Electronic nose-based odour source localization

It is well known that insects and other animals use their olfactory sense in a wide variety of behavioural processes, namely to recognize and locate food sources, detect predators, and find mates. This paper discusses the gathering of olfactive information and its utilization by a mobile robot to find a specific odour source in a room with turbulent phenomena and multiple sources of odour. Three navigation algorithms are compared both with a simple gas sensor and with an electronic nose. Their performance in finding an ethanol source in a room with obstacles is evaluated. The first navigation strategy is based on bacterial chemotaxis. The second strategy is based in the silk-worm moth algorithm to search and track a female moth pheromone plume. The last strategy is based on odour map estimation and maximum concentration following. The electronic nose utilized is composed by an array of different and weakly selective metal oxide gas sensors. The odours are identified and quantified by a pattern recognition algorithm based on artificial neural networks (ANN). The test bed for the navigation algorithms was a Nomad Super Scout II mobile robot.