An experimental study of the morphological influence of fishtails through reciprocating motion

Fishtails can generate hydrodynamic propulsion, control, and more underwater through various structures and geometries. In particular, preliminary studies have shown that the shape of the tail can increase propulsion by up to 20%. This study performed various morphological analyses from a hydrodynamic perspective by mimicking a fishtail. Even with the same area, the width and size of the vortices generated underwater varied at flow velocities below 1.0 m/s. The asymmetry required for directional control was also confirmed through parametric experiments. In the future, this research will be utilized to implement underwater robot control.