Analysis of fish and bioinspired robotic fish swimming together in a water tunnel

In this study, we investigate the interactions between individual Golden shiners (Notemigonus crysoleucas) and robotic fish swimming together in a water tunnel at constant flow velocity. The robotic fish is designed to mimic its live counterpart in the aspect ratio, body shape, dimension, and locomotory pattern. Fish behavioral response is experimentally analyzed as the robot's tail-beat frequency is varied and particle image velocimetry is utilized to investigate the flow structure behind the robotic fish. Experimental results show that the attraction of Golden shiners for the robotic fish is maximized when the robot beats its tail as the live subjects. In this condition, fish swim at the same depth of the robotic fish, which corresponds to the region of the water tunnel where hydrodynamic return is most likely to be relevant.