On Thursday 10 September 2015 11:47:04 Tom Easterday wrote: > > On Sep 10, 2015, at 11:34 AM, Gene Heskett <[email protected]> > > wrote: I have not encountered anything even remotely resembling that > > on my lathe with its 200 edge/turn A/B/Z homemade encoder. > > > > If it was jerking at 50 revs, thats more than 1 second per turn and > > the speed changes would be extremely visible. Thats not saying mine > > is dead smooth at 50 revs, but Z tracks its speed variations quite > > well, making a lot of racket from the Z stepper racheting its speed > > up and down in exact time with the spindle speed. > > You cannot see or really even feel any speed changes or vibrations in > the spindle but if if they are small enough I don’t think you would. > I am only running a servo thread at 1ms since I have the Mesa cards. > > > Gotta be something else going on. > > > > An accidentally wide deadband setting in the Z's PID? > > These are steppers, no PIDs set up. > > > addf's in the hal file waaaayyy out of fall thru sequence in one > > servo-thread cycle? All that stuff should be addf'd in the order of > > the signal path thru each logic function. But I'm sure you knew > > that, Tom. > > Only vaguely aware. I do recall having an issue with that when I > first set up my Emco mill years ago. Here is the top section of my > hal file, is there anything glaringly wrong? > > loadrt trivkins > loadrt [EMCMOT]EMCMOT servo_period_nsec=[EMCMOT]SERVO_PERIOD > num_joints=[TRAJ]AXES > loadrt hostmot2 > loadrt hm2_pci config=" num_encoders=1 num_pwmgens=0 num_stepgens=3 > sserial_port_0=00xxxx" > setp hm2_5i25.0.watchdog.timeout_ns 5000000 > loadrt comp count=2 > loadrt timedelay count=2 > loadrt and2 count=5 > loadrt not count=5 > loadrt xor2 count=5 > loadrt or2 count=1 > loadrt debounce cfg=1,2 > loadrt near > loadrt scale count=2 > loadrt lowpass count=2 > loadrt abs > loadusr -W toolerator3000 > > addf hm2_5i25.0.read servo-thread > addf motion-command-handler servo-thread > addf motion-controller servo-thread > addf comp.0 servo-thread > addf comp.1 servo-thread > addf timedelay.0 servo-thread > addf timedelay.1 servo-thread > addf and2.0 servo-thread > addf and2.1 servo-thread > addf and2.2 servo-thread > addf and2.3 servo-thread > addf and2.4 servo-thread > addf not.0 servo-thread > addf not.1 servo-thread > addf not.2 servo-thread > addf not.3 servo-thread > addf not.4 servo-thread > addf xor2.0 servo-thread > addf xor2.1 servo-thread > addf xor2.2 servo-thread > addf xor2.3 servo-thread > addf xor2.4 servo-thread > addf or2.0 servo-thread > addf debounce.1 servo-thread > addf near.0 servo-thread > addf scale.0 servo-thread > addf scale.1 servo-thread > addf lowpass.0 servo-thread > addf lowpass.1 servo-thread > addf abs.0 servo-thread > addf hm2_5i25.0.write servo-thread > > > Way to low a pid.s.Pgain because it oscillated because of the above > > lag? > > Again, no pids…
Humm. pncconf sets up a pid for everything that moves, so you must have a hand carved .hal file. But I haven't piddled with mine for the xz as they have so far Just Worked(TM). But I am in the process of redoing the spindles signal paths in my hal, so the pid.s is essentialy zeroed out except for unity gain in FF0=1.000 ATM, and I am finding even that to be too high when I am trying for unity gain after that pid.s module. > Thanks Gene, You are welcome, Tom. Hopefully there might be a clue in my ramblings. PID's seem to be a great way to track and correct errors before they get too big, and that might be a solution for you. YMMV of course. > -Tom 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> ------------------------------------------------------------------------------ Monitor Your Dynamic Infrastructure at Any Scale With Datadog! Get real-time metrics from all of your servers, apps and tools in one place. SourceForge users - Click here to start your Free Trial of Datadog now! http://pubads.g.doubleclick.net/gampad/clk?id=241902991&iu=/4140 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
