Hi Dewey,
A FIR low pass works better than reducing the acceleration. The problem
with just reducing acceleration is that it affects the MPG response over
the whole speed range. If you try to move fast the machine responds
slowly. A FIR filter effectively sets the minimum time to make a jog
move. Say you have your MPG set 1mm per click. Without filtering if you
move the MPG 1 click the machine will move 1mm as fast as it can. Now if
you add a 150ms filter the machine will move 1mm in about 150ms or
400mm/min max speed. If you quickly move the MPG 2 clicks the move will
be at about 800mm/min. At high speeds the axis acceleration limits take
over and the filter has negligible effect.
Les
For versions LinuxCNC 2.8 and greater, pins are
provided to limit acceleration for MPG (wheel)
jog inputs:
#----------------------------------------------------
$ man motion
...
axis.L.jog-accel-fraction IN FLOAT
Sets acceleration for wheel jogging to a
fraction of the ini max_acceleration for the
axis. Values greater than 1 or less than
zero are ignored.
...
joint.N.jog-accel-fraction IN FLOAT
Sets acceleration for wheel jogging to a
fraction of the ini max_acceleration for the
joint. Values greater than 1 or less than
zero are ignored.
...
#----------------------------------------------------
These pins may be used with or without lowpass
filters connected to *.jog-counts wheel jog pins
https://github.com/LinuxCNC/linuxcnc/commit/d69b15cfe1
_______________________________________________
Emc-developers mailing list
Emc-developers@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-developers
