Effect of Material and Thickness about Tail Fins on Propulsive Performance of a Small Fish Robot

Abstract

The swimming velocity of fish robots are extremely low in comparison with actual live fishes. To investigate the superior propulsive efficiency of actual fish and find measures to improve the propulsive performance of fish robots, a flexible fish robot was developed. The effects of the flexibility of tail fin on the propulsive force were investigated by using the fish robot and three-dimensional CFD. Consequently, the flexibility of tail fin is very important for fish robots to swim efficiently, because the vortex rings generated from a flexible tail fin is useful to maintain reverse Karman vortices for a long time.