Development of a Novel Robotic Dolphin and Its Application to Water Quality Monitoring

This paper presents the mechatronic design and hydrodynamic analysis of a novel bioinspired robotic dolphin used for mobile water quality monitoring. A complementary configuration for mimicry of dolphin-like propulsion is first presented, involving a waist-fluke propulsive unit for dorsoventral oscillations and a pair of flippers with separate degree of freedom for three-dimensional (3-D) maneuvers. A host of onboard sensors is equipped to strengthen the capability of environment perception and mission execution on a near real-time basis. Considering the dynamic requirement for motion transition in water quality monitoring, a central pattern generator based controller is then built to govern the multimodal locomotion of the robotic dolphin. Moreover, a 3-D dynamic model based on the Lagrange method is employed to predict the propulsive performance, followed by simulations of continuous diving and surfacing motions. Finally, both laboratory and field experiments are conducted to demonstrate the effectiveness of the presented mechatronic design and control methods. The results further show that the robotic dolphin with 3-D maneuverability offers a feasible solution to aquatic mobile sensing.