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Underwater Robotics [ April 2015 ~ Present ]

Research Background
3D Reconstruction of Underwater Environment Using Acoustuc Camera
In recent years, waterfront development, such as construction and reclamation projects related to airports, ports, and submarine tunnels, has become considerably more critical. To conduct such heavy work, there exist underwater construction machines operated by divers in an underwater environment. However, hazards may prohibit human access and the limited field of vision due to turbidity and lack of illumination makes underwater operations difficult. To complete tasks, such as inspection, removal of hazardous materials, or excavation work, a remote control robot equipped with a 3D system for reconstructing the underwater environment is required, as shown in Fig. 1.

Recently, the development of acoustic cameras, such as the dual frequency identification sonar (DIDSON) and adaptive resolution imaging sonar (ARIS), which can generate high-resolution and wide-range images, has facilitated our understanding of underwater situations. This type of sonar sensor is relatively small and can easily be mounted on an underwater robot and gather information of a relatively larger area considerably faster. The acoustic camera can also be mounted on an arm of a crawlertype robot, and thus, the robot can fulfill complex underwater tasks, such as manipulation, even in turbid water.

In this research, a novel dense 3D mapping paradigm for an acoustic camera in an underwater situation is proposed. As a result, it is possible to build a dense 3D map of the underwater environment precisely and robustly.

Fig. 1 Example of underwater construction using a remote control underwater crawler-type robot based on dense 3D mapping of surrounding environment using acoustic camera.
Related Paper
• Yusheng Wang, Yonghoon Ji, Hanwool Woo, Yusuke Tamura, Hiroshi Tsuchiya, Atsushi Yamashita, and Hajime Asama, "Rotation Estimation of Acoustic Camera Based on Illuminated Area in Acoustic Image," Proceedings of the 12th IFAC Conference on Marine Systems (CAMS2019), pp. 217-222, Daejon, Korea, September 2019.
• Yusheng Wang, Yonghoon Ji, Hanwool Woo, Yusuke Tamura, Atsushi Yamashita, and Hajime Asama, "Three-dimensional Underwater Environment Reconstruction with Graph Optimization Using Acoustic Camera," Proceedings of the 2019 IEEE/SICE International Symposium on System Integrations (SII2019), pp. 28-33, Paris, France, January 2019. [Link]
• Yusheng Wang, Yonghoon Ji, Hanwool Woo, Yusuke Tamura, Atsushi Yamashita, and Hajime Asama, "3D Occupancy Mapping Framework Based on Acoustic Camera in Underwater Environment," Proceedings of the 12th IFAC Symposium on Robot Control (SYROCO2018), pp. 1-7, Budapest, Hungary, August 2018. (IFAC PaperOnLine, Vol. 51, No. 22, pp. 324-339, August 2018) [Link]
• Ngoc Trung Mai, Yonghoon Ji, Hanwool Woo, Yusuke Tamura, Atsushi Yamashita, and Hajime Asama, "Acoustic Image Simulator Based on Active Sonar Model in Underwater Environment," Proceedings of the 15th International Conference on Ubiquitous Robots (UR2018), pp. 781-786, Hawaii, USA, June 2018. [Link]
• Ngoc Trung Mai, Hanwool Woo, Yonghoon Ji, Yusuke Tamura, Atsushi Yamashita, and Hajime Asama, "3D Reconstruction of Line Features Using Multi-view Acoustic Images in Underwater Environment," Proceedings of 2017 IEEE International Conference on Multisensor Fusion and Integration for Intelligent Systems (MFI2017), pp. 312-317, Daegu, Korea, November 2017. [Link]
• Ngoc Trung Mai, Hanwool Woo, Yonghoon Ji, Yusuke Tamura, Atsushi Yamashita, and Hajime Asama, "3-D Reconstruction of Underwater Object Based on Extended Kalman Filter by Using Acoustic Camera Images," Preprints of the 20th World Congress of the International Federation of Automatic Control, pp. 1066-1072, Toulouse, France, July 2017. (IFAC PaperOnLine, Vol. 50, No. 1, pp. 1043-1049, July 2017) [Link]
Yonghoon Ji, Seungchul Kwak, Atsushi Yamashita, and Hajime Asama, "Acoustic Camera-based 3D Measurement of Underwater Objects through Automated Extraction and Association of Feature Point," Proceedings of the 2016 IEEE International Conference on Multisensor Fusion and Integration for Intelligent Systems (MFI2016), pp. 224-230, Baden-Baden, Germany, September 2016. [Link]
• マイ ゴクチュン, 禹 ハンウル, 池 勇勳, 田村 雄介, 山下 淳, 淺間 一, "音響カメラ画像を用いた拡張カルマンフィルタに基づく水中物体の3次元計測手法の構築," 第34回日本ロボット学会学術講演会予稿集 (RSJ2016), RSJ2016AC1C3-06, pp. 1-4, 山形, September 2016.
• Seungchul Kwak, Yonghoon Ji, Atsushi Yamashita, and Hajime Asama, "3-D Reconstruction of Underwater Objects Using Arbitrary Acoustic Views," Proceedings of the 2016 11th France-Japan congress on Mechatronics 9th Europe-Asia congress on Mechatronics 17th International Conference on Research and Education in Mechatronics (MECHATRONICS-REM2016), pp. 74-79, Compiegne, France, June 2016. [Link]
• 곽 승철, 지 용훈, Atsushi Yamashita, and Hajime Asama, "다시점의 음향카메라 영상을 이용한 수중물체의 3차원 형상 복원," 2016 제31회 제어・로봇・시스템학회 학술대회, pp. 1-2, 서울, March 2016.
• Seungchul Kwak, Yonghoon Ji, Atsushi Yamashita, and Hajime Asama, "3-D Reconstruction of Underwater Object: Analytical System for Extracting Feature Points Using Two Different Acoustic Views," Proceedings of the 2015 JSME/RMD International Conference on Advanced Mechatronics (ICAM2015), pp.197-198, Tokyo, Japan, December 2015. [Link]
• 郭 承澈, 池 勇勳, 山下 淳, 淺間 一, "2視点における音響カメラ画像をを用いた水中物体の特徴点の3次元計測," 第33回日本ロボット学会学術講演会予稿集 (RSJ2015), pp. 1-4, 東京, September 2015.
• Seungchul Kwak, Yonghoon Ji, Atsushi Yamashita, and Hajime Asama, "Development of Acoustic Camera-Imaging Simulator Based on Novel Model," Proceedings of the 2015 IEEE International Conference on Environment and Electrical Engineering (EEEIC2015), pp. 1719-1724, Rome, Italy, June 2015. [Link]