Re: [CAD_CAM_EDM_DRO] Re: EMC Continuous Contouring

andy@... wrote:

> John - Thanks, I agree a single 360° arc should be smooth, but I am
> concerned that an arbitrary program not pause at any point. Andy
>
> More info : A rectangle with filleted corners appears to go around
> with no pauses, perhaps there is something wierd about starting an
> arc after another arc, or 4 decimal places not enough for a smooth
> transition. Andy

No, I have a program which generates a smoothly-moving sort-of-a-spiral,
out of a long list of 90 degree arcs, and it moves smoothly throughout the
whole thing. The reason I call it sort-of-a-spiral is that each arc sector
has a constant radius throughout it (as that is what a G02 or G03 does)
but each arc has a larger or smaller radius than the last one (depending
on which way it is going). The ends of the arcs are arranged to adjoin
exactly. This thing will make 20 or 30 turns around the circle, without any

hint of a jerk or pause where it moves to the next arc sector.

Now, I do remember there was a quirk in a particular version of EMC sometime

in the year 2000, where it accelerated at the end of every move. If this
acceleration happened quickly enough, it might look like the machine paused
for an instant at each 'corner'. So, what version of EMC are you using?
Is it stepper or servo, and which RT module are you using? Steppermod.o,
Freqmod.o or stgmod.o?

Jon