Re: [CAD_CAM_EDM_DRO] Re: Digitizers, Renishaw

Smoke wrote:

> True....that's the "hole" idea (pun intended). When the light is blocked
> from reaching the photocell, the circuit is interrupted, thereby indicating
> a point of contact with the part...exactly the desired effect.
>

At the risk of getting admonished or worse I will wander into this subject.
goals: if probe touches object and moves in x, y, or z then sensor should send signal.
so: one uses the ball and groove or multiple ball method of aligning and doesn't trust using the balls as switches then opto
makes sense.
I visualize using mirrors to pass a beam around the circle (triangle).
Use one emitter and one opto sensor. The disk with appropriate masking will then occlude the beam if the disk tips or moves only in
z.
I suspect that one should ac couple the opto output signal and therefore sense only change in signal.

Nomex suit on!

Dave

BTW-reason the disk/probe should not rotate is shifting of the reference point if the probe is not perfectly straight. :-)