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ABSTRACT: The Japan Agency for Marine-earth Science and Technology is now developing an automatic bottom inspection and sampling mobile, ABISMO, which is a full depth rating remotely operated vehicle for conducting research at the deepest sea bottom, observing the area with a camera, and sampling the bottom layer.
OCEANS 2009 - EUROPE; 06/2009
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ABSTRACT: It is hard to negate the effects of ocean waves on synthetic aperture sonar that has to be operated in the ocean and many efforts to deal with ocean waves have been made. One of these efforts is motion compensation by calculating phase errors with a computer. But the synthetic aperture algorithm with motion compensation is heavy, and remains difficult to be executed on a real-time basis. Thus, a modified synthetic aperture algorithm is proposed in this paper. This algorithm, which is named a 1.5-dimensional algorithm, is in between a one-dimensional and two-dimensional algorithm. It synthesizes a virtual aperture about 10 times faster than other algorithms in a computer simulation. Copyright © 2009 John Wiley & Sons, Ltd.
International Journal of Adaptive Control and Signal Processing 04/2009; 24(2):142 - 148. · 0.91 Impact Factor
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ABSTRACT: There are concerns about the impact that global warming will have on our environment, and which will inevitably result in expanding deserts and rising water levels. AUVs (autonomous underwater vehicle) were considered and chosen, as the most suitable tool for conduction survey concerning these global environmental problems. JAMSTEC has started to build a long range cruising AUV. The plan for its development is in several steps. As the first step an AUV, named URASHIMA was built in 1999, and sea trials have been held since 2000. URASHIMA dived to 3,518 m depth in 2001. At the end of February 2005, the vehicle was able to cruise autonomously and continuously for 317 km. This paper describes outline of the vehicle, presents some experimental results.
Industrial Technology, 2009. ICIT 2009. IEEE International Conference on; 03/2009
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T Sawa, T Aoki,
M Nakamura,
H Yoshida,
S. Tsukioka,
H. Tadahiro,
S. Syoujiro,
A. Isikawa,
T. Kamakura,
S. Matusbara,
S. Wright
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ABSTRACT: It is hard to negate the effects of ocean waves on a synthetic aperture sonar that has to operate in the ocean, and many efforts against the ocean waves had been taken. One of the effort is motion compensation by calculating phase errors with computer. But the synthetic aperture algorithm with motion compensation is heavy, and remains difficult to be executed on real time. Thus, modified synthetic aperture algorithm is proposed in this paper. The algorithm, which is named 1.5-Dimensional algorithm, is in between 1-Dimensional and 2-Dimensional algorithm. The algorithm synthesizes an virtual aperture faster than the others, and has no phase error theoretically. The algorithm had been executed with raw sonar data acquired in a sea trial experimentally, and higher quality sonar images are generated successfully.
OCEANS 2008 - MTS/IEEE Kobe Techno-Ocean; 05/2008
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ABSTRACT: For studies and investigates about the ocean, various underwater vehicles are used. All these vehicles controlled by electronics. Electronic devices need solid pressure vessel to protect them from seawater and water pressure. For electronic devices using under water, defer from using in the air, they need solid pressure vessel. Particularly, water pressure is increasing according to depth, so the pressure vessels need to make strong. But strong vessels are very heavy weight. It is not good at treatment. Especially for long cruising vehicle that is worse about energy effect. If we can make pressure vessels and frames with lightweight and strong material, we can reduce weight of vehicles. And that help weight loss of buoyancy materials and the expansion of the payload. We start to development of new pressure vessel with magnesium alloy that specific gravity is light than titanium alloy and the aluminum alloy. Our development aim is stronger than Titanium (Ti-6Al-4V) at ratio of (tensile strength) by density. The Ti-6Al-4V is usually used light and strong material for pressure vessel. Our development target is 1.3 times stronger than Titanium alloy (Ti- 6Al-4V) at ratio of (tensile strength) by density as strength of a pressure vessel. The paper presents experiment results of the evaluations examination obtained by using specimens and a small pressure vessel made by Magnesium alloy.
