Jon Elson wrote: > John Kasunich wrote: >> Jon Elson wrote: >> > I have no idea how hard it is to do better with this lookahead, >> >> It's hard. :-( >> >> That's the rub - if there is a discontinuity the machine has to slow >> down. But it doesn't know there is a discontinuity until it gets there. >> (Or in EMC's case, until it gets within one segment of there.) > Well, then, what is the difference between G64 and G64 P0.0005 ? > In this particular program, it makes a 4 minute difference, or > a factor of 15:1 ! it still didn't get up to the programmed > feed rate, but it got a lot closer. I think I must have left > the file with the 60 IPM feedrate in it, and it did 6.28 inches > in 17 seconds, or 22 IPM. > > I can understand horrible performance in G61 mode, that would be > expected. >
Maybe the lines in this program are close enough to collinear that when you give G64 a tolerance to work with Jeff's code is combining bunches of them into much longer segments that allow much higher velocity. I think G64 without a tolerance can only blend moves that are exactly tangent - that would mostly apply to paths made up of lines joined by arcs. Regards, John Kasunich ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
