A practical method for simulating pectoral fin locomotion of a biomimetic autonomous underwater vehicle

Abstract

In this paper, a practical method to simulate pectoral fin locomotion of a fishlike AUV testbed is presented. Basing on a blade element synthesis scheme, the authors developed a simple mathematical model to evaluate the hydrodynamic forces acting on a pectoral fin in feathering motion and lead-lag motion. The pectoral fin is treated as a number of moving blade element, the lift, cross flow drag and added inertia acting on each blade element are evaluated as a two dimensional oscillating thin foil and they are described in the fin-fixed coordinate system. These forces of blade element are transferred to the fuselage-fixed coordinate system and then integrated to obtain the total forces acting on a pectoral fin. Kato's data from model test and calculation on a pectoral fin of a bass are cited to compare with the corresponding calculation results by the present simple mathematical model. The quite satisfactory agreement confirmed the validity of the simple model for evaluating the hydrodynamic forces of a pectoral fin. On this base, the previously developed computer program for simulating body-tail undulatory locomotion is then extended to simulate the pectoral fin locomotion of a biomimetic autonomous underwater vehicle