Les Newell wrote: > That would be FF0. Assuming the friction is directly proportional to > speed then FF0 will increase the output directly proportional to the > commanded speed. It does mean that it will over compensate a bit while > accelerating up to speed but that is fine because you need more power to > accelerate anyway. > Nope, FF1 is proportional to speed, FF0 is proportional to position. Actually, a fix to the bug just found in the PID's I term may be what is needed. A properly working I term will correct any standing error after a short time. Since I think Igor mostly just wants to position to a particular angle and hold it, that should be what he needs. I don't think there is a workable scheme for an "FFF" correction, since it will just keep the motor creeping until other terms overpower it. Possibly the inverse deadband will help, though.
Hopefully, the problem with the I term locking up can be debugged quickly. This kind of error is exactly what the I term is designed to handle. Jon ------------------------------------------------------------------------------ The modern datacenter depends on network connectivity to access resources and provide services. The best practices for maximizing a physical server's connectivity to a physical network are well understood - see how these rules translate into the virtual world? http://p.sf.net/sfu/oracle-sfdevnlfb _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
