On Optimal Energy Consumption Control Method for Tail Fin Bionic Robotic Fish The endurance ability is an important factor to be considered in the practical application of bionic robotic fish. By designing an optimal energy consumption control method, the energy consumption of robotic fish can be effectively reduced. In this paper, the structural characteristics of the tail fin bionic robotic fish are abstracted through the motion analysis of the tail fin fish. On this basis, a simplified dynamic and kinematic model of the robotic fish and a calculation method of energy consumption are established. Then, by changing the oscillation amplitude and frequency of the tail, the change law of the swimming speed is obtained. It is also found that the energy consumption is positively correlated with the swimming speed in general. In order to get the lowest energy consumption swimming mode of robotic fish at different swimming speeds, a series of optimal energy consumption points are obtained at the interval of 0.05ms. The control method of optimal energy consumption of robotic fish is designed by analyzing its distribution law.

Design of a Robotic Fish Based on a Passive Flexible Mechanism In recent years, along with the rapid development of manufacturing, control, sensing and other technologies, biomimetic robotic fish has played an increasingly important role in marine exploration, underwater rescue, water quality monitoring and other fields. This paper designed a robotic fish based on a passive flexible mechanism to realize the fishlike propulsion function. The motion simulation of the designed transmission mechanism was carried out to get the actual curve of the structure. Through the analysis of the force of the fishtail, the preliminary selection scheme of the elastic joints based on the passive flexible mechanism was obtained. Finally, this paper built a robotic fish based on a passive flexible mechanism, which could achieve the motion frequency adjustable from 0.5 to 9 Hz, and the maximum swimming speed reaching 1.05 BLs (BL, body length). This design scheme provided a new reference for the design of the biomimetic robotic fish and had certain practical significance.