digitizer debouncing

ballendo@... wrote:

> DougF wrote:
> >Continuing on my review of cheap off-the-shelfers which can possibly
> >be modified for digitizing is the: - $17.95 Enco edgefinder
> >I don't know you'd get cheaper than that!

> I'm glad you keep finding these alternatives! They may work well for
> some people.
>
> What you are giving up is the ability to probe deep recesses (these
> edge finders have short "probe" length. Also the ability to change
> tips to deal with the geometry you are digitising, and to model the
> cutter...

I completely agree. Perhaps I should have made it more obvious
the intent was to modify the cheap 3D ($130 Signal Lite) and
2D ($49 and $18 Enco edgefinder) probes by:

top end:
- installing some sort of auto re-centering break-away mechanism at
the top (ie a gimbal, or universal joint, or springs, or.... ) to handle
repeated collisions (caused purposefully in order to maximize digitizing
speed).

bottom end:
- installing off-the-shelf ruby tipped probes onto a "sleeve" which
fits over the various 2D & 3D probes. The top of the sleeve is a
cylindrical hollow to fit the probe, and the bottom has threads to
accept standard ruby-tipped stems.
- to utilize the 2D edgefinders in a 3D digitizer mode, this sleeve would
have the feature that would detect vertical contact also
(ie ribs on the interior sleeve which engage the contacts upon vertical
movement).

Further, I suggest a large diameter probe tip (pingpong ball sized) be
initially used to generate a "roughing" digitizing path (in order to
subsequently calculate a more optimal "finishing" digitizing path),
in order to minimize overall digitizing time.

I'm sure the "bottom end" will work, I'm just trying to think of a
good collision breakaway-and-recenter mechanism for the top end.

... maybe I should post a sketch if my explanation is still unclear...

Doug Fortune