The invention discloses a novel modular bionic
underwater robot based on full-flexible pectoral fins. A hydrodynamic module of
eagle ray pectoral fins is analyzed, and motion of the pectoral fins is decomposed into vertical bending
flapping in the vertical body longitudinal axis direction and twisting motion taking the vertical body longitudinal axis direction as the axis. The whole
robot comprises a sectioned main body, a left flexible pectoral fin module, a right flexible pectoral fin module and a
tail fin module, and a group module is formed by connecting fin connecting parts; the left and right flexible pectoral fin modules are identical in structure and are in mirror symmetry; a pectoral fin framework adopts a structure similar to that of a plane rib, a symmetrical airfoil is taken as the basic shape, and the pectoral fin modules with streamline sections are spliced through serial connection of straight pectoral fin
trunk bones and steel wires. A large steering engine and a small steering engine are arranged at the root and the tip of each pectoral fin to control vertical
flapping and twisting motion of each pectoral fin. Through adjustment of motion amplitude, motion frequency and
phase difference of the two steering engines of each pectoral fin, different pectoral fin motion postures can be realized, and fish body motion can be finished better.