Control / Operation of Underwater Robot with Multi-jointed Dual-arm

In this research, we have developed a human-sized underwater robot (length; 700mm, diameter; 200mm) with two arms (total length; 600mm) instead of expert divers (Figure 1). One serial-linked arm has 5 DOF including 2 DOF of twisting/gripping of the hand. The single-handed operator we have developed can drive the arms/body simultaneously in this system (Figure 2). The mass of arms occupies 20% of the whole body weight so that the attitude of the robot may change during working. Movable flotation blocks keep/change the attitude to support the working, shifting the center of buoyancy with respect to the center of gravity (Figure 2, Figure 3). We have checked that this robot can work several underwater tasks instead of humans through field works (See movies).

Fig.1: Prototype (Coco)



Fig.2: Concept



Fig.3: Principle of changing the attitude by shifting movable flotation blocks

Movies

• Simultaneous operation of arm and body 1 (MPEG 5.7MB)

• Simultaneous operation of arm and body 2 (MPEG 5.0MB)

• Movable flotation blocks to keep pitch attitude (MPEG 3.4MB)

• Pitch attitude control using movable flotation blocks 1 (MPEG 5.0MB)

• Pitch attitude control using movable flotation blocks 2 (MPEG 3.2MB)

• Grasping a cup on bottom water 1 (MPEG 4.3MB)

• Grasping a cup on bottom water 2 (MPEG 3.6MB)

• Grasping the umbilical cable of the robot (MPEG 17.0MB)

Equipments

There are several experimental equipments for underwater robots in Ritsumeikan University.

• Experimental pool: Nano Biwa (5 x 5 x Depth 3m)
• SeaBotix-ROV: LBV150 x 2
• Pressure case (100m)

Fig.4: Nano Biwa


Fig.5: LBV150 (made by Seabotix)


Fig.6: Pressure case

Media

• COCO is introduced in exhibition on Internet, EXPO21.

Publications

• Mizuho Shibata, Takayuki Saito, Norimitsu Sakagami, and Sadao Kawamura, "Simultaneous Operation of Dual Arm and Body of Mobile Robots", The 2010 IEEE International Conference on Robotics and Biomimetics, accepted, 2010

• Norimitsu Sakagami, Takafumi Kanayama, Tomohiro Ueda, Hideki Hashizume, Mizuho Shibata, Sadao Kawamura, Hiroyuki Onishi, and Shigeo Murakami, "Design and Development of An Attitude Control System for a Human-sized ROV", The 11th International Conference on Control, Automation, Robotics and Vision, accepted, 2010

• Mizuho Shibata, Yuusuke Onishi, and Sadao Kawamura, "Experimental Evaluation of Flexible Joint Driven by Water Pressure for Underwater Robots", 2010 IEEE/RSJ International Conference on Intelligent Robots and Systems, pp.4011-4016, 2010

• Norimitsu SAKAGAMI, Mizuho SHIBATA, Hideki Hashizume, Yuuta HAGIWARA, Kouhei ISHIMARU, Tomohiro UEDA, Takayuki SAITOU, Kazuhiro FUJITA, Toshifumi INOUE, Hiroyuki ONISHI, Shigeo MURAKAMI, Sadao KAWAMURA, "Development of a Human-Sized ROV with Dual-Arm", Proc. MTS/IEEE Int. Conf. on OCEANS，2010

• Norimitsu Sakagami, Mizuho Shibata, Sadao Kawamura, Toshifumi Inoue, Hiroyuki Onishi and Shigeo Murakami, "An Attitude Control System for Underwater Vehicle-Manipulator Systems", Proc. IEEE Int. Conf. on Robotics and Automation, pp.1761-1767，2010

Budget

• This research is a project among Kawamura Lab. in Ritsumeikan Univ., Sakagami Lab. in Tokai Univ., and DAINIPPON SCREEN MFG. CO., LTD..

• This research has been partly supported by the fund of a Research for Promoting Technological Seeds in Japan Science and Technology Agency (No.1038, 2009).

• This research is partly supported by the Ocean Policy Research Foundation (2009-)