INTELLIGENT GAS-MIXTURE FLOW SENSOR

A simple way to realize a gas-mixture flow sensor is presented. The se nsor is capable of measuring two parameters from a gas flow. Both the flow rate and the helium content of a helium-nitrogen gas mixture are measured. The sensor exploits two measurement principles in combinatio n with (local) information handling in an artificial neural network. A n analysis of the measurement principles is given and the IC-compatibl e realization process is described. The sensor is simple to integrate with other micro gas-handling components such as valves, pressure sens ors, etc. The sensing elements are combined with a small electronic ci rcuit in which the artificial neural network is implemented. The exper imental results are very promising.