Real-Time Feedback-Controlled Robotic Fish for Behavioral Experiments With Fish Schools

Integrating robotic agents into animal groups creates significant opportunities for advancing experimental investigations of collective animal behavior. In the case of fish schooling, new insights into processes such as collective decision making and leadership have been made in recent experiments in which live fish were interacting with robotic fish driven along preplanned paths. We introduce a new cyber-physical implementation that enables robotic fish to use real-time feedback to control their motion in response to live fish and other environmental features. Each robotic fish is magnetically connected to, and thus moved by, a wheeled robot underneath the tank. Real-time image processing of a video stream from an overhead camera provides measurements of both the robotic fish and the live fish moving together in the tank. Feedback responses computed from these measurements are communicated to the robotic fish using Bluetooth. We show results of demonstrations and discuss possibilities that our implementation affords for new kinds of behavioral experiments with fish schools.