On Sunday 13 May 2007, Jack Ensor wrote: >Thanks for the suggestion of trying 0.0 backlash. That cut the error >down significantly. Why should that make such a difference? Backlash >compensation error shouldn't be cumulative , should it? > I am now getting from .0101 to .0002 variance. Still more than I would >like to see. > >Jack Ensor > The one item that sorta jumped at me in the .ini you posted was that the default acceleration in the [TRAJ] section was quite high. Backlash motions are finally done under the same accel settings now whereas before they were pumped out as fast as the generator could make them. So even at a 15 setting, that may be too much. I'd try pulling that down to a few percent less than the maximum of each axis just so the axis had some headroom to keep up.
I could also be full of it. :) >Chris Radek wrote: >>On Sun, May 13, 2007 at 09:57:08AM -0400, Jack Ensor wrote: >>>However when I run axis.ngc, the ending x and y positions are at >>>variance from the commanded positions and each time I run the program >>>(after first homing), I get different variances. I calculated the >>>variances by subtracting the actual position from the commanded position >>>and x can vary from -.148 to +.009, while y can vary from .063 to .008. >> >>What version of EMC2 are you using (Help/About will tell you) >> >>Have you tried without backlash compensation (BACKLASH=0.0)? >> >>Chris > >------------------------------------------------------------------------- >This SF.net email is sponsored by DB2 Express >Download DB2 Express C - the FREE version of DB2 express and take >control of your XML. No limits. Just data. Click to get it now. >http://sourceforge.net/powerbar/db2/ >_______________________________________________ >Emc-users mailing list >Emc-users@lists.sourceforge.net >https://lists.sourceforge.net/lists/listinfo/emc-users -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) I must Create a System, or be enslav'd by another Man's; I will not Reason and Compare; my business is to Create. -- William Blake, "Jerusalem" ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
