On Fri, 2010-05-07 at 12:46 -0500, Steve Stallings wrote: > A general rule of thumb is that the encoder should > offer 10X the resolution of the minimum movement > addressable by G code. > > Following error can be as tight as 3 or 4 units of > encoder resolution on a well tuned system. This > of course does not take into account any mechanical > deviation beyond where the encoder senses the > motion. > > Doubling the encoder resolution would cut FE in half > provided the rest of the system is up to it. > > Steve Stallings > > > -----Original Message----- > > From: Neil Baylis [mailto:[email protected]] > > Sent: Friday, May 07, 2010 11:41 AM > > To: Enhanced Machine Controller (EMC) > > Subject: [Emc-users] Encoder resolution & Following Error > > > > I hope this isn't a really stupid question, but what's the > > relationship between encoder resolution and following error? > > > > For example, the machine I'm building currently has a linear > > encoder of 250 cycles per inch, or 1000 counts. I assume this > > won't allow me to achieve > > 0.001 following error. And I understand FE is also affected > > by machine rigidity, encoder noise, and other factors. > > > > Is there a formula that would tell me what FE would be > > reasonably achievable with my machine? > > > > If I install an encoder with double the resolution, will that > > cut my FE in half? > > > > Neil
IIRC Boeing used 5X as a rule of thumb between resolution and achieved position. Of course, I'm speaking about control surfaces not machine tools. Dave > > -------------------------------------------------------------- > > ---------------- > > > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > ------------------------------------------------------------------------------ > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
