On Thu, 15 Jul 2010 08:42 -0700, "Peter C. Wallace" <[email protected]> wrote: > On Thu, 15 Jul 2010, Sebastian Kuzminsky wrote: > > > On 07/15/2010 08:54 AM, Peter C. Wallace wrote: > >> Maybe a HAL Comp that uses ddt but tosses crazy velocities > >> (uses previous calculated velocity if index has been detected) > >> would solve the problem > >> > > > > Sounds like a combination of ddt and lowpass. > > > > http://linuxcnc.org/docs/2.4/html/man/man9/ddt.9.html > > http://linuxcnc.org/docs/2.4/html/man/man9/lowpass.9.html > > > > Not quite, I was suggesting tossing bad data so even if the velocity is > filtered the bad data does not contribute to the average >
How about ddt followed by limit? The limit block applies a slew rate limit to it's output. Set the limit about 2x the maximum spindle accel/decel rate, and any wild spikes from reset will be cut down to size, with recovery to the correct value on the very next update - no long tail like you'd get with lowpass. John Kasunich -- John Kasunich [email protected] ------------------------------------------------------------------------------ This SF.net email is sponsored by Sprint What will you do first with EVO, the first 4G phone? Visit sprint.com/first -- http://p.sf.net/sfu/sprint-com-first _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
