This study proposes an underwater walking mechanism for an underwater amphibious robot that is propelled by a degree of freedom flapping foil system. To implement stable walking in water, we proposed a distinctive hinged multi-modal paddle and developed an underwater amphibious robot. For the proposed paddle, forward walking model is proposed regarding both the ground contact and hydrodynamic forces in each walking phase: the stance and swing phases. Then, we generalized dynamic equations of motion for the amphibious robot based on the forward walking model. The proposed mechanism and robot were evaluated through thrust and forward walking tests in an indoor water tank. The results of the forward walking test exhibited a highly accurate trajectory of legged locomotion compared to the model-based simulation results. Moreover, field tests on gravel and soft terrains of a seabed, revealed that the proposed system allowed the amphibious robot to walk qualitatively.

中文翻译：

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铰链式多模态桨水下两栖机器人水下行走机构

本研究提出了一种水下两栖机器人的水下行走机制，该机器人由自由度扑翼系统推动。为了实现水中的稳定行走，我们提出了一种独特的铰链多模态桨，并开发了一种水下两栖机器人。对于所提出的桨，提出了关于每个行走阶段的地面接触和水动力的前向行走模型：站立和摆动阶段。然后，我们基于前向行走模型推广了两栖机器人的运动动力学方程。通过在室内水箱中进行推力和向前行走测试，对所提出的机构和机器人进行了评估。与基于模型的模拟结果相比，前向行走测试的结果显示出高度准确的腿运动轨迹。而且，