Re: stepper-servo system

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "caudlet" <thom@...> wrote:

> Maybe I still don't understand, but it appears to me if you
> used a motor to adjust postition and the gap voltages to measure it,
> it would just simply move down as the material was cut "looking" for
> more material to balance the voltage.

yes that's correct although it may have to move backwards due to arc
conditions etc.

>I don't think complex velocity or encoder posititoning is of use here
>with the tiny amount of moves and velocity you are talking about.

I wasn't suggesting any but I don't see the problem adjusting the
pulse rate to the stepper to give a constant feedrate rather than have
it sit waiting for the top end of a voltage window.

> It sounds like it doesn't matter
> what the actual position really is in the material just that it is
> cutting at the right rate. The feedrate would be determined by the
> voltage change. The more the DC is filtered the slower the > >response.

filter DC?

Graham