On Thursday 23 July 2020 07:53:45 andy pugh wrote: > On Thu, 23 Jul 2020 at 12:47, Nicklas SB Karlsson > > <nicklas.karlsso...@gmail.com> wrote: > > > I wonder what effect could be had by rate-limiting the PID output > > > to the motors? > > > > Integrator should ideally have anti-windup. > > Anti-windup is a little different. > > I was actually thinking about experimenting with a limit3 HAL > component between the PID and the PWM.
But that s/b bypassable for rigid tapping as it will increase the following error. Put it in front of the PID. I use it there to profile the spindle turnaround rates to something the Z can follow w/o throwing a Z following error. Its more complex than that in the hal file, but thats the general idea. And I've not had good results while driving a vfd. Needs more thought there but a 40 lb chuck's inertia overrules most of my efforts. The PMDC motors respond much better to that sort of control massaging. Faster is the keyword I think. My thinking was that of a sine-squared control waveform with the peak accel at zero speed, therefore matching a steppers ability to keep up better. Idea was stolen from one of the old analog tv VITS. That kit of signals allowed one to accurately tune a tv transmitter for optimum bandwidth while the girls were watching Days of our lives. Or whatever. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
