Research on self-propelled performance of multi-body system of wave-driven robot

wave-driven robot is a flexible multi-body dynamic system driven by ocean waves. Self-propelled performance is an important index of wave-driven robot, which includes propulsion performance, resistance performance and rapidity of wave-driven robot, as well as its ability to capture and utilize ocean wave energy. However, the wave-driven robot belongs to flexible multi-body structure, whose dynamic model is more complex compared with conventional ocean vehicle, and the motion of wave-driven robot is completely driven by waves. It is difficult to predict its dynamic response and kinematic performance. In this paper, a numerical method is developed to solve the self-propelled process of wave-driven robot by coupling flexible multi-body dynamics and computational fluid dynamics. Firstly, the flexible multi-body dynamic model of the whole wave-driven robot is established. Secondly, the numerical flow field which can simulate regular waves is established. Finally, the dynamic model is combined with the numerical flow field, and the self-propelled process of the wave-driven robot is simulated by overlapping grid under typical wave parameters, and the propulsion performance, resistance performance and rapidity of wave-driven robot are analysed in depth. Through the test in water pool, it is found that the prediction accuracy of the velocity of float can reach 92.52%.