Abstract: This paper presents an innovative design for a biomimetic whale shark-like underwater glider aiming at the combination of high
maneuverability and long duration. As a hybrid of the underwater glider and the robotic fish, its pectoral fins and tail can serve as not only
the external control surfaces for attitude regulation during gliding but also the propellers for agile fish-like swimming mode. To verify the
gliding capability of the whale shark-like glider and prepare for future dynamic analysis, the hydrodynamic coefficients, including drag,
lift, sliding force, and corresponding moments are estimated through computational fluid dynamics method. In addition, the hydrodynamic
analyses of the proposed glider and an equivalent conventional glider during steady gliding motion are executed for comparison. Extended
experiments are performed to verify the downward gliding performance. The results reveal that the whale shark-like glider has less drag
as well as higher lift-to-drag ratio and a markable gliding capability in practice. It may offer important inspiration for improving the gliding
efficiency and performance of an underwater glider in biomimetic shape design. 

Key words: biomimetic robot, CFD, hydrodynamic analysis, underwater glider