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"). Since the feedback loop and the feedforward are supposed being well parametrized in the drive, physically realizable setpoint values (=reference signals for positions, speed and acceleration) are well working. best regards, Raoul -----Message d'origine----- De : N <[email protected]> Envoyé : vendredi 22 novembre 2019 23:46 À : EMC developers <[email protected]> Objet : Re: [Emc-developers] announcement OpenCN, a new fork of LinuxCNC --> Precalculations On Fri, 22 Nov 2019 21:59:33 +0000 Herzog Raoul <[email protected]> wrote: > dear Andrew, > > thanks for your positive feedback. > > There were many reasons for us to develop OpenCN : > > 1) of course scientific curiosity ... I'm working for ~8 years in > this field > > 2) but, more important, I had and have customers having problems with surface > quality as feedrate increases. > I'm living in the "watchmaking" western part of Switzerland :-) We > found out that the cause of the bad surface quality problem stems from the > vibrational behaviour of the machine. > And we started to develop special trajectory planning algorithms coded in > Matlab for *precalculating* the setpoint values. > It turned out, that the machining time with our algorithms was ~5 times lower > compared to a high end CNC, while keeping the same surface quality. > But then ... very difficult to get a commercial CNC manufacturer interested > in ... an industrialization seemed difficult. > We decided to make the important step from "offline precalculation" of > setpoint values to online calculation as any CNC does. As control theory is a common problem I work with I am rather interested in these precalculations? Some kind of feed forward? Regard Nicklas _______________________________________________ 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
