Jon,


> Well, I simply don't understand why this doesn't work.

It quits working when the motors are disabled.  Once you do that, the
wiki method wont track the table position with a stepper machine.

> Now, the screw mapping with backlash may not work at all for manual
> moves.  I believe the code uses the COMMANDED change in direction to
> decide which value to use from the table, so it clearly will not
> compensate correctly for manual moves.

I have already thought about this, but I didn't mention it yet because
I don't people confused anymore than they already are.  However, since
it has been mentioned, It would be a ideal if the screw comp could
continue to follow with the motors disabled.  If if it follows
COMMANDED change of direction as you say, then this could become a
significant problem.  To change all that might be asking a little too
much.


> The "resistance" you sense is historical.  This battle has been fought
> on rec.crafts.metalworking for some 15 years now, and on various
> EMC-related lists for a decade.  Those who have fought the battle know
> the answer, and are tired of the fight.  I'm one of those who believe
> that backlash is a terrible problem, and makes everything else SO much
> harder.  I do practically ALL machining in the climb-milling direction,
> and this alone would be a disaster if I had a lot of backlash.

I am quite happy with the way EMC handles screw comp and lash.  I am
not interested in changing my machine or EMC in these regards.  The
ONLY reasons backlash and screw comp have been mentioned at all in
this thread is because it is the reason I can't feed my scale feedback
into axis.N.motor-pos-fb.  Thats all.

Brian

------------------------------------------------------------------------------
This SF.net email is sponsored by 

Make an app they can't live without
Enter the BlackBerry Developer Challenge
http://p.sf.net/sfu/RIM-dev2dev 
_______________________________________________
Emc-developers mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-developers

Reply via email to