John Kasunich wrote: > Write down the PID gains that work when the scale is 18400. Then, since > you are dividing the scale by 360 to get 51.1, you should be able to > also > divide the gains by 360, and the resulting PID results should be > identical. > Take the old gains, divide by 360, and try them as a starting point for > tuning. > This makes perfect sense to me, but I sure couldn't get it to work like that when I had the same situation. (This was several years ago, before some significant changes in EMC, so that experience may no longer apply.)
I think the basic problem is that the encoder count is by necessity granular, and a lower INPUT_SCALE "magnifies" that granularity. So, a move of so many user units is fewer encoder counts, therefore the apparently flat periods between counts last longer, the counts are farther apart in TIME. The only possible fix to this is velocity estimation, if you are forced to use the raw encoder counts you can't get around the granularity. Jon ------------------------------------------------------------------------------ Come build with us! The BlackBerry® Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9-12, 2009. Register now! http://p.sf.net/sfu/devconf _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
