On Mon, Dec 10, 2012 at 5:10 AM, andy pugh <[email protected]> wrote:
> > Is a sine-wave the correct input signal? > When I spent my working day creating frequency response curves we > typically used white-noise excitation. > > I've always had pretty good luck with the Schroeder multisine, which is a sine sweep that keeps the amplitude constant. I suppose that's not all that important with a machine tool. Not sure I'd really want to hit my system with white noise, a lot of that's pretty unimportant to a machine tool anyway. I can never remember the actual transfer function of a PID, and I'm too lazy to work it out right now. A lot of low order systems would never go into oscillation with a simple feedback gain, but obviously you are adding dynamics with the PID and that changes things. I was never very good at tuning by looking at a bode plot. Root locus always made more sense to me. Eric ------------------------------------------------------------------------------ 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-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
