Design of the Undulating Fin Propulsor with Rajiform Swimming Mode

Abstract

Fishes have evolved remarkable swimming abilities after years of evolution which inspire scientists and engineers to develop new underwater robots that mimic different kinds of fishes. Stingray is a unique species among median and/or paired fin (MPF) mode fishes which undulates the enlarged pectoral fins while swimming. In this paper, a biomimetic prototype design and a developed undulating fin propulsor that mimics stingrays are presented. Kinematic model of the undulating fin is built. The flexibility of the curved surface is checked by the fitting results. Detailed mechanism structure and control system design of the bionic prototype are illustrated. The simulation experiments of the propulsor were conducted on the ground and the results show that an approximated harmonic wave can be generated on each side fin. The feasibility of the motion control method is verified.