A fluid-filled seat bladder assembly includes multiple capacitive sensing elements
for detecting variation in bladder deformation due to occupant weight. The bladder
is defined by upper and lower elastomeric sheets that are peripherally sealed by
welding, and the capacitive sensors are defined by metalized films adjoining the
upper and lower elastomeric sheets. The bladder fluid separating the upper and
lower metalized films acts as a dielectric material, and the capacitance or electric
field coupling of each sensor increases when the separation between the respective
upper and lower films decreases due occupant seat weight. The cumulative change
in capacitance or electric field coupling reflects the total seated weight, and
the individual capacitance or electric field coupling changes provide a profile
of the pressure distribution across the seat for improved occupant classification.
The metalized films may be located exterior of the bladder, or may be are formed
on interior surfaces of the upper and lower elastomeric bladder sheets.
