On Wed, 25 Nov 2020 at 04:01, John Figie <zephyr9...@gmail.com> wrote:
> I looked over the information you provided. It is not clear to me how the > 7i80hv_16_sv.. "SV" sections work. The card provides a PWM output for the > 7i40, the encoder feedback comes back to the 7i40 and then back to LinuxCNC > servo thread where the loop is closed? So is this then just a single > control loop instead of the typical nested Position and Velocity loops that > one would have with a velocity mode drive using velocity feedback to the > drive and position feedback for LinuxCNCs position loop? Yes, this is torque-mode operation. If you only have one feedback device per axis then you can only have one loop.... (Obviously you could use the same feedback device for two loops, but I have a feeling that that doesn't add anything. That is a question for the PID theorists) You could, internally to LinuxCNC, set up a velocity loop using motor encoders and a position loop using glass scales. But I have two machines working well enough for my purposes with a single torque-mode loop. -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1912 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
