Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
SATORU YAMAGUCHI Last modified date:2024.06.27

Associate Professor / Marine Sytems Design / Department of Marine Systems Engineering / Faculty of Engineering


Papers
1. Yu Fukuda, Satoru Yamaguchi, Yuta Shindo, Investigation of the motion control performance and hydrodynamic of a multi-winged towed vehicle with intentional instability, Proceedings of the Thirty-third(2023) International Ocean and Polar Engineering Conference, 1824-1830, 2023.06, The authors propose a towed vehicle with intentional instability for use in seafloor exploration. This towed vehicle has one pair of canard wings in addition to conventional main and tail wings. The hydrodynamic characteristics and the motion control performance of the multi-winged towed vehicle with the three control surfaces are investigated. First, CFD and experiments were conducted to investigate the effects of interference between the wings. Then, equations of the motion for the multi-winged towed vehicle were formulated and the simulations of the motion control were conducted. The calculations were performed for the longitudinal motion of the vehicle. Since this system has three control inputs (three wing angles) for two control outputs (pitch and heave), the control input to reach the target is not uniquely determined. For this reason, the authors reduced the number of control inputs by linking the angles of the tail and the canard wings at a certain ratio. The motion control simulations confirmed that the pitch and heave can be controlled almost independently, demonstrating the superiority of the multi-winged towed vehicle over conventional ones..
2. Satoru Yamaguchi, Yu Fukuda, Yuta Shindo, Development of an Underwater Towed Exploration System for Archaeological Relics, Proceedings of the Thirty-second(2022) International Ocean and Polar Engineering Conference, 1200-1205, 2022.06, Many archaeological relics such as a wreck of an ancient ship are remains under the sea bottom and most of them are untouched because of difficulties of underwater exploration. Usual sub-bottom explorations for offshore resources such as oil and gas are carried out using seismic and sonic prospecting instruments and it is high cost and time consuming. On the other hand, archaeological relics in the relatively shallow water are explored by a sub-bottom profiler and by divers so the area which can be investigated is very limited.
The authors have been developing underwater towed vehicles and autonomous underwater gliders in the previous studies. These vehicles equip various types of instruments including an OBEM (Ocean Bottom Electro-Magnetometer). They are promising instruments for marine environment survey and ocean floor resources exploration.
In this report, a towed exploration system for archaeological relics exploration is proposed and the development of the vehicle including a motion controller is discussed. The vehicle is towed near the sea bottom to improve the accuracy of the measurement using a sonic prospector. The performance of the towed system and its motion control system are assessed by tank experiments and numerical simulations..
3. Nitin D. Thulkar, Satoru Yamaguchi, Hydrodynamic Forces of DP Jack-Up Leg when Operating in Vicinity of Seabed, Journal of Ship Research, J Ship Res 1–12.
Paper Number: SNAME-JSR-03200020, 2021.10, [URL], Leg placement and removal are the two most critical operational modes for dynamically positioned jack-ups when working close to an offshore asset. Any positional deviation may lead to collision and damage to the asset. The industry operates with a weak link between the dynamic positioning (DP) system and the jacking system. Current DP systems operate without any sensors identifying the hydrodynamic force variations on the legs and spudcans, which vary between different leg and spudcan designs. When the spudcan is near to the sea bottom, the hydrodynamic force must be reported to avoid large positional deviations driven by the DP system. This article promotes a mechanism to measure these forces using Computational Fluid Dynamics (CFD) analysis to analyze the jack-up behavior, when the spudcan assembly is operating close to the sea bottom..
4. Satoru Yamaguchi, Yutaro Miyai, Transient Motion Control of an Underwater Glider Based on Numerical Analysis, Proceedings of the Thirty-first (2021) International Ocean and Polar Engineering Conference, 283-288, 2021.06, The authors have been developing an autonomous underwater glider which equips an OBEM (Ocean Bottom Electro-Magnetometer). That is a hopeful instrument for the ocean floor resources explorations. The autonomous vehicle has an ability to achieve a continuous resource exploration autonomously for a long term. The motion control system for landing of the vehicle was investigated in the previous studies. In these reports, hydrodynamic performance of the vehicle in landing is examined by CFD calculations. The bottom effect which affects the lift and drag of the wings of the glider is studied and the characteristics of the blended wing body near a sea bottom is discussed.
On the other hand, the transient motions of the vehicle such as a deployment, the motion when the vehicle changes its buoyancy for cruise are also important problems for the motion control of the vehicle. The control system might be affected by the unpredicted change of the hydrodynamic forces acting on the body and the wing in the transient conditions. Consequently, it may cause deterioration of the performance of the control system.
