On Wed, Aug 18, 2010 at 08:38:40AM -0700, Kirk Wallace wrote: > > I still contend that encoder feedback on a stepper system has no proven > advantage
I saw a machine at CNC Workshop that was set up with encoders and steppers. It still did step generation in position mode, exactly as it would without encoders. The encoders were used as position feedback so EMC could monitor the following error and stop the machine if it was not at the expected position. I see a very real benefit here: if the machine crashes, or even if you just program way too heavy a cut and an axis motor stalls, the machine will stop and the spindle will turn off, and it will give you a following error on the screen. That's night-and-day better than blindly continuing to cut stuff in the wrong place. The second setup that people seem to be trying is to use velocity mode stepgen and encoders or scales. I think there are problems with this setup (mostly the fundamental "pid and steppers don't match" problem) and I think the jury's still out as to whether it's a promising setup. Chris ------------------------------------------------------------------------------ This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
