Bio-Inspired Fins for High Performance Bodysurfing/Boarding

Abstract

In the last 35 years, bodyboarding and body surfing have increasingly become world-renowned sports. In line with these developments, the industry has been striving to constantly develop better equipment to allow athletes to create and maintain a competitive advantage. Accordingly, the aim of this thesis was to design bio-inspired equipment that provide a drag reduction and increased stability to assist and improve athlete performance, as well as investigate how flippers can increase swimming performance. To do this, Auckland University of Technology (AUT University), worked alongside one of the leading bodysurfing equipment designers and manufacturers, FCS and Surf Hardware International, in an industry-sponsored research project. A new bio-inspired hand planes was designed based on sea turtles' carapaces characteristics. This thesis elaborates on the design and development of the hand plane through computational fluid dynamics (CFD) simulations. Validation experiments for drag and stability testing were conducted using a pulley with force sensors, and the product was compared to existing top equipment in the marketplace. In parallel to the hand planes, a flipper dynamometer (dyno) was developed to understand how fins increase the athlete’s performance and the aspects that lead to a good fin design. The flipper dyno went through an engineering design process, where the design was based on derived kinematics developed from the locomotion of flutter kicking. Flipper testing was conducted using existing flippers from Surf Hardware International, where each flipper's thrust, lift, and power consumption was assessed. The result of the bio-inspired hand plane indicted a drag reduction, increased stability, and superior performance over existing products, leading to noticeable gains for an athlete. The ideal designed flipper would optimize vortex generation to create a high thrust per power ratio.