Robotic Electrolocation: Active Underwater Target Localization with Electric Fields

We explore the capabilities of a robot designed to locate objects underwater through active movement of an electric field emitter and sensor apparatus. The robot is inspired by the biological phenomenon of active electrolocation, a sensing strategy found in two groups of freshwater fishes known to emit weak electric fields for target localization and communication. We characterize the performance of the robot using several types of automatic electrolocation controllers, objects, and water conditions. We demonstrate successful electrolocation both in the conditions in which it is naturally observed, in low conductivity water, as well as in conditions in which it is not observed, in water of ocean salinity. The belief of the position of the target is maintained via a particle filter and refined with each measurement