we have had some severe Linkbot Spazzyness issues. Approximately once per rotation it will speed up for a moment, then go back to normal. It is really annoying and the students are getting frustrated. We are working on PC’s with the PyLinkbot library for python 3.4.3 and have noticed the issue starting around Linkbot Labs 0.7.8 through the current version (1.0.3). We are hoping you can help us fix this in time for the school year.
I figured it out, thanks to the Troubleshooting Wiki:
My robot’s motors seem jerky when trying to move at a constant velocity
Robots come pre-calibrated from the factory, but they may sometimes need recalibration. To recalibrate the constant velocity control, hold down the “A” button on your robot for two seconds while it is on. The motors will begin to rotate for 5 seconds as the robot recalibrates itself.