Just wondering what's left from LinuxCNC there ) With such intelligent servo drives you just have to stream the position data (you made the new TP for that!). Do you use Ethercat I/O too?
сб, 23 лист. 2019 о 12:17 Herzog Raoul <[email protected]> пише: > dear Nicklas, > > there is no feedback control loop in OpenCN. > Feedback and Feedforward is only inside the drives. > > We use TSD80E drives from the manufacturer Triamec ( > https://www.triamec.com/de/triamec-servo-drives.html). > The sampling frequency for the PWM, current control loop and position > control loop is 100 kHz ! > The setpoint values coming from EtherCat at a rate of 10 kHz are fine > interpolated in the drive and upsampled to 100 kHz. > > One remark regarding our feedrate planning. > At any time, at least one of the constraints is "active", meaning that > either the max jerk is delivered, or the max acceleration, or the max speed. > Sometimes this is called "Bangbang", maybe a misleading term since there > are no jumps in acceleration. > Time optimality automatically leads to this "Bangbang" property. > > best regards, > > Raoul > > -----Message d'origine----- > De : N <[email protected]> > Envoyé : samedi 23 novembre 2019 10:51 > À : EMC developers <[email protected]> > Objet : Re: [Emc-developers] announcement OpenCN, a new fork of LinuxCNC > --> Precalculations > > > dear Nicklas, > > > > of course, feedforwards are utilized (and well parametrized) in the > *drives*, otherwise excessive tracking errors appear. > > > > But this is done in the *drive*, *not* in OpenCN. > > OpenCN calculates physically realizable setpoint values (according to > "optimal control theory"). > > Sounds really good. Physical realisable will be movement calculated with > feedforward of maximum and minimum voltage with a perfect model, sounds > simple but to calculate then it is time to slow down to exactly hit a point > running at the limits is suprisingly hard to get correct for all cases. > > Then there must be some room for the control law. You have gone further > and included unperfect model and dynamics from the feedback in some way or > other? > > > Regards Nicklas Karlsson > > > _______________________________________________ > Emc-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-developers > > > _______________________________________________ > Emc-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-developers > _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
