This software has an "auto-tune" feature which will slowly adjust the parameters and zero-in on a minimum error state. The values it generates vary with the motion parameters I enter. A set of PID for slow motion will be different than one involving faster speeds. I've probably run 4 or 5 different servos through the auto-tune function, and one servo generated values near 8,000. The auto-tune works, but the servos are always "edgy" for lack of a better term. During rapids, they vibrate slightly, resonate, and simply aren't very smooth. I often back off on select values after auto-tuning to smooth it out. As I learn what the parameters do, I am becoming more comfortable with adjusting them manually.
I'm wiring up yet another motor to see how it does. This one is a brushed NEMA34 which is overkill, but I'm curious to see if a more powerful motor will drop the overall error. Ultimately, when I get the mounting figured out, I'm going to test a pair of brushless vs. the brushed jobs that I have been using with a complex g-code.  |