Directional electronic nose setup - results on the detection of static odour sources

The chemical monitoring of wide public areas such as subways, airports, commercial, and industrial facilities, searching for illegal or dangerous substances is nowadays one of the most important issues of risk avoidance activities. The system here described adds a valuable contribution to these activities as it proves the feasibility of the simultaneous mixture identification and mapping using a setup composed of a directional anemometer, and an electronic nose. Both systems are based on low cost technologies. The anemometer consists of four self-heated thermistors assembled around a deflecting structure, and a fifth one for compensating air temperature changes. The electronic nose is based on an array of four metal oxide gas sensors. The attained results show a clear success in the detection of two odour sources, and on the estimation of their directions.