OCEANS 2008 - MTS/IEEE Kobe Techno-Ocean; 05/2008
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ABSTRACT: Recently, a number of bacteria including new one have been found from mud samples of Challenger Deep in the Mariana Trench. In order to get those samples or the sediment core in there, an underwater vehicle, which can dive to the deepest ocean and carry out the task, is needed, however, currently, there is no such vehicle in the world. So Japan Agency for Marine-Earth Science and Technology (JAMSTEC) began developing a new ROV for the deepest ocean use in 2005, it is "ABISMO". In this paper, several main systems of ABISMO and results of sea trials carried out before now are shown, and the operation support system is described.
OCEANS 2008 - MTS/IEEE Kobe Techno-Ocean; 05/2008
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H. Yoshida, T. Aoki,
H. Osawa,
S. Tsukioka,
S. Ishibashi,
Y. Watanabe,
J. Tahara,
T. Miyazaki,
T. Hyakudome,
T. Sawa,
K. Itoh,
A. Ishikawa,
D. Lindsay
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ABSTRACT: JAMSTEC has developed the two types of underwater vehicle since 2005: an ROV to the oceans' deepest depth called ASSS11k (advanced sediment sampling system to 11,000 meter) and a hybrid underwater vehicle for use in shallow-water to mid-depth zones named PICASSO (Plankton Investigatory Collaborating Autonomous Survey System Operon). The most important purpose of the ASSS11k is to get a lot of mud sample of challenger deep in the Mariana Trench, because a number of bacteria have been found there. Scientist wants to continuously explore the deepest parts of the oceans with a vehicle equipped with sediment samplers. ASSS11k consists of a sampling station and a sediment probe. The station contains two types of bottom samplers. One launches the probe to make a preliminary survey, launching the sampler to obtain a sample. We carried out the first sea trial using support vessel of "KAIREI" in January 2007. We tested every functions of the system and achieved sediment sampling at Sagami bay. PICASSO (2 times 0.8 times 0.8 m, 200 kg) is designed for biological and oceanographic observations in depths of up to 1,000 m. This small, light vehicle can be handled and operated by a team of only a few people. The easy-to-use vehicle does not need a dedicated support ship. The vehicle can be used either as untethered remotely operated vehicle (UROV) or autonomous underwater vehicle (AUV). In order to develop these vehicles, we used some new technologies and then developed new original devices: a small electrical-optical hybrid communication system, an HDTV optical communication system with Ethernet interface, synthetic designed pressure vessel-chassis-inner circuit boards, buoyancy material for deepest depth, a thin cable with high-tensile strength, a core sampler launcher, crawlers, compact winch motor drivers, a USBL system, a ballast controller, a friendly-user-interface program for operator, a high capacity lithium ion battery, a down sizing optical fiber spooler, and a prototy-
pe of underwater electromagnetic communication system.
OCEANS 2007 - Europe; 07/2007
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ABSTRACT: An autonomous underwater vehicle (AUV) is equipped with an inertial navigation system (INS) in order to understand its own position in real time while it cruises without the communication with the external environment such as a support ship and GPS. Japan Agency for Marine-Earth Science and Technology has the cruising AUV URASHIMA, and it is also equipped with the INS. However the INS outputs its own absolute position containing the error that increases with time. It means, it is very difficult for URASHIMA to cruise dependent only on the position data outputted by the INS for a long time. So we have proposed the method to improve the performance of the INS, and its effect was confirmed in experiments. In the method, it was put on a turntable with assumption that it is fixed inside URASHIAM and the INS has been rotated by it around one rotation axis according to some rules. Consequently, the INS's position error was decreased by the rotational motion. In order to cause this effect, a precondition had to be met. It was that URASHIMA keeps its own posture to near-horizontal while cruising. However URASHIMA usually cruises with the roll motion which is caused by its shape. So the roll motion such as URASHIMA's one in a sea trial was applied to the turntable, and the INS was rotated in the situation. As the result, the INS's position error was decreased about half of the original one.
OCEANS 2007 - Europe; 07/2007
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ABSTRACT: The Independent Administrative Corporation Japan Agency for Marine-Earth Science and Technology (JAMSTEC) has been developing light-and-small autonomous underwater vehicles (AUV), named “Marine Robot Experimental 1” (“MR-X1”). In this paper, the motion control problem of “MR-X1” is considered. Since the dynamics of “MR-X1” depends upon its own speed, the problem in question becomes a non-linear control problem. A new controller design method using linear matrix inequalities (LMIs) is proposed in order to adapt the problem in question. The algorithm, which gives a solution of a linear matrix inequality (LMI), can adapt to solve numerous LMIs simultaneously. LMIs can be obtained by substituting several speeds into the dynamics of “MR-X1”. The proposed controller, which can be derived from the solution of LMIs, becomes a stabilizing controller for all substituted speeds.
