The “Envirobot” comprises several special-purpose modules, which constitute it’s eel-like design, according to a press release on the l’cole polytechnique fdrale de Lausanne website.
The purpose of the modules are twofold. First, each has a small electric motor that lets the robot swim like a water snake. Secondly, each segment has a unique sensor for gathering different data and measurements.
More modules can be added as needed. The robot can swim on a route, or make its own way through a body of water to find the source of pollution, a researcher explains in the EPFL news release.