Originally Posted by
Scott_bob
Our CNC control retrofit is now complete!
It's very impressive to see an 8 year old DC Servo Drive CNC machine out perform a brand new Digital AC Servo Drive machine right next to it...
I love the Rubicon (Numeryx) controls automatic feed rate motion algorithms that uses geometric look ahead, and jerk factoring to smooth out the motion.
There is no point going fast if the control cannot maintain accurate positioning and smooth dynamic feed control, speeding up when it can, and slowing when it needs to, automatically. It's really incredible. We set "one" feedrate and the control does the rest. When geometry has sharp "inside corners", feed is reduced, or with small radii. When sharp "outside corners" are detected, feed is increased, as well as when cutting straight. I have simplifed the dynamics here, maybe someday there will be some video posted. Right now we gotta make some parts...
By the way, the feed rate is constantly changing depending on the upcoming geometry, so there would be no point in determining a single feedrate that may represent an ideal "low chatter" frequency.