Mechanical design and implementation of a new biomimetic robot fish

A mechanical design method of robot fish is introduced in this paper. Based on this method an autonomous 3-Dimension (3D) locomotion robot fish with two pectoral fins and a caudal fin is developed. The pectoral fin mechanism has 3 degrees of freedom (3-DOFs), which enables the robot fish to realize yawing and pitching motions by controlling two pectoral fins. And the caudal fin mechanism is designed based on fish body wave curve fitting. The forward velocity can be adjusted by changing the caudal mechanism's oscillating frequency. Finally a physical implementation of the robot fish and experimental results are given.