Odor-Based Navigational Strategies for Mobile Agents

Although most species are sensitive to various chemicals, and olfactory skills such as search strategies for finding nutritious substance are seemingly simple, these basic skills are still not fully understood. Traditionally, chemotaxis has been considered as the fundamental chemosensory navigational mechanism for most species. Previous studies have demonstrated, however, that biased random walk is the more fundamental navigational strategy in various types of diffusion fields. Biased random walk is a robust and slow search process, but it has been shown that its efficiency can be enhanced if it is combined with chemotaxis. The present article summarizes previous findings of the authors in olfactory navigation and extends the work to searching in dynamic flow fields, including turbulence. In addition, a cooperative, multi-agent search method has been investigated and shown to be successful in enhancing search efficiency. The significance of these findings is discussed in the context of future plans to implement these strategies in experimental mobile robots.