Thrust analysis of the undulating ribbon-fin for biomimetic underwater robots

Biomimetic underwater robots have been paid more and more attention because of high efficiency, high maneuverability and low-noise. The undulating ribbon-fins used by rajiformes and gymnotiformes show better maneuverability than those of other fishes in turbulent water. So the undulating ribbon-fin propulsion is analyzed for biomimetic underwater robot design and optimization in the paper. The geometric model of the ribbon-fin is set up in Cartesian space. The undulating motion of the ribbon-fin is expressed in trigonometric functions. And the ribbon-fin has been divided into many small elements to compute the force acted on the small element. All the forces acted on the elements in one undulating period are summed, and the average thrust for one undulating period of the ribbon-fin is obtained. The simulation results show the influence of several important parameters on the ribbon-fin thrust. And an experimental platform is built and several experiments are carried out. And the difference between the results of simulation and experiment are discussed further.