2011/9/17 Peter C. Wallace <p...@mesanet.com>: >> >> I have 2 questions: >> 1) I have managed to get 2 joints oscillate around zero, (which tells >> me that they need have PID parameters adjusted). There is a problem >> with a third joint, which just runs away. When I try to change >> something for that third joint, it affects also some of first two. Why >> is that so? For example, if I set Output_scale for third joint from 1 >> to -1, second joint will not oscillate around zero, but run away. > > > There should be no interaction of the axis > > I would do as I has suggested and verify that all DAC channels work as > expected before proceeding. > > interaction suggests a grounding/ analog input problem (do the drives have > differential inputs ( most do) If so the IN+ sould go to 7I48 AOUT and the IN- > to 7I48 ground
Thanks, I will take a look! >> >> 2) How do I solve the situation, when PWM value is +1, but encoder >> position increases in negative direction? That is for the third joint. >> As I mentioned, changing output scale to -1 for third joint will make >> second joint to misbehave. What else can cause that? Should I change A >> and B wires from encoder signal cable? > > I would first set up the encoders so they count in the correct direction for > your axis, and then change the output scale to reverse the PID feedback if > need be. Ok, and how can I do that - fix the the direction of counting? Will changing A and B leads do the trick? Viesturs ------------------------------------------------------------------------------ BlackBerry® DevCon Americas, Oct. 18-20, San Francisco, CA http://p.sf.net/sfu/rim-devcon-copy2 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
