Biomimetic Shark Skin Design: The Bristling Effect of Denticles

Abstract

This thesis explores the fabrication of biomimetic shark skin, focusing on actively controlling the bristling effect of denticles, inspired by the passive bristling effect observed in the skin of Shortfin Mako sharks. By examining the natural structure and functionality of shark skin, the research aims to replicate its unique properties using innovative fabrication techniques. A review of previous methods for replicating shark skin structures led to the selection of an indirect fabrication approach, driven by the necessity to integrate an actuation mechanism. Drawing inspiration from soft robotics, the study identified Nitinol, a shape memory alloy, as the optimal material for actuation due to its significant force exertion and seamless integration into the silicone shark skin.
Experiments were conducted in a water tank, testing various configurations of biomimetic shark skin to evaluate the performance of the integrated actuation mechanism. The initial findings demonstrated that Nitinol wire actuation within a silicone matrix effectively mimics the bristling mechanism, even in aquatic environments, showing sufficient strength to counteract water flow. While this research successfully demonstrated the feasibility of integrating actuation mechanisms into biomimetic shark skin, further studies are necessary to optimize the design for practical applications.