Design and Preliminary Evaluation of A Biomimetic Underwater Robot with Undulating Fin Propulsion

Abstract

Biomimetic undulating fin propulsion systems have the advantages for enhancing the maneuverability and efficiency of underwater robot when compared with conventional driving forms. However, there are still some defects existing in this approach, such as low speed and difficulty in depth control. This paper presents the mechanical design, control system design and experimental evaluation of a biomimetic underwater robot with undulating fin propulsion. First, a 3D model of the robot was established in CATIA. According to the kinematic model of the fins, the design of undulating fin propulsion system have been optimized and the phase control method has been proposed to fit with the design. Next, a control system with hybrid structure switching between autonomous mode and remote mode has been implemented to address the problem that the robot is out of control in underwater environment due to the attenuation of radio signals. Finally, the underwater locomotion performance of the robot has been validated in a swimming pool. The result indicates that the robot can achieve multiple degree of freedoms (DOFs) motions by controlling the kinematic parameters of the fin and was able to swim as fast as 31.6 cm/s (nearly 0.8 body length per second).