A Sensor Fusion Approach to Odor Source Localization Inspired by the Pheromone Tracking Behavior of Moths

An approach to odor source localization with an aerial vehicle using the fusion of odor sensors, visual sensors, and airspeed sensors is presented. The motion of the tracking vehicle is decomposed into two components - a component normal to the wind direction and a component tangential to the wind direction. The tangential component is controlled with a strategy that moves upwind when odor is detected and moves gradually downwind when odor is lost. The normal component of velocity is controlled by two different algorithms. The first algorithm controls the rate of turning in the plane normal to the wind direction as a function of concentration. The second algorithm controls the rate of turning and the magnitude of the normal component of velocity as a function of the time derivative of concentration. Both algorithms display the potential to declare the location of an odor source in a three-dimensional space.