capacitance,seat occupancy detection,how
Yet pressuire sensor has to be protective to agressive environment including toxin gas and be robust enough to extreme mechanical force)
We also can make very intelligent sensor capable of giving object recognition indication to object being measured . We goes as in case of flatulent suggestion number 2 , but measure current instead of capacitance by supplying AC through elektrodes.
AC voltage should be granularly increased untill desired value of measurement indication to object is achieved.)
Putting microphone will implemented closed loop feedback system - so sensor will catch also object reaction to measurement attempt.)
Also microphone can be used to start air pump in case of aggresive gas pollutions )
... possibilities are infinite (c)