On Mon, 27 May 2019 at 20:15, Maxime Lemonnier <[email protected]> wrote:
> > When I reload linuxcnc, and want to use the MDI, I have to home all axis > But then I'd loose the current position (reset to zero). The machine moves to the home position, but your G554 (etc) offsets stay the same. So you should be able to stop mid job, turn off the machine, restart, re-home and all the work coordinate systems should be in exactly the same place. (This is the case even without the POSITION_FILE.) > Now you're thinking : use > the 'NO_FORCE_HOMING = 1' option. But if I do I loose the ability to use > the > soft limits, which I need. > Have you tested this? My impression is that this all should work, though you might _also_ need to exclude your axes from the homing sequence. > (homing sequence or moving the machine back to 0 and etc is not an option, > because of the precision (0.1deg backlash) of my roatry axes) > I just don't want the machine to accumulate error after multiple reboot. The error shouldn't accumulate. It should, at worst never be more than the backlash. In fact you are more likely to accumulate errors by not homing. As you have servos, can you swap to absolute encoders? That ought to be a complete solution. (And, as an exotic option, my lathe uses a combination of POSITUOIN_FILE and the single-turn absolute nature of resolvers to be absolute without a homing move. Most of the time. I do sometimes have to re-home, I have not quite figured out why yet. I think part of the reason is that I have two complete versions of LinuxCNC on that machine and only one has the updated resolver code) -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1916 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
