Re: [CAD_CAM_EDM_DRO] What is wanted in a controller,

Hi Drew, Dan,

The "stepper motor" jog knob would be incremental also, I believe. One
would need an absolute encoder (with detents) if you wanted to "get
back". *OR*, what about a "feedrate override" display, either LED or on
the screen, that would allow you to get back? cheaper, wouldn't need
expensive ABS encoder. But knob would not be graduated, just
"relative", I think.

If we use a "DRO" approach, then perhaps one could "zero" the knobs,
THEN we'd know exactly where they were! (Zero the knob, and "reset" the
encoder chips to zero).

More thought required. I just ordered a DRO kit from Dan M., that is if
PayPal took my "payment". An hour later, and I have no confirmation.
Get anything Dan?

Alan KM6VV


Drew Rogge wrote:

>
> After reading Fred's explaination of how the "jog" knob on
> his control works I'm pretty interested in that. Having the
> tactil feedback would be nice. It kind of reminds me of how
> the volume and channel knobs work on most car radios now. The
> knob has something in it to provide the "clicks" as you turn
> but the CPU in the radio is really just counting something like
> quadurature inputs to know which way and how much you've turned.
> I've also noticed that if you spin the knob too fast the radios
> will usually miss some of the clicks.
>
> On the feedrate knob I think it's important to be able to
> set/reset the knob to the progammed feedrate. Same for spindle
> speed override.
>
> Drew
>
> Alan Marconett KM6VV wrote:
> >
> > Hi Drew,
> >
> > Thanks for your thoughts! I think I see what you're talking about with
> > the video tape jog knob. I have a high end Sony VCR with a knob that
> > sounds like what you're describing. My remote probably didn't cost
> > $200-300, but I get what you mean. This would be different then a
> > "directly calibrated" jog wheel, which would be more like a manual
> > machine. Two different approaches.
> >
> > The feedrate knob is one I (hobbyist) hadn't considered until these
> > threads. I can see how it would be useful. That sounds more like an
> > absolute shaft encoder. Or perhaps a pot and A/D.
> >
> > Spindle on/off, coolant on/off etc. buttons would be easily added to a
> > pendent. After a few more devices, it makes sense to do it with a PIC,
> > to minimize the "wires" between the pendent and the control panel, and
> > read the various "analog" input devices.
> >
> > Alan KM6VV
> >
>
> --
> Drew Rogge
> drew@...