2011/9/17 Peter C. Wallace <p...@mesanet.com>: > > Since you have no feedback until you get your encoders working, I would just > try getting +- 10V out of the 7I48 by setting the output scale to 10, > disconnecting the PWM .value from the PID loop and setting it > manually in volts with setp ) try +10, -10, +5 ,-5 ,0 etc
Thank You for the suggestion! EMC does receive encoder signal from servo drive (motors have resolvers, servodrive emulates encoder signal and outputs it on a 9-pin serial port connector, from where the signal is wired to 7i48). I am watching "position" pins of encoders from servo drive and they either increase to very high values or decrease to very low values. Actually EMC receives all 6 encoder signals, also 3 from linear scales - I also checked their "position" pins, when pushing machine by hand (motors are detached) and it seems that the increase/decrease in the value of linear scales' position pin matches the actual travel. 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. 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? 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
