AVR-Chat

Okay, well now that we know what you are "REALLY" doing and not
building a tilt meter / inclinometer I can say with confidence the
accelerometer is absolutlely to wrong way to go, and so is a
potentiometer and a gyroscope.

It's optical encoder time.  I had a few here built from Hewlett
Packard.  Unfortunately for you I sold them on eBay a while
ago...probably to a guy trying to build something like what you are
thinking of building.

Google optical encoders, and do a search on eBay.  You will then be
pointed in the proper direction.

The mouse parts could be made to work.  You might need to gear-up the
chopper wheel in the mouse so it gives you enough resolution.  What I
mean is have the optical chopper from the mouse send many pulses be
degree of rotation on your milling machine table.  The could involve
sprockets and toothed belts, known as timing belts.

Good luck with your project.

M5


--- In AVR-Chat@yahoogroups.com, "Richard" <richardt.bradshaw@...> wrote:
>
> Talk about having the answer in the palm of your hand. I think the 
> mouse could give enough accuracy. I wanted to play around with an 
> accelerometer so I guess I was trying to make the problem fit the 
> solution. The project is to make a digital display for a rotary table 
> for my milling machine. For those not familier a rotary table sits on 
> the milling machine or lathe and allows you to cut at points around a 
> centre, cutting gears for example.
> 
> There have been lots of interesting answers on this thread many 
> thanks and if there any other novel ideas I would love to hear them. 
> Rich
> 
> --- In AVR-Chat@yahoogroups.com, "Rick" <eprom999@> wrote:
> >
> > --- In AVR-Chat@yahoogroups.com, "David VanHorn" <microbrix@> wrote:
> > >
> > >  the capactive sensors that they use in digital calipers look 
> pretty
> > good.
> > >
> > 
> > Yes good suggestion.
> > 
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > Consider this-
> > Take apart a computer serial ball mouse. In there you will see two
> > optical breaker wheels, one for the X axia and the other Y.  If your
> > mouse has a scroll wheel, you'll have a similar thing there.  It
> > wouldn't take much imagination to adapt those parts to a Do It
> > Yourself inclinometer.  The way these work is the mechanical wheel 
> is
> > spun and "chops" a beam of invisible infra-red light striking a
> > photo-transistor.  It does so in a fashion which allow detection
> > circuitry to determine which direction the wheel is spinning too. 
> > Cannibalize a mouse for these components and build your inclinometer
> > from that.
> > 
> > If you are designing a product to market as an inclinometer look at
> > these sensors:
> > 
> > http://www.spectronsensors.com/tilt.html
> > 
> > They are capacitive.
> > 
> > M5
> >
>