International Journal of Control. 07/2007; 80(7):1125-1135.
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ABSTRACT: JAMSTEC has been developing the remotely operated vehicle system having a limited role to explore the deepest parts of the oceans since April 2005. This ROV system's main mission is to survey sediments in sea bottoms. This system consists of a launcher and a small vehicle. The launcher carries two types of bottom samplers as well as the vehicle. One launches the small vehicle to make a preliminary survey, launching the sampler to obtain a sample. The samplers can be changed a gravity core sampler for a grabber. The system assembly will be completed by the spring of 2006 and then its sea trials will be started.
OCEANS 2006 - Asia Pacific; 06/2007
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ABSTRACT: Recently, a number of bacteria have been found from a mud sample of Challenger Deep in the Mariana Trench. Sampling those sediment samples, an ROV to the oceans' deepest depth is needed. But no vehicle gets to the deepest depth in the world. Scientists want to continuously explore the deepest parts of the oceans with a vehicle equipped with sediment samplers. JAMSTEC started developing a sediment sampling system from April 2005. The system consists of a sampling station and a sediment probe. The station contains two types of bottom samplers. One launches the probe to make a preliminary survey, launching the sampler to obtain a sample. We carried out a sea trial on January 5-7, 2007 in Sagami Bay and was successfully completed. The ROV took a mud sample by using the gravity core sampler.
Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies, 2007. Symposium on; 05/2007
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ABSTRACT: An Autonomous Underwater Vehicle (AUV) is equipped with an Inertial Navigation System (INS) in order to detect its own current position for the autonomous cruise. It has a sensor part and an arithmetical part. The sensor part is composed of three gyros and three accelerometers, and the three-dimensional coordinate system (INS coordinate system) is defined in the arithmetical part. And an accelerometer and a gyro are set on each axis in the coordinate system. The INS calculates AUV's position using outputs of the sensors. So the position accuracy of it depends strongly on the precision of the sensors. However they have drift-bias errors which increase with the passage of the time. So, a method, which applies the rotational motion to the INS, is proposed in order to reduce the errors. In this method, the INS is put on the turntable and the INS is rotated by it around an axis of the INS coordinate system. And the errors of sensors, which are set on non-rotation axis, were reduced on average. This causes the position accuracy improvement. As the experimental results, the position error of the INS is reduced up to four times if suitable methods are given to it.
Underwater Technology and Workshop on Scientific Use of Submarine Cables and Related Technologies, 2007. Symposium on; 05/2007
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ABSTRACT: JAMSTEC has been developing AUVs: the cruising AUV "Urashima" and the working AUV "MR-X1". The cruising AUV is able to collect sea data and samples automatically in long range cruising. The working AUV which would be equipped with manipulators is also needed as alternated for ROVs. The MR-X1 is designed for the scientific work, such as installing or recovering observation equipment, tracking and sampling benthic feeders, and supporting ROV's works. We had started of development of the MR-X1 in 2000. Its body (2.5 m long, 800 kg weight) had been assembled by 2002. The control hardware using CAN bus interface was installed in 2003. Presently, we are mainly investigating the control system software. In this paper, we describe the system configurations of the MR-X1, focused on its control system. In addition, we report some results of sea trials.
