2009/10/2 Alex Joni <alex.j...@robcon.ro>: > >> G90 G1A-10 would rotate ccw all the way back from where it is to -10 > > All the way meaning more than one rotation?
I think it rather has to. I am thinking in terms of acting the same way as a linear axis. Imagine milling a 2-start, 2-turn worm, you would expect: G0 X0 Z2 A0 G1 Z-5 G1 A720 X100 (Cut one way) G1 Z-10 G1 A0 X0 (Cut back twice as deep) G0 Z2 G0 A180 (position for second start) G1 Z-5 G1 A900 X100 (first cut, second lead) G1 Z-10 G1 A180 X0 (second cut, second lead) To work. However, you could decide that rotary moves of greater than a full turn always have to be G91 moves, and I suppose that would be valid, if not agreeable to all. You might want a hybrid approach where G0 always takes the short way round, but G1 unwinds. That might cause problems with non-round work. Perhaps you could invent G1.1 and G0.1 which are "take the shortest route, but keep the machine coordinates that the full unwind would have had." The only optimal solution is for the interpreter to be psychic and to know what the user wanted. Discussion on IRC last night mentioned that the position is stored in a double-precision float which as approx 16 digits of resolution. That means that you can set the rotary axis limits to 10E10 and still have better than 1/1000th of a degree precision even at the end points. At 10 revs per second it would take you a couple of years full-time spinning to hit the limit, so there is no practical difficulty with using G10 L2 as a reset-to-zero. -- atp ------------------------------------------------------------------------------ Come build with us! The BlackBerry® Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9-12, 2009. Register now! http://p.sf.net/sfu/devconf _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
