Bio-Inspired Design for Mechanical and Biomechanical Applications

Abstract

Over the course of billions of years, nature has evolved materials, structures, and morphologies that exhibit a wide range of unique functionalities. Some of these traits are of particular interest to scientists and engineers because inspiration can be drawn from these traits, and applied to a wide range of man-made systems. Thus, bio-inspired design is of great interest to researchers in hopes of improving upon man-made innovations. Bio-inspired design comes in all shapes and forms, but the present thesis focuses on inspiration from two specific aquatic animals: sharks and octopuses. First, inspiration is taken from the morphology of the skin of sharks to design surfaces and structures for engineering applications. Using a combination of 3D printing, experiments, and numerical simulations, this thesis shows that the tiny, tooth-like structures (denticles) that cover the skin of a shark can be used to enhance lift and reduce drag when placed on an airfoil as a bio-inspired, low-profile vortex generator. In addition, this thesis shows that whole surfaces of these denticles with the right set of geometric parameters can be used to reduce drag and improve efficiency in dynamically moving surfaces. Through this bio-inspired design process, insights into the structure and purpose of the denticles on a living shark are attained as well. Second, inspiration is taken from cephalopods, specifically octopuses, to design an extremely versatile soft gripping robot for a wide range of applications. With the novel bending and suction design presented for the soft robot, a wide range of objects can be grasped and manipulated, from flat rigid objects to heavier curved objects. Throughout the course of this thesis, I will demonstrate that using a combination of various manufacturing techniques, experiments, and numerical simulations, the bio-inspired designs presented here not only have important applications in man-made systems such as aerial devices (including airplanes, wind turbines, and drones) and robotics for manufacturing, but also even give insight into understanding their functionality for the animal itself.