On Sun, 16 Oct 2011, Tom Easterday wrote: > Date: Sun, 16 Oct 2011 20:43:21 -0400 > From: Tom Easterday <tom-...@bgp.nu> > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Subject: Re: [Emc-users] config without encoders > > > On Oct 16, 2011, at 7:41 PM, Peter C. Wallace wrote: > >>>> >>> Peter, >>> >>> Is there any reason not to open up the stepgen limits on accel and >>> velocity so they cannot possibly be a limiting factor? Make them >>> 1.0EE6 or so? >>> >>> Dave >> >> Yes, in some very specific situations, the current stepgen driver has >> some pathologies when its has unlimited acceleration and velocity limits >> I believe the problems are triggered by differences in the hardware clock and >> the computers thread rate and also by large amounts of jitter on the servo >> thread. These problems seem to go away when reasonable values of stepgen >> maxaccel and maxvel are used (I think its most likely that maxaccell is the >> sensitive parameter) > > You are talking about: > setp hm2_7i43.0.stepgen.01.maxaccel [AXIS_1]MAX_ACCELERATION > setp hm2_7i43.0.stepgen.01.maxvel [AXIS_1]MAX_VELOCITY > > Yes? What do you consider reasonable? We currently have MAX_ACCELERATION = > 120 but have tried values down to about 20-30.
Its not a fixed value: Reasonable is perhaps 20 % greater than the machine (EMCs limits) so there is always headroom for the hardware If these numbers are less than the machine (EMCs) limits you will get following errors > > Tom > ------------------------------------------------------------------------------ > All the data continuously generated in your IT infrastructure contains a > definitive record of customers, application performance, security > threats, fraudulent activity and more. Splunk takes this data and makes > sense of it. Business sense. IT sense. Common sense. > http://p.sf.net/sfu/splunk-d2d-oct > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > 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. ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2d-oct _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
