Re[2]: digitising arm

Alan wrote:

>About twenty+ years ago, we had "sonic digitizers" (2D) for use in
>Radiation Therapy<snip>3d versions, and used a stylus which created
>a spark that could be heard by the "linear microphones" along each
>axis. Not an arm, but might be an interesting approach.

Alan,

Alltronics (near you, on Zanker) had some "Sonic" 3d digitisers for
sale not too long ago. They consist of a "noisemaker" (ultrasonic??)
wand and a "receiver" which was three microphones on a folding
structure which, when set up, put the microphones at the points of an
equilateral triangle. I don't remember what the S/W format was
(dos/win/etc)? Might be worth a look-see?

Alltronics sells nationwide via mail order catalog, also.

There are several makers of these "sonic" 3d digitisers. Some can be
seen on the web. I always wondered what kind of REAL resolution was
typical, and stayed away. But it seems a neat idea.

Hope this helps.

Ballendo