A robotic fish developed by Drexel engineers could be the key to developing more sophisticated, unmanned and automated marine systems for the United States Office of Naval Research.

The College of Engineering’s Laboratory for Biological Systems Analysis, led by James Tangorra, an assistant professor of mechanical engineering and mechanics, received a $1.1 million pledge over the next three years from the Office of Naval Research to research the multifunctional nature of rayed fish fins using behavioral observations, robotic and mathematical models.

“This grant provides us the opportunity to conduct detailed behavioral and neuromechanical studies of the fish and to use the results to inform the design of very advanced models of the fish’s propulsive and sensory systems,” says Tangora, whose team will collaborate with Harvard University and the University of Chicago.

The robotic fish, which is modeled after a bluegill sunfish, is being used to understand the movement and sensory abilities of fish fins.

“Although we’ve mainly considered the pectoral fin as a propulsive device, it’s highly likely that the fin is also a very sensitive sensory system,” Tangorra says of the real, cold-blooded fish. “The pectoral fin has afferent nerves and free nerve endings throughout its webbing.

“We are investigating if these sensory nerves provide information that is used to make propulsion more effective and that helps the fish sense and interact with the water and other fish,” he adds.

The bluegill sunfish was chosen as a biological model because it represents a class of fish that use multiple fins in many different fin gaits acting on an unstable body to move through their aquatic environment.

Tangorra and his team hope to gather knowledge from the study for the Office of Naval Research to use in developing an unmanned, autonomous platform that could help advance naval capabilities in MCM, ASW, swimmer defense, surveillance and inspection and identification of hulls, harbors and piers.