In this report, these transient motions are investigated based on CFD analysis. The overset mesh approach is used to simulated the sequential maneuvers in the cruising of the underwater vehicle.
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5. Satoru Yamaguchi, Yutaro Miyai, Study on Hydrodynamic Performance of a Blended Wing Body for an Underwater Glider based on Numerical Analysis, Proceedings of the Thirtieth (2020) International Ocean and Polar Engineering Conference, 1222-1228, 2020.10, The authors have been developing an autonomous underwater glider which equips an OBEM (Ocean Bottom Electromagnetometer). That is a hopeful instrument for the ocean floor resources explorations. The autonomous vehicle has an ability to achieve a continuous resource exploration autonomously for a long term. The buoyancy and attitude control mechanism of the vehicle enable to move to the next measurement point by gliding.
The vehicle which has a blended wing body measures the slight variation of electromagnet wave on the sea bottom and the landing point for the measurement must be precisely controlled by the motion control system. In the landing stage, it is predicted that surface effect of the sea bottom affects the hydrodynamic characteristics of the vehicle, and it might cause some problems on the motion control system of the vehicle.
The authors attempt to make clear the characteristics of the flow field around the vehicle in the vicinity of a sea bottom. The motion control system for landing of the vehicle was investigated in the previous study (Yamaguchi and Sumoto, 2019). In this report, hydrodynamic performance of the vehicle in landing is examined by CFD calculations. The surface effect by a sea bottom which affects the lift and drag of the wings of the glider is studied and the characteristics of the blended wing body near a sea bottom is discussed..
6. Satoru Yamaguchi, Hirofumi Sumoto, Landing Motion Control of an Underwater Glider for Ocean Floor Resources Exploration, Proceedings of the Twenty-ninth (2019) International Ocean and Polar Engineering Conference, 1616-1621, 2019.06, Ocean floor resources such as sea-floor hydrothermal deposit, methane hydrate and manganese nodule are promising resources for future ocean development. It is becoming apparent by recent research that certain amount of these resources deposit also near Japan. Though several kinds of exploration methods such as seismic exploration, a multi-beam echo sounder and a sub-bottom profiler which are equipped with a survey ship are used for the resource explorations in general, these exploration methods need a large amount of cost and efforts.
On the other hand, an autonomous underwater glider which equips an OBEM (Ocean Bottom Electromagnetometer) which has been developed in the author’s laboratory is a hopeful instrument for the ocean floor resources explorations. The autonomous vehicle has an ability to achieve a continuous resource exploration autonomously for a long term. The buoyancy and attitude control mechanism enable the vehicle to move to the next measurement point by gliding.
The landing point for the measurement must be precisely controlled by the motion control system because the vehicle measures the slight variation of electromagnet wave on the sea bottom. The performance in a landing stage is essential for the motion control of the vehicle. Here, the motion control system of a weight shift device in the vehicle’s pressure container is developed for a landing stage. The authors attempt to make clear the performance of the controller in this report. Moreover, the characteristics of a buoyancy control device is examined by tank experiments. This unit is used to raise the vehicle to an appropriate height for the next gliding..
7. Nitin D Thulkar, Satoru Yamaguchi, Koki Ebihara, Study of Drag Force Acting on Various Types of DP Jack-up Vessel Legs, Proceedings of the Twenty-ninth (2019) International Ocean and Polar Engineering Conference, 2998-3004, 2019.06, The Dynamic Positioned (DP) Jack-up vessels currently use two popular designs of legs, (i.e. rack & chord lattices and cylindrical leg type). These two leg designs are popular and various experiment conducted in the past to evaluate the drag coefficient and drag force of these legs, but they are only available in a steady state condition. The intention of our experiment is to measure drag force and compare with CFD results. In DP vessels, mathematical model of the vessel first estimates the environmental force acting on the vessel, by using real time sensor data and then generate the counter balance thrust. The output command of force and angle is then sent to the available thrusters. However, usually, DP Jack-up vessels do not have sensor to measure the hydrodynamic force of leg &spudcan. Presently, each DP control system manufacturer for Jack-up vessels uses its own mathematical technique to achieve stability of station keeping during simultaneous operation of dynamic positioning and Jacking operation (SIMOPS). Moreover, this sensor less DP system tuning is unknown to the industries. Our intention of these experiments is to measure the hydrodynamic forces, in order to understand how the evaluated forces is altered under different environmental and operational conditions in SIMOPS operation. To start with, we first decided to measure drag forces when leg & spudcan moves in UP/DN direction under variable environment current. Both CFD and tank experiment is done using 3D prototype scale model of a cylindrical leg. The experimental limitation is also defined based on the tank facilities. The data is recorded during lowering and raising of the leg to see the effect on the drag force of leg- spudcan. The experimental data are recorded for current, leg speed; drag forces etc. with respect to time and average value considered for a steady state experimental case period. The evaluated results are compared with CFD results and show similar trends with acceptable error. The CFD analysis also carried out on a full-scale leg diameter to see the drag force trends. In order to understand the effect of seabed on the overall hydrodynamic force, cases were studied in which the leg was kept just a 0.1 m above seabed..
