Bi-modal search using complementary sensing (olfaction/vision) for odour source localisation

Odour localisation in an enclosed area is difficult due to the formation of sectors of circulating airflow. Well-defined plumes do not exist, and reactive plume following may not be possible. Odour localisation has been partially achieved in this environment by using knowledge of airflow, and a search that relies on chemical sensing and reasoning. However the results are not specific, with the odour source only restricted to a broad area. This paper presents a solution to the problem by introducing a second search stage using visual sensing. It therefore comprises a bi-modal, two-stage search, with each stage exploiting complementary sensing modalities. This paper presents details of the method and experimental results

I. Introduction

Over the past 15 years, odour localisation has become recognised as a valuable area of robotics with humanitarian and practical applications, as well as for gaining a deeper understanding of the behaviour of organisms that display odour localising behaviour. Some of the animals that have inspired research are e-coli bacteria that locate nutrients, silk worm moths that find a mate through tracking pheromones carried in the air, and lobsters that seek out food under water. Applications of odour localising robots include detection of drugs, gas leaks, fires in their initial stages, fuel leakage from underground tanks and injured people in search and rescue missions. These applications and scenarios have been tackled by researchers in a variety of ways.