I've found max acceleration values are typically 10-20 times the max velocity setting.
JT On 4/12/2014 7:28 AM, Rod Fitzsimmons Frey wrote: > Turns out that when I actually CUT something other than air, using the > loose tolerances (even 0.02) gives me unacceptable faceting. I don't need > *accuracy* per se, but I do need smoothness. > > I don't think I'm trying to operate at outrageous speeds - about > 2500mm/min. Maybe my acceleration is set too low? Or too high? I didn't > give too much thought to the acceleration limits - I didn't know how to > determine it for a servo system. (On stepper systems I just increased it > until I lost steps, then backed off 10% or so -- scientific, hey?) > > > > > On Fri, Apr 11, 2014 at 4:48 PM, Robert Ellenberg <[email protected]> wrote: > >> Hi Rod, >> >> This is actually a good example of why G64 is a bit confusing at first. >> Since you haven't specified a Q word, G64 with a P tolerance by default >> uses the same tolerance for the naive cam detector. What that means is >> that your command here: >> >> G64 P0.05 >> >> Is interpreted by LinuxCNC to mean this: >> >> G64 P0.05 Q0.05 >> >> I'd be willing to bet that if you used this setting instead, it would >> revert to the "ugly" behavior: >> >> G64 P0.05 Q0.0 >> >> -Rob >> >> >> >> >> On Fri, Apr 11, 2014 at 4:19 PM, Rod Fitzsimmons Frey <[email protected] >>> wrote: >>> G0 P0.05 worked like a charm! Thanks Viesturs. I'll have to go read the >>> code to understand the behaviour. >>> >>> >>> On Fri, Apr 11, 2014 at 4:16 PM, Rod Fitzsimmons Frey <[email protected] >>>> wrote: >>>> Perhaps I'm confused about G64? From the docs: >>>> >>>> G64 is just blending and the naive cam detector is not enabled. G64 >> and >>>> G64 P0 tell the planner to sacrifice path following accuracy in order >> to >>>> keep the feed rate up. ... G64 P0 has the same effect as G64 alone >>>> (above), which is necessary for backward compatibility for old G Code >>>> programs. >>>> >>>> I'll try the small value for G64 instead. I'm not concerned about >>>> accuracy in this application - .005" would be fine. >>>> >>>> I'll definitely have a look at the new trajectory planner too! >>>> >>>> >>>> On Fri, Apr 11, 2014 at 3:28 PM, Viesturs Lācis < >>> [email protected]>wrote: >>>>> 2014-04-11 22:15 GMT+03:00 Rod Fitzsimmons Frey <[email protected]>: >>>>> >>>>>> I've set G64 P0, which I think should eliminate motion mode >> concerns? >>>>> >>>>> P0 means that max allowed deviation from defined path in order to >>> maintain >>>>> velocity is equal to as much as total zero, so it really eliminates >> not >>>>> only concerns about motion mode, but also any options to try to >> maintain >>>>> the velocity. Try increasing it to something like 0,02 and see, if it >> is >>>>> better. >>>>> >>>>> I would say that this particular case is a perfect guinea pig for the >>> new >>>>> trajectory planner :) >>>>> >>>>> Viesturs >>>>> >>>>> >> ------------------------------------------------------------------------------ >>>>> Put Bad Developers to Shame >>>>> Dominate Development with Jenkins Continuous Integration >>>>> Continuously Automate Build, Test & Deployment >>>>> Start a new project now. Try Jenkins in the cloud. >>>>> http://p.sf.net/sfu/13600_Cloudbees >>>>> _______________________________________________ >>>>> Emc-users mailing list >>>>> [email protected] >>>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>>>> >>>> >>> >> ------------------------------------------------------------------------------ >>> Put Bad Developers to Shame >>> Dominate Development with Jenkins Continuous Integration >>> Continuously Automate Build, Test & Deployment >>> Start a new project now. Try Jenkins in the cloud. >>> http://p.sf.net/sfu/13600_Cloudbees >>> _______________________________________________ >>> Emc-users mailing list >>> [email protected] >>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >> ------------------------------------------------------------------------------ >> Put Bad Developers to Shame >> Dominate Development with Jenkins Continuous Integration >> Continuously Automate Build, Test & Deployment >> Start a new project now. Try Jenkins in the cloud. >> http://p.sf.net/sfu/13600_Cloudbees >> _______________________________________________ >> Emc-users mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > ------------------------------------------------------------------------------ > Put Bad Developers to Shame > Dominate Development with Jenkins Continuous Integration > Continuously Automate Build, Test & Deployment > Start a new project now. Try Jenkins in the cloud. > http://p.sf.net/sfu/13600_Cloudbees > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Put Bad Developers to Shame Dominate Development with Jenkins Continuous Integration Continuously Automate Build, Test & Deployment Start a new project now. Try Jenkins in the cloud. http://p.sf.net/sfu/13600_Cloudbees _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
