High performance homing

[Karl_T]

Camsoft homing works fine. But it does one axis at a time, making it slow. The Galil card has the abliltiy to home all axis at once. Turns out its a pretty simple Galil program, see below.

There were two tricks here. One of the axis (X) had the home swtich at the minus end of travel, so this axis is temporily switched in direction. Also, Camsoft needs to wait until this program completes. I used a variable named "done" and put Camsoft in a loop until the done variable had the value 3

This is just a tip to share with other camsoft users.

Enjoy

Karl







Camsoft Macro:

'**************************************HOME MACHINE***
[[HOMEMACHINE]] 'called from M110
COMMAND HX 'Halt Jog buttons
COMMAND XQ #AXIS3HM 'execute Galil home routine
:HOMINGLOOP
SLEEP 1.0
COMMAND done=?: RESPONSE \55:IF \55<3 THEN GOTO :HOMINGLOOP 'done is variable in Galil program


Galil .DMC program:

'Below homes 3 axis simultaneously, X axis reversed to home
'done varible used in Camsoft to test for macro complete
#AXIS3HM
done=0
CN,-1 'home in - direction
MO 'turn off motrs for below commands
CE 2 'change encoder direction X axis
MT -1 'change motor direction X axis
SH 'turn motors back on
SP 5000,5000,5000 'set home speed
HM 'home mode
BG ABC 'do these three axis
MC 'wait for motion complete
SP 0,0,0 'speed back to 0
MO 'turn motors off
CE 0 'put X axis back
MT 1 'put X axis back
SH 'turn motor on
done=3 'var to tell camsoft its done
EN

[Al_The_Man]

The method often used on 3 axis, mills etc when setting up automatic homing, is the routine waits for the Z to home first and then the X & Y simultaneously, this usually ensures any tooling is clear first.
Al.

[Karl_T]

If you want to do this with galil, just use the FindEdge, FEZ, command. Put it after the SP command in the galil program and then probably an MC (motion complete) Then the Z would retract first and all three axis finish homing togther.

The galil programming language is a bit cryptic, but very powerful for motion control.

Karl

[Al_The_Man]

Originally Posted by Karl_T The galil programming language is a bit cryptic, but very powerful for motion control. Karl

The one thing I liked about the Acroloop card over the Galil was although Galil has threads you can run simultaneously as did the Acroloop, The ACR also had 8 PLC threads that could be ran for the I/O, timers PLC functions etc.
These had the advantage of running with continuous update, IOW a program is not hung up waiting for a input or timer to complete before continuing as I/O use in a Galil thread.
After I commented on this in the Galil Forum Galil has since implemented a PLC for some controls.
I have usually ended up using a 3rd party PLC that communicates with the Galil I/O.
Al.

[camsoft]

The homing routing is rather clever using advanced techniques. There is a need for both styles. You both have some good points. Al's mention of the Z rising first is typically how it's done on a mill/router. The [Home Master] routine does offer you a choice in a setting near the top of the routine to have Z home separately , prior to XY motion. It should be said that in some cases there may be part mounting and or fixtures that may get in the way. The choice allows Z to come up first then both X and Y to home together with or without finding the index marker. There is even an option to hit the home switch twice. We've used both Acroloop and Galil cards and they both have the power. We have just made it easier for the regular guy to set up a homing routine with out needing to learn the native command languages. We've also implemented a complex internal management of these routines where dozens of PLC style routines can run simultaneously from a central program to manage and over see all events without downloading native commands programs.


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