From Natural Complexity to Biomimetic Simplification: The Realization of Bionic Fish Inspired by the Cownose Ray

Features of fish-like environmental compatibility and maneuverability have attracted bioinspired design researchers worldwide to contemplate the practical applications of robotic fish. This article presents a conceptual design for and the development of a robotic fish inspired by the cownose ray. We extracted essential biomimetic parameters of the cownose ray to develop reasonable simplifications of the body shape, the mechanical structure design principle of the multijointdriving fin rays, and the motion principle. The practical motion abilities of the bionic prototype's internally driven skeleton are calculated theoretically and compared with its natural model. Parameters affecting propulsion performances are analyzed using a one-dimensional (1-D) calculation method. The basic motion modes are obtained according to the analysis.