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Development of a human-portable underwater robot for soil core sampling

This paper presents development and motion evaluation of a human-portable underwater robot for soil core sampling. The developed robot is a remotely operated vehicle (ROV) with a core sampling pipe. In general, core sampling devices are heavy and penetrate into the soil by their own weight. In contrast, the developed robot is lightweight and penetrates the soil by its thrust force. This robot has neutral buoyancy; it can therefore move to desired areas using its thrusters. As explained in this paper, we describe the robot specifications and present results of preliminary experiments for the motion performance. Experiments in a test tank demonstrate its static stability, vertical motion for core samplings, and other beneficial features. Moreover, field tests in a lake demonstrate the feasibility of the developed core sampling robot. The soil penetration depth was approximately 0.16 [m] in the first trial.