Effect of Straight-wing Pectoral Fin Motion on Propulsive Performance of Robotic Dolphin

The cycloidal propeller can provide thrust in the range of 360° of the plane, and applying the cycloidal propeller to the underwater robot can allow the robot to complete more complex movements. This paper proposes a straight-wing pectoral fin dolphin model, which can realize a variety of underwater movements. First, cycloidal propellers are installed on the left and right sides of the pectoral fin of robotic dolphin, then a straight-wing pectoral fin dolphin model is established. The thrust generated by the straight-wing pectoral fin is evaluated through the blade element theory and finally fluid calculation software is used to simulate the movement of the robotic dolphin, including straight forward, diving and turning movement. Analyzing the thrust and combined force generated by the left and right cycloidal propellers in each movement mode can obtain the conclusion that the cycloidal propeller can well meet the various movement states of the robotic dolphin. It is a good choice to apply cycloidal propellers to the underwater robot.