Could you solve the noise issue with a phase-locked loop? THis takes advantage of the fact that the spindle has momentum and the accelerating forces are limited.
It is a common technique in electronics, you build a good, clean local oscillator and then take your frequency measurement from that, rather than from the noisy real-world data. But at the same time, you compare the phase of the local oscillator with the real data and make tiny adjustment to the local oscillator. What is really happening is that you only look at edges if they happen near the expected time and weigh them, scoring to how near the expected time so statistically almost all the noise is ignored. You can try averaging, but it does not work nearly as well and has a long lag. On Wed, Jul 21, 2021 at 1:19 AM andy pugh <bodge...@gmail.com> wrote: > On Wed, 21 Jul 2021 at 05:36, andrew beck <andrewbeck0...@gmail.com> > wrote: > > > > Andy what do you think is the max rpm that this will read reliably do you > > think? > > It will handle a higher speed than a full quadrature setup as it only > needs to see one edge. > I have run it up to 16000 rpm (in the video) with a 50,000ns base thread. > > The problem with counter-mode is noise rejection, noise is seen as > pulses and gets added to the position. (This isn't unique to the > missing-tooth index, this is counter-mode in general) > > -- > 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 > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
