On Tuesday 01 December 2020 16:43:49 andy pugh wrote: > On Tue, 1 Dec 2020 at 21:40, Chris Albertson <[email protected]> wrote: > > The next step is to see why PID is not very good at this. It is > > reactive and can't plan ahead. For example, it can't say "I am > > only a few floors away from my target I'd better apply the brakes. > > That's exactly what the D term _can_ do.
And, if I stay below around 80% on the pwm, I have it working fairly well. TB fine tuned when I manage to get it on the bs-1 along with a home switch. FF1=1, FF2=.25, Pgain=50000, Dgain=2.5 and as long as I stay below about 200 degrees (with an encoder scale of 5000) a minute, good smooth stops, try 300 degrees a minute and it jumps up in the air and might kill the psu getting stopped. And no amount of extra Dgain fixes that, I think its windup as it cruises longer after I release the key. Dgain also restricts its top speed, to be expected I think. Thank you Andy. 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 [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
