On Wednesday 06 April 2016 09:34:36 Dave Cole wrote: > Can you run those drives in velocity mode? > I think that would be a lot easier to tune. > I would avoid torque mode if possible. Life will be easier. > > Dave
Dave, this is something I have not seen well defined in our manuals, nor in the manpages. It seems to me there s/b a PID settings framework that makes it easy to apply this "torque" or "velocity" label to a given setup. The at_pid manpage describes two different strategies by a list of variables it might play with, but does not go so far as to define that one is for torque mode while the other is velocity mode. Some sort of a secret I guess, known only to the initiated and annointed. :( What constitutes the framework in terms of non-zero PID entries for each mode? Or conversely, what entries must remain at 0.0000 for each "mode"? > On 4/6/2016 4:53 AM, Marshland Engineering wrote: > > I finally have my mill table moving under CNC control. > > > > I'm using a 70 volt supply with DCM D6 drives in Torque mode, Mesa > > 7i48 cards, Linear scales for position and 1.2 kw DC brush motors > > (my guess on the power as they are 90 volt motors but no current > > rating) > > > > The only way I can get any control over the travel is setting P = > > 0.5 which of course makes the position accuracy poor. Any more P and > > I get sever oscillation. With the size of motor and the 1m table, > > there is quite a lot of inertia in the system. > > > > Anyone suggest starting values or any other suggestions to get this > > under control. > > > > Thanks Wallace. > > > > > > -------------------------------------------------------------------- > >---------- _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > ---------------------------------------------------------------------- >-------- _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
