Re: [CAD_CAM_EDM_DRO] Synchronizing Two Servo Motors

Steve, I started out w/ steppers but changed "up" do to not having enough
power out of the steppers. It still worked w/ Steppers, it's not to often that
one will die and the other not... maybe lose some steps but a few steps
doesn't bother my gantry. On the other hand my servos need to fault
out [as you pointed out] before Mach stops. However this is a grand
total of 0.025" rack.. again.. not really an issue.

Driving two Step/dir drives off of one set of S/D pins is a no-no in that
it's NOT absolute, there is no way of knowing where each drive is in
relation to the other and whether each drive is seeing an equal number
of steps, your much better off seperating the pulse trains via the control
and slaving them, in the control.

As far as I'm concerned, Mach does it and it IS turnkey [select three radio
buttons in the config settings].. I've been running my machine for more
than 2 yrs this way.. and it works great.

Fwiw

Jarrett

>
> Note that Jarrett's setup (with Mach) can't detect if a motor dies
> until
> a drive faults or a limit is hit. If you use steppers, then the
> drive
> will never fault since there's no feedback. With servos you could
> get a
> drive fault which would stop Mach.
>
> - Steve