Re: digitizer arm

Dave, Ballendo,

A ground 5160 (stainless?) rod at Rc (Rockwell?) 50; so the strain gage
would be ON the rod? I was guessing it could be between rod and a tip?
I had a VP ENG. wanting to use strain gages to add a "dial" to a
microwave sweep generator. I ended up adding a shaft encoder to the
front panel, he wasn't satisfied with the strain gages (yet).

You mentioned a dial indicator. If one could connect a dial indicator
hand to a shaft encoder... or how about the little glass opto-sensors
used to sense head position in some (old?) hard disks I've seen?

Alan

dave engvall wrote:

>
>So this would be analogous to putting a long travel dial indicator in >the Z axis and
>dragging it along with the x and y?
>
>Dave
>
>
>dave engvall wrote:
>
> Alan Marconett KM6VV wrote:
>
> > Dave, Ballendo,
> >
> > A thread a few weeks back was talking about an electronic "center
> > finder". Which might benefit a little from this digitizing effort.
> > Could a strain gauge (or 2, or 3) be used as the sensor in a center
> > finder or digitizing arm?
> >
> > Alan
> >
>
> Certainly just the reverse of the ruggedized joystick used on some of the military fighters. 2 D should be fine. 3 D might be a
> real problem.
> use a piece of 5160 ground rod at about Rc 50. I should think one would want to be very careful about coming close to stressing it
> close to yield. .... but then if you do the strain gages will tell you. ;-)
>
> In 3D one would just load the end until it flexed..and in any case to get repeatable results the servo would load the probe to a
> given stress everytime.
>
> Dave