>    What were those other sensors you were talking about?  
> 
>    Regards,
> 
>    Chris Chapman
>   
>

None that you do not already know but I was thinking if you could
use buoyancy to offset gravity it may be possible to get longer
periods using very small springs with large masses and the fluid
providing the bouyancy would possible provide the damping.
I think such a thing might be too sensitive to temp or pressure changes tho.
But you need a specific gravity for the mass in the range of 1.1 to 1.05
that of the fluid to be used. Possibly with the science of fluidics
you might make a pressure amplifier that will  amplify static pressures
caused by a moving container holding a liquid that acts as the stationary mass.
Fluidics is a science like electronics that was invented to
make circuits that are immune to RFI but they are limited to under 40KHz.
The Mass would be slightly denser then the fluid used.
Mercury as a liquid is out of the question due to poisonous effects.
Possibly Salt water or some other relatively safe solution to increase density.

Regards;
geoff
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