Re: [CAD_CAM_EDM_DRO] servo controllers

Shawncd wrote:

>John,
>Any idea when EMC will be able to to do lathe threading?
>
>
>

No, unfortunately. The HAL (hardware abstraction layer) changes
that will produce EMC2 are going along, I believe. This will allow
a lot of cleaner connections between motion planning and whatever
does the actual motion control. There are some totally unbelievable
kluges in EMC now regarding the special cases, such as homing,
going into and coming out of E-stop, etc. This overhaul is much needed,
and makes all sorts of motion, I/O, etc. into little well-defined modules,
with well-documented interfaces, and a language to connect these
modules to the outputs and inputs of EMC. I believe that lathe
threading will almost drop out of this work, and the only thing that
will take some development will be adding the proper G-code commands
to EMC's interpreter. I have found the interpreter to be almost
incomprehensible, the few times I've peeked into it looking to see
how some G-code command turns into the NML message that actually
does what was commanded. (I admit, I didn't work very hard at trying
to penetrate into the interpreter's workings.)

I hope that I am not being over optimistic about the HAL and threading,
but I did see John Kasunich demonstrate electronic gearing, where he
twirled an encoder, and a stepper motor responded in sync with his hand.
Ths was at the NAMES show this past April.
This is VERY close to what lathe threading is, just electronically gearing
the carriage to the spindle. The only additional tricks to it are to be
able
to sync to the spindle while it is running, and the break back out of the
electronic gearing mode after a certain distance is travelled.

Jon