> ----- Original Message ----- > From: "Marshland Engineering" <marshl...@marshland.co.nz> > To: emc-users@lists.sourceforge.net > Sent: Wednesday, April 6, 2016 7:18:15 PM > Subject: Re: [Emc-users] Servos and Drives PID Values > > Summary of replies > > >It might work better with an inner speed loop and an outer position loop. > Not sure what this means. > > Setting up a dual loop for a torque mode servo setup, would be having 2 PID > loops, one feeding the next, to the drive. You'd set up the first PID (the > position loop) where Linuxcnc sends the position command to its command > input, and the encoder signal to the feed back. The second loop is the > velocity loop, and it receives the velocity signal from the position loop > output as it's command input, and a velocity estimate as the feedback. The > velocity loops output is then the torque command signal that you send to the > drive. > > I have a machine set up this way and it works reasonably well. I have the > velocity loop PID loaded in a floating point base thread running at 5khz (as > well as the read/write to the mesa card). > > I think a better solution for you would be to add tach feedback to the > drives, if possible.
An inner velocity loop and outer position loop as above I think is the method. If velocity signal is noisy I would say tacho is a good method. ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
