Chris Radek wrote: > On Tue, Jan 27, 2009 at 10:08:46PM -0600, Jon Elson wrote: > >> I think this is absolutely the correct way, as the C axis will then >> always follow the path, even when manually moving! >> > > Unfortunately not, since manual motion is currently in joint mode. > No, I was thinking of using axes 0 and 1 at the HAL level to compute the C angle. > > >> And, there's no need for adding C movement to the G-code. When you >> program a single arc move in XY, the C move would have to be programmed >> in linear segments, greatly complicating the G-code. >> > > This was discussed earlier in the thread - rotary axes can move > during arcs and this gives exactly the needed motion. The > calculations for generating this gcode are simple. > > Right, a constant-rate C move at the same time as a G02 arc would stay in sync just fine, I wasn't thinking straight about arcs being exact circular movements only, but of course they are. >> HAL has to be the >> way to do this. You could always use an optional digital output to turn >> this mode off if desired. >> > > I still think gcode is the best way. Jeff's ideas about > auto-generating with a filter are interesting too. > > > That makes more sense. I doubt anybody would be running a vinyl cutter with tool length and radius compensation, so the filter could be pretty simple. Since, as you say, the C axis can be programmed with a single C word that corresponds to each arc move, and add a separate block that sets the C axis before each G01 move, the resulting code would only be a slight increase. I don't know if vinyl cutters usually have any pre-locating of the cutter before each cutting move, or just treat the cutter as a point.
Jon ------------------------------------------------------------------------------ This SF.net email is sponsored by: SourcForge Community SourceForge wants to tell your story. http://p.sf.net/sfu/sf-spreadtheword _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
