Peter; I am attempting to setup a new control chain for my lathes spindle. One that will be a bunch simpler in the hal file.
The 5i25's pwmgen actually has a duty cycle range from about 1% to 98% of so. So if I am using a scale factor there, to tame the axis big jumps when clicking on the + and - buttons, it seems to me that the value I apply to a limit2 in front of your 5i25 pwmgen should also be scaled up by this same scale factor. Right? So if I am using a scale of 2000, then that limit should be scaled up to preserve the duty cycle range while at the same time assuring it never gets to 100%. In fact if I load both of the limits by just inverting the sign of the ini's S_SCALE for the - limit of that limit2, its should then automatically track. Given that I have established that but not made it hal code yet, then it seems like I should be able to scale the pid.s.FF0 such that an s100m3 gets me about 100 rpm, and an s1200m3 gets me just about full scale. The gearing is such that wide open is about 1250 revs in high backgear. But with the encoder feedback applied, the pid.s.error is a huge - factor that is about the pid.s.command value inverted. Any Pgain slows it a huge amount, with Pgain = 0.0125 slowing it like a divide by 5. So, what is the trick to get it to run at the approximately correct speed at s100 and s1000, with a pid.s.error floating at about a noisy 0.000 for both speeds? I am trimming the low speed with the pid.s.bias, which I do based on the requested direction in my .hal file. Figures in the range of 0.026 plus and minus are fairly close. 15 rpm seems doable but variable. Right now I seem to be in a tunnel, and can't even discern the headlight of an oncoming train. Not even sure there a train running on this track! Playing with pid.s.FF0 seems to hold some promise, but the results don't fit the data I am getting. So if you have a spare bone, throw it my way please. Thanks Peter. 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 Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
