Swimmer (BEAM)
In BEAM robotics, a swimmer is a robot that functions on or in a liquid environment. These are sometimes referred to as aquabots or aquavores (the latter being a misnomer, as they are not "water eaters"). Swimmers include various designs, but usually lie within a device class that can be delineated as a watercraft, usually a boat but includes any vehicle designed to move across (or through) water.

Genera
 Boatbots : Self-propelled on the surface of a liquid; construction akin to surface watercraft.
 Subbots : Self-propelled under the surface of a liquid; construction akin to submarines.

References
 Seale, Eric, "Aquavore". The EncycloBEAMia, 2003.

External articles
 Northeastern University, Biomimetic Underwater Robot Program (BURP) 
 "Robot fish to resurrect fossils" Sci/Tech, BBC, February 25, 1999.
 "Robofish splash down in Tokyo". BBC, 16 March, 2000.

BEAM robotics