Development of a Small Drilling/Coring Machine for ROV to Get Cores at Multiple Places in One Dive

In sea-bottom drilling/coring, a big Boring Machine System on sea-bottom or a big on-board Boring Machine System is usually used. Such system requires a big ship and a specialized capability, and can get long cores, but it will take a long working duration for one core recovery, and hence it will be difficult to drill/core many points in short time for grasping the features of the targeted wide area. In order to cope with this situation, a new type drilling system has been developed and tested on a sea floor. This system is so small as to be carried and handled by work-class ROV and can drill/core at multiple places in one dive of ROV. This machine is handled by ROV's manipulator and can get short cores at an arbitrary angle set by the manipulator (see Fig. 1). While drilling, ROV can clearly watch the drilling and coring works without being disturbed by the cloud of dust. Also, this system can perform high-speed drilling/coring and the direction of the recovered core can be confirmed very easily. This system can be applied to various works such as wide area survey or grid survey utilizing high-speed and multiple drilling/coring capability, or paleomagnetic survey by orientation confirmation of the cores. This paper shows the mechanism of this new system and sea-trial results.