Re: machine inaccuracies fixed by software compensation

From: vrsculptor@...

<s>What is need is a way to enter

>a machine compensation table into EMC (sort of like cutter
>compensation) and have it compensate for the inaccuracies based on
>the current X-Y-Z coordinates.
>
>I read about this in an article in American Machinest. Some high end
>controllers are already doing this.

It's in there.

-----RELEASE NOTES snippet-----

New in the 10 August 2000 release:
...
7. Added bidirectional lead screw compensation. Files of compensation
points look like this (these sample comp values are exaggerated):

0.000000 0.000000 -0.001279
0.100000 0.098742 0.051632
0.200000 0.171529 0.194216
0.300000 0.292485 0.291030
0.400000 0.439511 0.367981
0.500000 0.451323 0.493962
0.600000 0.618011 0.618044
0.700000 0.669925 0.735979
0.800000 0.798637 0.787879
0.900000 0.889286 0.927685
1.000000 1.007024 0.959853
...

where the first column is the commanded axis position, the second
column is the measured position (like with a laser) in the forward
direction, and the last column is the measured position in the reverse
direction.

You specify these files in the .ini file for each axis with the
[AXIS_#] COMP_FILE = <filename>, e.g.,

[AXIS_0]
...
COMP_FILE = x.cmp

This entry is optional. If it's not there, no compensation is done.
-----end-----

HTH

Ray