On Oct 15, 2011, at 9:46 PM, Peter C. Wallace wrote: > Setting steplen or stepspace longer can only make the stepgens maximum > velocity _lower_ not higher, so that cannot help (unless you have an > interface > speed problem but this would not show up as a following error but rather as > missed steps) > > Following errors in a pure open loop step generator system mean that > something > is limiting the driver code from setting a high enough velocity in the > step generator hardware. Maybe something has been omitted causing a scale > error so you have a un-obvious velocity limit.
Peter (whom I am working with) found the problem (see below), which is essentially an instance of what you point out above, Peter. So is this a bug or a feature? Tom On Oct 15, 2011, at 10:50 PM, Peter Jensen wrote: > Tom, > > The problem was the Y1 axis max velocity was set at 39, but the max jog > speed was set to 58. So, if you set the jog speed over 39, EMC did a very > stupid thing: it commanded the drive to move at 58 (or whatever you set it > to), but also prevented the axis from moving faster than 39. Result: an ever > increasing following error. I assume this is a left hand not knowing what > the right hand is doing thing: I think EMC was happy to move at 58 ipm, but > the mesa card was smart enough to not go over 39 for this axis. They need to > get their stories straight ;-) > > This is why you would never see the problem unless the jog velocity was over > 39 = 2340ipm. > > Setting the Y1 axis max velocity up to the same number as the max jog speed > resolved the problem. > > That's one down... only remaining problem is the granite drive still faults. > > Cheers, > > -Peter ------------------------------------------------------------------------------ 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
