On Sat, Dec 22, 2012 at 02:27:39PM -0500, Stephen Dubovsky wrote: > Sorry Peter, I have respect for you (great products!) but I *COMPLETELY* > disagree w/ this. I have my masters degree in power electronics and > control and have lots of experience in on and off road traction drives (aka > electric vehicles.) > > P first > I next
Stephen, I have tuned somewhere between several and quite a few real-world servo machines running linuxcnc. Some have been torque mode (raw H bridge) type configurations, but most have been industrial velocity mode servo systems as found on the usual retrofit candidate. I have a couple like this in my own shop. One is a powerful high-acceleration machine. I have always used something very much like what PCW described, and I especially agree with his advice about disabling I gain until the very end when following error is already small and FF is contributing most of the output. With I gain in early tuning, the effects of the other parameters you are manipulating are totally and utterly disguised. I don't understand all of what you said about analysis and plotting etc.; I have tuned these systems using the information we have available today: mostly, commanded velocity and position, and actual realtime position error. Perhaps you have different kinds of feedback, analysis, or reporting to use while tuning the systems in your field of expertise. But for linuxcnc users tuning machine tools, I think PCW's advice is good and is based in lots of experience that matches mine. Chris ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
