Design and manufacturing a bio-inspired variable stiffness mechanism in a robotic dolphin

Abstract

To maximize the dynamic performance; especially swimming; of a robotic fish or an underwater vehicle, lots of research of mechanisms and actuators have been conducted. Among them, the compliance of the structure can help the robotic fish or the underwater robots to increase the thrust. Also, when oscillating frequency of a propulsion system increases, the stiffness of the caudal fin should increase to increase the thrust of the robotic fish. Therefore, the variable stiffness mechanism is needed to maximize the thrust of the robotic fish. In this paper, we present a design and manufacturing procedure using our bio-inspired variable stiffness mechanism which was developed before. We find the appropriate design of the bio-inspired variable stiffness mechanism for applying to a robotic dolphin. The novel variable stiffness mechanism was designed using the inspiration of anatomy of a fluke. Tendons which are used for changing the stiffness are arranged from dolphin's anatomy. This design and manufacturing procedure can be helpful to some researchers who try to apply the variable stiffness mechanism using flexible material. © 2013 Springer-Verlag Berlin Heidelberg.