This is mostly for John Kasunich, but anyone else with servo experience is welcome to chime in.
My customer Stuart Stevenson has been having some problems with homing, so I had him send me his entire set of config files. When I got them, I saw that he had what appeared to me to be VERY unusual PID settings. When I run these on my machine, I see that the operation is "stable" but not accurate. By that, I mean that the machine continued moving for MINUTES after I took my finger off the jog key. The following error was in the realm of inches. Stuart says he has no following error to speak of, but I find that hard to believe. Here are his settings : P = 40 I = 4000 D = 0 BIAS = 0 FF0 = 0 FF1 = 1 INPUT_SCALE is 10000 Having so much I term just seems wildly wrong to my experience tuning this PID scheme. I have noteced that the EMC2 D term is much more sensitive than it used to be. The servo interface is my PPMC analog servo board set. He is using Fenner drives from Servo Dynamics. I don't know whether they are set up for velocity mode or torque mode. Since this is so different from my setup, I'm thinking maybe he has his amps set for torque mode. Does anyone have any ideas what is going on, here? Jon ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
