Been there done that. Pain In The Azz.

The trick is to get enough damping into the pendulum so that it doesn't
oscillate. Best results came from eddy current damping using an aluminum
pendulum and strong magnets on either side of the vane. Use optical
position sensing to minimize friction. Strobing the optos gave us
very low power consumption.

We used a welders headband since that gave a nice high mount point.

Today I use the ADXL202 (only need one axis), and with a
FET switch on the filter capacitor, I can strobe it too.

R

"Milton Medicinteknik KB, Vikingstad, Sweden" wrote:
>
> How about a simple head mounted angle/inclinometer ? A very cheap one woul be one pot. fitted on a head band (used for forehead fitted lamps), and a small weight hanging down from the axle that is produting horizontally near an ear. Up/down movement of the head would vary the resistance. Use a high pass filter function.

High pass?? Then all you get is the oscillations...

 If possible, a second could be fitted over the back of the neck, if the
person can tilt his/her head.
>
> Use a small PIC with A/D for relevance ;=)
>
> Sven in Sweden
>
> --
> http://www.piclist.com hint: The PICList is archived three different
> ways.  See http://www.piclist.com/#archives for details.

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.