Another "what do I need" thread. Vmc retrofit
Please Log in or Create an account to join the conversation.
It seems to be working now
![:) :)](/media/kunena/emoticons/smile.png)
Please Log in or Create an account to join the conversation.
![;) ;)](/media/kunena/emoticons/wink.png)
The computer I have there for cad/cam and now for reading lots of pdf's was bluescreening like crazy today
![:angry: :angry:](/media/kunena/emoticons/angry.png)
I did almost go mad when I was trying to tune the PID settings today.. Got it quite good, forgot to save and restarted Linuxcnc
![:huh: :huh:](/media/kunena/emoticons/wassat.png)
![:( :(](/media/kunena/emoticons/sad.png)
Max velocity is set to 10m/min
Acceleration is set to 1000mm/s²
I got those numbers from the machine manual.
This is where I left it anyway. If I read the graph correctly then the axis is off by ~0.18mm under acceleration. Suggestions are appreciated
![:dry: :dry:](/media/kunena/emoticons/ermm.png)
I did get homing to work though.
And some more info on the tool changer:
-It takes 8 seconds for the carousel to do a full revolution.
-The carousel can be quite off position and still be "pushed" to the correct spot by the lock pin
-The hydraulic pump that activates the drawbar has one way valve in series so the pump only need to run until the "drawbar is fully extended" sensor senses that. Then a electronic valve releases the pressure when you want to retract the drawbar.
- Z needs to be at +10 from its home switch to clear tools in the carousel
Please Log in or Create an account to join the conversation.
this sample is for 3 axis machine with joint 0,1,2
first need to put in your ini file:
[POSTGUI_PARAMS]
# this is the minimum acceleration limit, your machine is set this in startup
MINIMUM_ACCELERATION = 350
# this is the limit of maximum acceleration
MAXIMUM_ACCELERATION = 700
and add this to postgui halfile,
or make a new file named "postgui_halfile.hal" :
loadrt wcomp count=1
loadrt mux4 count=1
addf wcomp.0 servo-thread
addf mux4.0 servo-thread
setp wcomp.0.min [POSTGUI_PARAMS]MINIMUM_ACCELERATION
setp wcomp.0.max [POSTGUI_PARAMS]MAXIMUM_ACCELERATION
net accel-out-mux-sel0 mux4.0.sel0 <= wcomp.0.under
net accel-out-mux-sel1 mux4.0.sel1 <= wcomp.0.over
net m68-e0-q wcomp.0.in <= mux4.0.in0 <= motion.analog-out-00
setp mux4.0.in1 [POSTGUI_PARAMS]MINIMUM_ACCELERATION
setp mux4.0.in2 [POSTGUI_PARAMS]MAXIMUM_ACCELERATION
setp mux4.0.in3 [POSTGUI_PARAMS]MAXIMUM_ACCELERATION
net accel-out-mux ini.0.max_acceleration <= ini.1.max_acceleration <= ini.2.max_acceleration <= mux4.0.out
last thing is check your ini file HAL section POSTGUI_HALFILE = postgui_halfile.hal
now program "M68 E0 Q###"
Q number is the acceleration
Please Log in or Create an account to join the conversation.
a program is not running
The per-axis max_velocity and max_acceleration pins are sampled when the machine is on and the motion_state is free (homing or jogging) but are not sampled when in a program is running (auto mode) or in mdi mode. Consequently, changing the pin values when a program is running will not have effect until the program is stopped and the motion_state is again free.
Ref: (2.7) www.linuxcnc.org/docs/2.7/html/config/em...l.html#_ini_settings
The pins may still be useful for changing the max_acceleration values without restarting, example, in
a terminal:
$ sim_pin ini.0.max_acceleration ini.1.max_acceleration
Please Log in or Create an account to join the conversation.
![:) :)](/media/kunena/emoticons/smile.png)
Do anyone have any suggestions on what to change to further decrease the following error? If I increase FF2 then the initial "peak" decreases but it overshoots like crazy just after. (the big dip on the graph)
![:pinch: :pinch:](/media/kunena/emoticons/pinch.png)
Please Log in or Create an account to join the conversation.
Do anyone have any suggestions on what to change to further decrease the following error?
You could try a faster servo-thread rate.
You might also find some of the discussion here interesting:
thread.gmane.org/gmane.linux.distributions.emc.devel/8816
Please Log in or Create an account to join the conversation.
I did get homing to work though.
To save valuable seconds you can give X and Y the same home-sequence number.
Please Log in or Create an account to join the conversation.
How much following error is acceptable?
Nice trick to home both X and Y at the same time
![:laugh: :laugh:](/media/kunena/emoticons/laughing.png)
Please Log in or Create an account to join the conversation.
How much should I increase it? 20%?
I was thinking that you could try doubling the rate, ie 2kHz servo-thread not 1kHz.
PCW has reported that that helps.
Also try plotting position-cmd and position-fb, see if it really is as bad as f-error suggests, the email discussion suggested that f-error calcs might be a bit wrong.
Please Log in or Create an account to join the conversation.