Greetings all; My original config for this had hal connections in all 4 axis like this: loadrt [KINS]KINEMATICS loadrt [EMCMOT]EMCMOT servo yadda + numdio=12 later... net z-pos-cmd joint.2.motor-pos-cmd net z-pos-cmd pid_z.command net z-vel-cmd joint.2.vel-cmd net z-vel-cmd pid_z.command-deriv
But somehow, this joint.2.vel-cmd has a huge high vel spike as it approaches zero velocity, jumping to the same offset in the other polarity, then decays back to where it would intersect a straight line continuation of the original trace, at which point it then continues upwards as if its a position command. And it does it at both polarities of a reversal. This spike is way faster than the z motor can usually move, and results in a z following error at the bottom of a g33.1 move. This is despite a limit3.maxa and maxv setting in series with pid_s that results in a quite leasurely reversal at the bottom of the stroke. Everything else is supposed to just follow the spindle, and its not. In the halscope display, the encoder output is following this restricted reversal quite nicely. There is some pid_s.error showing during these velocity changes of the spindle, but its a gentle curve before and after this velocity spike. So I have to figure out where the wrong signal is getting back to motion from because its all waaay out of time visually now that I have the near problem solved. Has anyone else encountered this, or is it some sort of a bug in motion? The man page for pid says the deriv will be calculated if its not connected, so would I be better off it is disconnected? deadband is set to 0.0001" in that pid, but IMO its being fed bad data by motion. Ideas? I sure could use some. Thanks. 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> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
