Design of a Smart Gas Sensor System for Room Air-Cleaner of Automobile -Thick - Film Metal Oxide Semiconductor Gas Sensor

It is almost impossible to secure the reproductibility and stability of a commercial thick-film metal oxide semiconductor gas sensor since it is very difficult to keep the consistency of the manufacturing environment. Thus it is widely known that the general semiconductor-oxide gas sensors are not appropriate for the precise measurement systems. In this paper, the output characteristic analyzer of the various thick-film metal oxide semiconductor gas sensors that are used to recognize the air quality of passenger´s space of automobile are proposed and examined. The analyzed output characters in normal air chamber are grouped by sensor ranks and used to fill out the characteristic table of the thick-film metal oxide semiconductor gas sensors. The characteristic table is used to determine the rank of the sensor that is equipped in the current air cleaner system of an automobile. The proposed air control system can also adapt the on demand operation that recognizes the history of the passenger´s manual-control.