Dynamics modeling and simulation for a gliding robotic dolphin

Abstract

This paper provides a detailed hydrodynamic analysis of the gliding motion for a gliding robotic dolphin. In order to realize both high maneuverability and long endurance, a novel gliding robotic dolphin is developed through introducing a buoyancy-driven system for the gliding motion. Concerning the particular controllable pectoral fins and horizontal fluke of the robotic dolphin which are significantly different from traditional underwater gliders, a first-principles based dynamic model of the gliding motion in the vertical plane for the robotic dolphin is established. For the sake of determining some key hydrodynamic coefficients including lift, drag and pitching moment, the Computational Fluid Dynamics (CFD) methods are adopted for the dolphin body, pectoral fins and horizontal fluke, respectively. Specially, several prismatic layers are stacked onto the surface mesh for accurate imitation. Finally, simulation results reveal the detailed gliding performance and verify an expected gliding ability of the developed gliding robotic dolphin.