> > Friends,
> > First, Sorry for the Off Topic question.
> > Second, I need to design a fixture that will "sense" if a
> > screw is missing on a product. The device in question goes
> > into a test fixture. I would like to have a way of checking
> > for missing screws. Any suggestions?
> > And yes, it will have a PIC in it!
> > Thanks in advance.
>
>
> Weight?

I would try light, an unfilled hole will let light through given that the
geometry of the assembly will allow this.

I/R with modulated at some freq or data train will overcome ambient
interference.



_____________________________

Lance Allen
Technical Officer
Uni of Auckland
Psych Dept
New Zealand

www.psych.auckland.ac.nz

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