8. Satoru Yamaguchi, Landing Point Control of an Underwater Gliding Vehicle for Ocean Floor Resources Exploration, Proceedings of the 16th IAIN World Congress 2018, E4-2-E4-2, 2018.11, A novel exploration method for development of ocean floor resources such as sea-floor hydrothermal deposit, methane hydrate and manganese nodule is expected for effective utilization of the ocean resources.
The author has been developing underwater gliders for ocean floor resources exploration using an OBEM (Ocean Bottom Electromagnetometer). The vehicle has an ability to achieve long term continuous OBEM measurement autonomously. The vehicle is composed of a main wing for gliding and tail wings for landing point control for accurate observations. Buoyancy and center of gravity control devices, a battery, sensors and electric devices are contained in water tight vessels under the main wing.
The vehicle deployed by a research ship glides to the first observation point on the sea bottom. The vehicle measures the fluctuation of electromagnetic wave at the observation point after landing. Once the OBEM measurement at the first observation point is finished, the buoyancy of the vehicle is increased and the vehicle soars to an appropriate altitude. After that the buoyancy is decreased again and the vehicle glides to the next observation point. Repeating this procedure, the vehicle implements the autonomous OBEM measurement over a wide sea area.
In the successive measurements using OBEM, precise control of motion in landing is essential for safety operation and it is also important for accurate analysis of measured data in post process. In this report, motion control system of an underwater gliding vehicle for safety and precise landing is investigated. The motion equation of the vehicle and landing motion control method is explained. Numerical simulation results of landing operation of the underwater glider are also discussed..
9. Nitin Thulkar, Satoru Yamaguchi, Koki Ebihara, Analysis of Viscous Drag Forces on Jack Up Service Vessels during Simultaneous Operation, 日本船舶海洋工学会講演会論文集, 第27号, 339-341, 2018.11, The deepwater energy market in oil and gas has hampered, however the shallow water market continues to grow. Although the renewable energy impacting the energy market but it is mainly affecting coal based thermal power plants, while oil & gas energy market continue to grow.
The purpose of this manuscript is to find the viscous drag force on DP Jackup vessel during SIMOPS operation. The DP system calculates leg interaction forces using fixed Cd Value and fed to DP system for thrust calculation during this SIMOPS (i.e. Jacking operation+ DP station keeping).
However, during the CFD analysis, it was concluded that Cd values varies during leg transient from higher Cd value to steady state..
10. Satoru Yamaguchi, Sumoto Hirofumi, Ryota Sakamoto Ryo Nogami, Gliding Performance of an Underwater Glider for Ocean Floor Resources Exploration, Proceedings of the Twenty-eighth(2018) International Offshore and Polar Engineering Conference, 405-409, 2018.06, A novel exploration method of ocean floor resources is expected for effective utilization of the ocean and the object area for the development expands to deeper sea area recently.
An autonomous underwater glider which equips an OBEM (Ocean Bottom Electromagnetometer) for ocean floor resources explorations is proposed in this report. The autonomous vehicle has an ability to achieve a long term continuous resources exploration autonomously. The buoyancy and attitude control mechanism enable the vehicle to move to the next measurement point by gliding. The landing point for the measurement is precisely controlled by the motion control system.
The gliding performance of the vehicle is investigated by tank and field experiments. The mathematical model of the vehicle motion is refined based on the study and numerical calculations are carried out to design the motion control system for the autonomous underwater glider for OBEM measurement..
11. Nitin D Thulkar, Satoru Yamaguchi, Evaluation of Drag Coefficient Variation in Transit Mode on Leg & Spud can of DP Jackups Vessel, Proceedings of the Twenty-eighth(2018) International Offshore and Polar Engineering Conference, 1314-1321, 2018.06, The Marine and Oil & Gas industries have increased interest in Self Propelled DP Jackups vessel to enhance the overall operational efficiency. The self-propelled jackups vessel has numerous applications such as well intervention, wind farm installation, repair, accommodation, service etc. in this cost optimization process. However due to closed proximity of operation (i.e. near to hydrocarbon platforms or other offshore assets), it has gigantic risk during the Simops Operation.
