  Pneumatic pressure cells with thin metallic spherical diaphragm of shallow
spherical shell configuration linked with vibrating wire pickup or vibrating
cantilever pickup were reported in the past. In order to enhance the
sensitivity of the pressure cell this work considers dual diaphragm structure
fitted with cantilever pickup. The design and development of the pressure cell
with this dual diaphragm structure having cantilever pickup is presented here.
The geometrical design is optimally made as to sense either mono pressure or
differential pressure resources. The cantilevers of the two diaphragms are
excited to produce vibrations and the frequencies of vibrations are determined
by picking up signals from orthogonally arranged opto-coupler links. With the
computed frequency a lookup table is referred to obtain the pressure acting on
the concerned diaphragm. In the external circuits, the average pressure and the
differential pressure acting on two diaphragms are computed. Furthermore
transmitting circuits taking the average pressure and differential pressure in
digital form and analogue form to remote area are presented. Performance
analysis of the proposed mechatronic pressure cell is made and its improved
performance over other pressure cells is presented.
