Design and implementation of a robotic shark with a novel embedded vision system

Abstract

This paper focuses on the mechatronic design and control issues of a novel robotic shark with an embedded vision system. To pursue a better swimming performance, an updated robotic shark with more degrees of freedom (DOFs) is constructed. Specially, an optimized propulsive mechanism with three links is designed to fit a typical shark-like swimming and a pair of pectoral fins with two separate DOFs is employed to regulate both pitch and roll attitude. To strengthen the capability of underwater perception, an embedded vision system is imported. Besides, a particular camera stabilizer with an Inertial Measurement Unit (IMU) is designed to counteract the head swing for high-quality images. Moreover, a CPGs-governed control strategy is adopted to realize various shark-like motions and further analyses are executed to explore the relationship between propulsive performance and some key characteristics of adopted CPGs. Finally, the robotic shark successfully realizes more flexible shark-like locomotion containing forward swimming, turning, diving, and surfacing. The experimental results validate the effectiveness of the updated mechatronic design and adaptability of sharklike swimming governed by CPGs.