Design of flexible tail fin propeller for bionic dolphin

The traditional multi joint bionic fish propulsion system has complex control system, few joints and irregular fluctuation. Aiming at these shortcomings, a multi joint bionic dolphin propulsion system with elastic damping structure is designed. In this paper, according to the motion model and dynamic model of the dolphin, the law of the compound motion of the tail fin is determined. Through the fluid simulation calculation of the tail fin structure, the motion frequency and amplitude parameters are determined, and the motion load of the tail fin is obtained. Based on these parameters, the bionic tail tin propulsion system is designed. In the process of dynamic simulation, by adjusting the material density, rigidity coefficient and damping coefficient of the components, the specific compound motion of the tail fin is obtained. The calculation shows that the load stability of the system is good, but when the tail length is long, the symmetry of the motion is poor, and the damping increases rapidly. Comparing the dynamic results of the system with the pre design parameters, it is found that the bionic propulsion system is stable and feasible.