The Simops Operation of Dynamic positioning and Jacking operation has a grey area in force calculations for DP system on board which use mathematical model. The input from position reference sensors, environmental sensors to calculate relative position based on position, heading, speed and rate of turn inputs for station keeping/ DP intended operation and finally issue thrust output command. The system continues to monitor the position by taking its feedback and comparing with calculated vessel position. However, many DP jackups does not have system for hydrodynamic force measurement of leg & spudcan. This is mainly due to drag coefficient of complex leg and Spud Can geometry. The drag coefficient plays vital role in force calculation and due to non-standard shape currently industries follow approximation method. This will increase risk in station keeping under different condition and failure cases.
The intension of this study is to find the gap in existing force calculation, which is affected by drag coefficient. During the CFD analysis evaluation the effect of marine growth, leg shape, spud can, leg transit speed under variable environmental conditions are considered. The software use for CFD analysis is Ansys Aim. The vessel data used for the simulation purpose are from most popular design of jackups vessel used in offshore O&G and wind farm industry.
The study will provide drag coefficient variation in transit time domain, which has large impact on force calculation estimation for DP System..
12. Satoru Yamaguchi, Sumoto Hirofumi, Taishiro Katsu, Yasushi Kono, Development of an Autonomous OBEM Measurement Vehicle for Offshore Resources Exploration, Proceedings of the Twenty-seventh(2017) International Offshore and Polar Engineering Conference, 326-330, 2017.06.
13. Shinpei Fujiwara, Satoru Yamaguchi, Fishlike Robot that Imitates Carangiform and Subcarangiform Swimming Motions, Journal of Aero Aqua Bio-mechanisms, Vol. 6, No. 1, 1-8, 2017.02.
14. Shinpei Fujiwara, Satoru Yamaguchi, Development and Performance Evaluation of Fish-Type Robot using Artificial Muscles and Servo Motors as Actuators, Journal of Aero Aqua Bio-mechanisms, Vol. 5, No. 1, 10-17, 2016.11.
15. Satoru Yamaguchi, Hideki MIZUNAGA, Taishiro Katsu, Satoshi Nakamuta, Yasushi Kono, Preliminary Design of an Underwater Glider for Ocean Floor Resources Exploration, Proceedings of the Twenty-sixth(2016) International Offshore and Polar Engineering Conference, pp.590-594, 2016.06.
16. Masaki Ishiguro, Akiji Shinkai, Satoru Yamaguchi, A Study on the Statistical Prediction of the Freak Wave Generation in the Ocean, Proceedings of the Twenty-third(2013) International Offshore and Polar Engineering Conference, pp.807-814, 2013.06.
17. Akiji Shinkai, Satoru Yamaguchi, Masaki Ishiguro, Shinji Yamada, A Study from a View Point of the Theory of Error about the Evaluation of Ship Design, Proceedings of 5th PAAMES and AMEC 2012, pp.1-6, 2012.12.
18. 山口 悟, A Study on IT Solution for Ship Design Based on Virtual Ship Concept, Proceedings of the Twenty-second(2012) International Offshore and Polar Engineering Conference, pp.944-951, 2012.06.
19. Sushant Godghate, Satoru Yamaguchi, A Study on Estimation of Ship Construction Based on Virtual Ship Concept, 日本船舶海洋工学会講演会論文集, 第14号 pp.399-402, 2012.05.
20. Hirofumi Sumoto and Satoru Yamaguchi, A Study on a Control Method of Artificial Muscle Using Segmented Binary Control for an Up-scaled Fish Type Robot, Proceedings of the Twenty-first (2011) International Offshore and Polar Engineering Conference, pp.223-229, 2011.06.
21. Hirofumi Sumoto and Satoru Yamaguchi, Development of a Motion Control System Using Phototaxis for a Fish Type Robot, Proceedings of the Twentieth (2010) International Offshore and Polar Engineering Conference, pp.307-310, 2010.06.
22. Akiji Shinkai, Satoru Yamaguchi, Yusuke Kuchiki and Naoto Kumamoto, Mathematical Logic for the Ship Design through the Axiomatic Approach, Proceedings of the Nineteenth (2009) International Offshore and Polar Engineering Conference, pp.764-770, 2009.06.
