caxis.comp - How to freewheel axis/spindle?

Attached is block diagram showing a spindle orient example. I also attached the hal netlist.PID, limit2, offset, … etc parameters values are not complete, you will need to figure them out as you experiment. 

 

Benb wrote:

Attached is block diagram showing a spindle orient example. I also attached the hal netlist.PID, limit2, offset, … etc parameters values are not complete, you will need to figure them out as you experiment. 


 

@Benb -

Thank you for the comments.

I already have orient working on my subspindle, and generally understand how it works and fits with other LCNC functions.

The problem with trying to combine orient with caxis.comp (attached in the first post) is that the caxis.comp functions are 'in charge' of the spindle motor at all times, except when a spindle-on command is issued.  When the spindle is stopped, C-axis takes over and the PID ferror returns the spindle position to the last position prior to the M3/M4.

I don't know this for a fact, but I think what would happen is a race condition where once the spindle-off signal is triggered, but before orient.comp is engaged, caxis.comp will 'take over' the spindle and return it to the original position.

Meaning orient.comp wouldn't be useful to get the spindle close enough after freewheeling and before re-engaging the c-axis.

If Aciera's unhoming python comp doesn't work, and PCW's doesn't either, I will likely revisit orient.comp.

Benb wrote:

Attached is block diagram showing a spindle orient example. I also attached the hal netlist.PID, limit2, offset, … etc parameters values are not complete, you will need to figure them out as you experiment. 







Hello, could you tell me what OFFSET is used for in your configuration, I'd like to know more about it, on which machine do you use it?
Bravo SPUMCO for your tests on the C axis, it's really a very special configuration, thank you for sharing, I admire your perseverance!

 

@jpg-

What OFFSET are you referring to?

loadrt offset count= 1
addf offset.0.update-output servo-thread
addf offset.0.update-feedback servo-thread
setp offset.0.offset 1
net pid-orient-pos-cmd offset.0.out pid.1.command
...

jpg wrote:

loadrt offset count= 1
addf offset.0.update-output servo-thread
addf offset.0.update-feedback servo-thread
setp offset.0.offset 1
net pid-orient-pos-cmd offset.0.out pid.1.command
...

What you posted is from @Benb's suggestion a few posts earlier, not part of my configuration.

yes, that's right, I wanted to understand what this component brings.

jpg wrote:

yes, that's right, I wanted to understand what this component brings.

Would you mind starting a new thread for tangential questions?

@Aciera -

I tried to use the python comp, but I'm getting an error. Probably related to my installation rather than your file.

lathe@lathe:~$ halcmd loadusr /home/lathe/linuxcnc/configs/LATHE_REV1.713/python/unhome_comp.py
lathe@lathe:~$ /usr/bin/env: ‘python3\r’: No such file or directory
/usr/bin/env: use -[v]S to pass options in shebang lines

Any ideas?