Conceptual design and recovery stroke mode of a mechanical pectoral fin

This work presents a conceptual mechanical design of pectoral fin apparatus and an innovation of its recovery stroke mode, for underwater biomimetic robot Motion of pectoral fin apparatus was detailed analyzed, simulating natural fish´s 3 kinds motion manners of pectoral fin, and the function of driven pole length was deduced, which could be used for actuators driving. Based on the conceptual design, a new recovery stroke mode was proposed By contrast of the projected area perpendicular to the oncoming flow, between mechanical pectoral fin and fish´s, the fact was found, that recovery stroke mode of the pectoral fin apparatus has less projected area than fish. That may result in less fluid drag during recovery stroke.