Sensor arrays with only one or several transducer principles? The advantage of hybrid modular systems

Artificial olfaction by means of “electronic noses” aims at the determination of chemical features to characterize molecules, odors, environmental conditions, process parameters, etc. In order to achieve sufficient discrimination a broad spectrum of independent features has to be determined. Since the choice of suitable materials for each individual transducer is limited, different transducers have to be combined in a sensor system to obtain a sufficiently broad discrimination power. This is illustrated for typical examples chosen from the food and textile industries which illustrate the advantage of such “hybrid modular systems”.