Servo Tuning FF

Hi Andy - just read this and it is a good starting point. I am totally new to EMC2 and feeling my way around. Please tell me just where these 'FF' values are set and how to get there. I am using Mesa 7i43 (small) with 7i33.
Thanx

centaur wrote:

Please tell me just where these 'FF' values are set and how to get there. I am using Mesa 7i43 (small) with 7i33.

They are set in the HAL file, in exactly the same was as the PGain and IGain.
The actual values are probably read into the HAL file from the INI file, but putting them in the INI file will achieve nothing without a reference and a setp statement in the INI file.

You probably need to understand a bit about HAL pins and parameters.
linuxcnc.org/docview/2.5/html/hal/basic_hal.html

The pins and parameters of the PID component are described here:
linuxcnc.org/docview/2.5/html/man/man9/pid.9.html

Hi all,

verry good thread ...

to make SIMulated and optimicing my PID i have on my PC (office) the servo_sim.ini ...

what can i do to work simulated with the PIDs ? actuall i becomes ONLY the f.error joint 0 following error .
(he goes LINEAR from to to max-ferror ..)

i am stupid ? and the SIM its NOT for simulated a servo ? *g*
thanks for help.

PS: what its the POINT - i found NO samples for optimicing the PID and Co ?
PStart = 0
Pn = 0.5
Pmax = 5
.... then combine with the <I> <D> <F1> <F2> ? automaticly with ala pyhton ?

PPs: i goes to update the "office-pc" with the:
deb buildbot.linuxcnc.org/ lucid v2.5_branch-sim
deb-src buildbot.linuxcnc.org/ lucid v2.5_branch-sim
i hope this its the right way

Fremder wrote:

and the SIM its NOT for simulated a servo ? *g*

No, sim is simulated real time, not simulated servo.
MANY years ago, the old EMC had a simulated motor/machine,
but it was not terribly realistic. Unless you make detailed
measurements to the motors electrical and mechanical
characteristics and all the springiness, friction and masses
of the machine, simulation will be totally pointless, anyway.

Trying to develop tuning parameters on a simulation is
only of benefit for NASA, where you can't operate the
device in its natural environment.

Jon

After reading these posts about servo tuning, I feel pretty good about tuning both servos on my turning center, but before I try that I want to make sure that I am at least close on my values in my "ini" file for my axis, before i throw power to the servos and have a major crash.

Following is a copy of my INI



any help would be greatly apprecieated.

Thanks

Rick

I usually disconnect the connection if possible to do so without loosing the control feedback to the axis ball screw just to make sure my wiring etc is ok and no run away condition exists. If you can jog the servo a bit then connect the servo back up and carry on with your tuning.

We now have a Servo Tuning area... I'd move this post but seems like you can't move a post that is older than the category.

John