Re: Scanner/Digitizer skip function/probe details?

Alan M wrote:

>Curious, I wonder what Otto did, build a library? a TSR?
>I'll try to contact the Motion Group.

Alan,

To be quite honest, I got tired of trying to get an answer to my
questions from Otto, so I don't know what he used for 'hooks'. Dave
Downs used to be the hardware guy at TMG. Good luck.

>Can give me a snippet of gcode to demo these two commands? So any
>gcode program SHOULD be able to digitizing? I saw a line marked
>M61 on the MaxNC interface, might have been a typo.
> G61 X 1.0 Y 0.0
> G31 ?

Yes,but. That would be correct for any gcode control program written
to support the 'skip' function. The 'skip' function of Gcode is a
linear interpolated move. So just think of writing a G01 type
command. The DIFFERENCE IS, if the input bit being 'watched' (by the
control) changes state, the motion stops immediately! So
the 'destination' of the skip command coords need to be far enough
into the part being digitised to assure contact. The skip function
will cause a control alarm if the coords are reached WITHOUT 'inout
at the skip bit'.

G31 x5y3z-1

Most commercial controls have user- accessible variables which
include the current coordinates. 'Reading' these coords to a file
completes the act of digitising.

From memory, I don't know if the MaxNC code is G61, M61, or something
else...

>We never did come up with a digitizer design! You mean we have to
>BUY one?
>Alan

I would love to see the list share thoughts on a digitising probe.
Both by explaining what's out there and how it works (MaxNC, Larken,
Renishaw, Roland picxa, etc.) and then by working to create a probe
we all could build!?!

Hope this helps.

Ballendo