Modeling & developing a single-drive robotic fish

This work simplified tuna´s swimming mode, then designed a single-drive robotic fish propulsion mechanism which including an elastic joint, and established the dynamics model of the mechanism. The thrust, resistance, resistance power on different peduncle oscillation parameters, and torsional stiffness of the caudal fin joint was simulated. The average thrust, maximum resistance and the average power grow with the increasing of the oscillating amplitude and the frequency. When the torsional stiffness of the caudal fin joint becomes larger, the thrust decreases, the resistance and the average power increase. At last, a physical prototype was manufactured and tested. The test result proved that this design can generate thrust in water and it may be used as a robot fish propulsion mechanism.