This article presents a novel localization scheme for free-swimming small underwater robots in a large-scale environment. Accurate localization technology has always been a challenge for small underwater robots since the underwater lighting conditions can limit their vision, while the multipath interference issue occurring near a wall plagues the sonars. By contrast, some kinds of fish perceive their positions by sensing the electric field in their environment, giving them the ability to accurately localize in underwater environments. Inspired by the electric sense behavior in fish, this article proposes a large-scale localization scheme based on electric sense for small underwater robots. Our scheme includes an electric sense-based hardware solution and localization methods.
