EtherCAT Servo Tuning and LinuxCNC PID Tuning

Hello, i am looking for some guidance on the interaction of LinuxCNC PID Tuning +  EtherCAT + Servo Drive Tuning.

Would i still need to setup  PID + FF components in the .hal file and .ini file to tune a ethercat system or should all the tuning be in the drive only ?  or a combination of both ?  i would think the servo and the drive are tuned for being dynamic and critically damped to step responces then LinuxCNC  tuning terms are used to reduce following errors.

I have grown my .hal and and .ini file from bare bones and i am unsure on what i need to add to make a PID system work with ethercat.

I am not having any sucess in reducing following error, and my feeling is i need to alter gains in Linuxcnc.
as most people are using steppers and i am using AC servos over ethercat i have not been able to find much direction of how to setup files to enable the calibration feature to work with ethercat. i get an error opening the calibration module saying no tunable gains are in the .ini file

i realize its not as simple as adding the gains to the .ini file
looking at some examples do i need to load the following into a .hal file:-
load at_pid num_chan=2             (for two axis system)
addf pid.0do-pid-cals servo-thread  (for each axis)
set pid.0.Pgain [JOINT_0]P            (for each gain)

then add the gains to the .ini file ?

does anyone have any insight into this type of configuration.








 

Hi Tommylight

I am only using EtherCAT drives.
No Mesa or parallel port.

yes the encoders are reporting back, but to the drive, and the drive is sending the following info back to LinuxCNC
"actual-position" and "actual-velocity"

LinuxCNC is then sending out to the drive
"target-position" and "target-velocity".