On Tue, 6 Oct 2015, Gene Heskett wrote: > The above settings seem to have brought it under control, but one > question, 2 actually, remain. > > 1. MAX_OUTPUT was set for 32.5 by PNCconf, but looking at it with a > halmeter it appeared to be setting a restriction on how much "catchup" > was available, so I had raised that to 50 some months ago, and tonight I > raised it to 100, which seemed to alleviate the Z coasting far enough > after it had hit the home switch, to hit the top of the slot in the post > with the nut holder brackets leg about 2mm above the switch. With > MAX_OUTOUT at 100, and some pretty aggressive accels that I may raise > some more, it stops a few thou short of banging the top of the slot in > the post. I came back in with it working, but the FERROR at 0.0001 is a > nothing add, because MIN_FERROR is still 1.0. And it was tripping off > at that 1.0 & very small change.
Umm... not sure if backwards FERROR limits make any kind of sense... I would set the PIDs maxoutput to 0 (no limit) limiting the PIDs output should not be needed I would set MIN_FERROR to say .0005 inch and FERROR to say .002 to start if you get following errors with these settings something is wrong in the tuning or stepgen headroom. _any_ significant deviation from the commanded path indicate some kind of problem in the stepgen setup, In my test setup here, properly tuned the stepgen output will stay withn 50 uinch of command with 1200 IPM and 3G accel. (not that any mechanics could) This is using the DPLL so read jitter is reduced to about 50 ns but at your speeds, read jitter should only cause say 100 uinch of position uncertainty (assuming worst case 100 usec at 60 IPM) > > Was this correct for a millimeter machine? > Yes, PID tuning does not change from mm to inch as long as the input and output units are commensurate (and they are in the stepgen case: PID input is position error in machine units, PID output is a velocity command in machine units per second) Where tuning changes is on things like analog velocity mode servos wherw the PID output is scaled in volts. I encourage people to _not_ do this but rather scale the analog output in machine units per second so the PID tuning parameters are independent of machine units. > Thanks Peter, I can go back to checking why some hal code isn't running a > transistor which is supposed to be running a bigger relay, turning a > vacuum cleaner on and off so it sucks up the sawdust I about to make a > few bushels of. I made a centrifical separator out of PVC stuff so as > to dump the majority of the sawdust into a 5 gallon bucket on its way to > a shop-vac "Bucket Max". I've cleaned up the floor a couple times awith > it and it seems to be doing a decent job of separating the sawdust into > dust & semi-clean air. Makes a $30 HEPA filter last a lot longer. > > Thats tied to the flood checkbox, while the mist button is tied to a > motor via a DPDT relay to flip the jigs locator bar and touch points in > and out of the way. > > So tomorrow I go pay the guy for his computer. It is going to do the job > I believe. When he found out who I was, and what I wanted to do with > it, he refused to take my money before I found out if it would work. > Now I know it will. ;-) I like doing business with folks who actually > know something. > > Thanks Peter. >> >> Peter Wallace >> Mesa Electronics >> > 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) > Genes Web page <http://geneslinuxbox.net:6309/gene> > > ------------------------------------------------------------------------------ > Full-scale, agent-less Infrastructure Monitoring from a single dashboard > Integrate with 40+ ManageEngine ITSM Solutions for complete visibility > Physical-Virtual-Cloud Infrastructure monitoring from one console > Real user monitoring with APM Insights and performance trend reports > Learn More http://pubads.g.doubleclick.net/gampad/clk?id=247754911&iu=/4140 > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------------ Full-scale, agent-less Infrastructure Monitoring from a single dashboard Integrate with 40+ ManageEngine ITSM Solutions for complete visibility Physical-Virtual-Cloud Infrastructure monitoring from one console Real user monitoring with APM Insights and performance trend reports Learn More http://pubads.g.doubleclick.net/gampad/clk?id=247754911&iu=/4140 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