23. Masashi Terada, Hirofumi Sumoto and Satoru Yamaguchi, Development of Control System for a Fish Type Robot, Proceedings of the Nineteenth (2009) International Offshore and Polar Engineering Conference, pp.742-746, 2009.06.
24. Takashi Naito, Satoru Yamaguchi, Yuki Kawashita and Yoshikazu Fuchigami, Development of an Underwater Gliding Vehicle, Proceedings of the 3rd Pan Asian Association of Maritime Engineering Societies and Advanced Maritime Engineering Conference 2008, pp.633-638, 2008.10.
25. Satoru Yamaguchi, Tetsuya Toda, Seung-Jin Shin and Akiji Shinkai, On a Hull-Body displaying Method of Small High-Speed Boart in consideration of the Analysis of Spray around Bow, Proceedings of the 3rd Pan Asian Association of Maritime Engineering Societies and Advanced Maritime Engineering Conference 2008, pp.507-514, 2008.10.
26. Akiji Shinkai, Satoru Yamaguchi, Shinichiro Kashiwa and Daiki Kawashima, The Long-term Wave Statistics Database on the Pacific, Atlantic and Indian Oceans, Proceedings of the 3rd Pan Asian Association of Maritime Engineering Societies and Advanced Maritime Engineering Conference 2008, pp.473-480, 2008.10.
27. Masashi Terada, Hirofumi Sumoto and Satoru Yamaguchi, A Study on Characteristics of a Flexible Body for a Fish Type Robot, Proceedings of the Eighteenth (2008) International Offshore and Polar Engineering Conference, pp.377-381, 2008.07.
28. Satoru Yamaguchi, Takashi Naito, Takeshi Kugimiya, Kengo Akahosi and Masataka Fujimoto, Development of a Motion Control System for Underwater Gliding Vehicle, Proceedings of the Seventeenth(2007) International Offshore and Polar Engineering Conference, pp.1115-1120, 2007.07.
29. Satoru YAMAGUCHI and Masashi TERADA, A Study on Control Method for a Fish Type Robot by Artificial Muscle, The Proc. of the 16th Int. Offshore and Polar Engineering Conf., pp.254-259, 2006.06.
30. Seun-Jin SHIN, Satoru YAMAGUCHI and Akiji SHINKAI, An Analysis of Spray for a Small High-Speed Craft by Jet of Water, The Proc. of the 16th Int. Offshore and Polar Engineering Conf., pp.509-513, 2006.06.
31. T Yokobiki, W Koterayama, S Yamaguchi, M Nakamura, Dynamics and control of a towed vehicle in transient mode, INTERNATIONAL JOURNAL OF OFFSHORE AND POLAR ENGINEERING, 10, 1, 19-25, 2000.03, The dynamics and control of a towed vehicle when it changes depth and course were studied theoretically and experimentally. A mathematical model of motions of the vehicle is described in 6-degree-freedom motion equations and that of the towing cable is done using the lumped mass model. Control systems based on an optimal control theory (LQI synthesis) were developed to control the vehicle safely during the depth change. In the course change experiment the pin controller was used. The performance of the controller and the accuracy of the mathematical model of motions have been evaluated by field experiments. The towing tension was also measured in field experiments to confirm the safety of the towing table..
32. W Koterayama, S Yamaguchi, T Yokobiki, JH Yoon, H Hase, Space-continuous measurements on ocean current and chemical properties with the intelligent towed vehicle "Flying Fish", IEEE JOURNAL OF OCEANIC ENGINEERING, 10.1109/48.820745, 25, 1, 130-138, 2000.01, A research project to develop observation systems for heat, momentum, and material circulation in the ocean and atmosphere was carried out by the Research Institute for Applied Mechanics, Kyushu University, from 1992 to 1997, A pitch, roll, and depth controllable towed vehicle called "Flying Fish" was developed which houses an acoustic Doppler current profiler, CO2 analyzer, and sensors for measuring temperature, salinity, dissolved oxygen, pH, turbidity, and chlorophyll. The length of the vehicle is 3.84 m, the breadth is 2.26 m, the height is 1.4 m, the weight in air is 1400 kg, and the weight in water is roughly 0 kg.
Flying Fish enables us to obtain space-continuous data of physical and chemical properties efficiently in the upper mixed layer of the ocean. From 1994 to 1997, the vehicle was used for observations in the northern, southern, and central parts of the Japan Sea in a collaborative study by Japan, Korea, and Russia. Examples of data obtained are shown in this paper and the results of current velocities are compared with those taken by other observation systems..