caxis.comp status

hello, I check regularly to see your progress, I'd like to help you, but unfortunately I don't have your linux skills, I admire your work.

jpg wrote:

hello, I check regularly to see your progress, I'd like to help you, but unfortunately I don't have your linux skills, I admire your work.

Kind of you, but the reality is that I have no linux skills.  I substitute bloody-minded persistence for actual knowledge.

On a happy note... there was a breakthrough late last night and everything seems to be working rather nicely.  I'll post some details later.

 

Adding some "D" made a huge difference.

I also confirmed that, at least in my config, rotary axis values are in degrees per minute, not seconds.  Needed to bump all the values way up before the C-axis performed properly.

So the basic scheme is:

• Home C-axis first
  • If it isn't homed, a spindle command will result in a following error after stopping the spindle
• C-axis remains enabled until a spindle command is given
  • Can jog, MDI, and G-code the c-axis with no issues.
• Spindle command works both directions, and RPM is +/- 10rpm according to the encoder.
  • Accel/decel are aggressive but smooth
  • Can go M3 to M4 with no pauses or issues
• M5 - spindle stops, then rapids to the last c-axis position prior to engaging the spindle
  • No unwinding, the return move is always <360 degrees
• G-code
  • No problems running a program with both spindle and c-axis moves in it

Remaining issues:

• C-axis PID could still use some tuning but I'm not sure what else to do.
  • It goes where it's supposed to and doesn't get out of control... but I there's too much oscillation during homing or during the automatic return-to-last-position when the spindle is stopped.
  • I've had to set the joint/axis ferror & min_ferror pretty high, otherwise it vomits during homing.
• No way to unlock the servo spindle unless I disable the servo enable-in signal.
  • If I disable the spindle, upon re-enable it rapids back to the prior position
  • Rotating the spindle a few revs by hand trips the following error (simulating a 4-jaw chuck)
  • I need to think about how to disable the f-error when the spindle enable is de-asserted
• Jogging
  • MPG jog required a scale comp to be added to compensate for degrees vs. ipm.  It was way too fine at the standard 0.0001/.001/.01 increments, so I bumped it by 100 for the c-axis.
  • Continuous jogging needs some work.  Reasonable linear jog speeds (10-100ipm) are painfully slow in degrees/min.  Due to my particular config I'm going to have to fiddle a bit.  My jog-speed pot sets the speed for all axis/joint continuous jogs... I may have to split the rotary axis out and scale it.  Not insurmountable.
• Caxis.comp appears to only permit a single instance
  • I tried to set up my sub-spindle as a B-axis tonight but LCNC errored out when created a second caxis.comp instance.
  • 'addf failed' was the error message.  No variation of names= or counts= worked.

Anyone know how to edit a comp to permit multiple instances?

Latest halscope below during a G0 C0, G0 C360 tuning program.
 

Current (working) PID values:

MAX_VEL = 2880
MAX_ACCELERATION = 15000
P = 85
I = 50
D = 2
FF0 = 0
FF1 = 0.144
FF2 = 0.00665
FF3 = 0.000015
maxoutput = 500
deadband = 0.01
MIN_FERROR = 500
FERROR  = 500

Your work is very interesting. You could post all your configuration to work on.

My config is a bit of a mess right now.   I could just zip up the folder, but there are files in there that don't belong... plus hal files that have extraneous comments.

I'll try cleaning things up a bit and post a work-in-progress version later.