3D Motion Analysis and Implementation of a Developed Gliding Robotic Dolphin This paper investigates the threedimensional (3D) maneuverability of a gliding robotic dolphin through analyzing the horizontal and vertical motions. Concretely, in order to improve the performance in the horizontal plane, the gliding robotic dolphin is developed with a rudder installed on its belly, and the 3D fullstate dynamic model is derived briefly. By setting two typical body andor caudal fin (BCF)based and three typical median andor paired fin (MPF)based turning patterns, the turning performances are revealed and analyzed. With regard to the vertical plane, a novel finite state machine framework is proposed to realize the vertical downward action. Finally, extensive experiments involving the turning and vertical motions are conducted to illustrate and analyze the 3D maneuverability, which provides valuable guidance for the realworld applications of the gliding robotic dolphin.

Design and Yaw Control of a TwoMotorActuated Biomimetic Robotic Fish This paper addresses the design and control of a novel tunainspired robotic fish able to realize both fast swimming and high maneuverability. A twostage transmission mechanism is proposed, aiming at reducing the volume and mass of caudal peduncle. Benefited by it, both volumes and mass of moving parts can be reduced to allow higher swing frequency. At the same time, two joints driven by two motors ensure the flexibility of steering. The robotic fish achieves a maximum speed up to 1.65 body lengths per second (BLs) and a minimum turning radius less than 0.35 body lengths (BL), based on the openloop control designed by Central Pattern Generator (CPG) method. Furthermore, a yaw control is proposed to maintain course angle at high swimming speed, and simulation in Automatic Dynamic Analysis of Mechanical Systems (ADAMS) software reveals the effectiveness. The results show that the proposed yaw control method can regulate the fluctuation of anterior body to desired range but without compensation of sideways drift.