Re: [CAD_CAM_EDM_DRO] Re: CNC Etch-A-Sketch, EggBot

Hi Gordon,

I your axis could drive a pot. Connect the pot as a voltage divider,
and digitize the voltage. Might be simpler to just use a third axis.
Then there would be no trig calcs.

Compliant? I just mean a pen mounted in a mount with a little give.
Spring "tracking" pressure. Too stiff a pen, and you'd wipe out the
egg!

Alan KM6VV


Smoke wrote:

>
> What I'm saying here is the probe would look like a flat needle with a round
> pin thru it at some point. this pin would be a rotary axis (like an axle).
> The probe end would then rotate about this point (axle). The opposite end
> of the probe would have some sort of measuring device for measuring the
> angular deviation. We built a similar mechanical gadget at school for
> measuring shotgun bores.
>
> Calculations would only require using be standard trig functions in a single
> plane.
>
> The unit would digitize along a specified length, shift a specified amount
> in the Y direction and repeat as many times as required until the entire
> specified area was digitized. This is pretty much exactly what the
> digitizer on the MAXNC does....except I have no idea how the innards of it
> functions.
>
> IMO attempting to build a radial device that would measure two angles at
> ones would be a lot more than what's required.
>
> I never heard of a "compliant" pen before. What the heck is that?
>
> The only "compliant" pens I have are manual ones that haven't run out of ink
> yet. :)
>
> Smoke
>
> > Hi Gordon,
> A "compliant" pen mount
> > could also "draw" on the egg.
>
> > I didn't ketch how you were going to "sense" on the probe's pivot.
> > Deviation on a probe tip would be simple trig calculation from the angle
> > that is sensed. Radial angle of the 'Z' axis would be a little
> > different approach!
> > > Alan KM6VV
> >
> >
>