OCEANS '04. MTTS/IEEE TECHNO-OCEAN '04; 12/2004
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ABSTRACT: Japan Agency for Marine-Earth Science and Technology (JAMSTEC) has advanced the development of an ocean going Autonomous Underwater Vehicle (AUV). Technical problem on an AUV is to develop instruments for highly accurate positioning, an efficient power source and digital telemetry in the sea. The AUV in JAMSTEC has accurate positioning system, fuel cell and digital telemetry. Sea test started in 2000, results were fed back to instruments to improve AUV performances. Its energy source was replaced to closed-cycle fuel cell system from lithium-ion battery in 2002. The AUV was successfully cruised 220 km range in 2003 along the pre-programmed route while having submerged. This paper presents result and navigational data obtained in a long distance test with the AUV
OCEANS '04. MTTS/IEEE TECHNO-OCEAN '04; 12/2004
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I. Yamamoto, T. Aoki,
S. Tsukioka,
H. Yoshida,
T. Hyakudome,
T. Sawa,
S. Ishibashi,
T. Inada,
K. Yokoyama,
T. Maeda,
S. lshiguro,
H. Hirayama,
K. Hirokawa,
A. Hashimoto,
N. Hisatome,
T. Tani
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ABSTRACT: JAMSTEC (Japan Agency for Marine-Earth Science and Technology) and MHI (Mitsubishi Heavy Industries, Ltd.) have been developing the AUV (Autonomous Underwater Vehicle) "Urashima" since 1998. Long-distance cruising AUVs generally need an AIP (Air Independent Propulsion) power source characterized by high-energy density and high-energy efficiency. Fuel cells are the preferred AIP power source for small underwater vehicles and PEFC (Polymer Electrolyte Fuel Cell) have been adopted for "Urashima". It is understood that one of the main themes with fuel cell is storing the hydrogen, the metal hydride storage has been adopted for "Urashima" as a safer method of storing the hydrogen. In summer of 2002 the AUV "Urashima" successfully completed an autonomous 132.5 km long-distance cruise using large capacity lithium-ion rechargeable battery. In the meantime, a Closed Cycle PEFC (Polymer Electrolyte Fuel Cell) system with a metal hydride hydrogen storage system was developed as an alternative AIP power source in order to extend "Urashima"'s cruising range. The lithium-ion rechargeable battery was replaced by the Closed Cycle PEFC system and this system became the main power source of "Urashima" in winter of 2002. "Urashima", with its new power source (the Closed Cycle PEFC system) achieved the world's first and deepest fuel cell power source dive in summer of 2003 and completed an autonomous cruise of 220 km in spring of 2004. In sea trials, the fuel cell system with metal hydride hydrogen storage system worked adequately and underwater fuel cell operation was verified. There were no problem in supplying power to the vehicle and supplying hydrogen to fuel cell system. "Urashima" will carry out the AUV world record 300 km cruising at upcoming trial opportunity.
OCEANS '04. MTTS/IEEE TECHNO-OCEAN '04; 12/2004
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S. Ishibashi, T. Aoki,
S. Tsukioka,
H. Yoshida,
T. Inada,
T. Kabeno,
T. Maeda,
K. Hirokawa,
K. Yokoyama,
T. Tani,
R. Sasamoto,
Y. Nasuno
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ABSTRACT: An ocean going autonomous underwater vehicle "URASHIMA" had its birth at Japan Marine Science and Technology Center (JAMSTEC) in 1998, aiming to obtain the solutions against various disorders occurring in the ocean and on the Earth, such as global warming, climate changes, earthquakes, volcanic activity and so on. "URASHIMA", which was equipped with a lithium-ion rechargeable battery and hardware and software, was improved gradually in the first development stage from 2000 to 2002. In 2003, as the second development stage, "URASHIMA" aiming at a longer cruise of 300 kilometers was equipped with a solid polymer electrolyte fuel cell (PEFC) as the electric power source instead of the lithium-ion rechargeable battery. In the near future, "URAHISMA" will achieve a cruise of over 300 kilometers and a challenging expedition under ice plates in the Arctic Sea and observe in various areas where ROVs and manned submersibles have not approached until now. We show key technologies and systems of URAHISMA, and report the successful results obtained until now.
Underwater Technology, 2004. UT '04. 2004 International Symposium on; 05/2004
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ABSTRACT: Since 2000, JAMSTEC has been developing an AUV (length: 2.5 m, weight in the air: 800 kg), MR-X1, with a shape like the head of a fish. The maximum depth of the AUV is 4,200 m and its operating time is approximately 15 hours with a Li-ion battery unit. Five thrusters are equipped for high maneuverability. A TV camera, a side scan sonar, and a manipulator are equipped for various scientific works. MR-X1 has three operation modes: an autonomous mode, an UROV mode, and a wireless (acoustic/radio) control mode. The development goal of the MR-X1 is achievement of the working robot with high intelligence for detailed ocean investigation, installation of observation equipment on the sea floor and so on.
OCEANS 2003. Proceedings; 10/2003
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ABSTRACT: Japan Marine Science and Technology Center (JAMSTEC) has advanced the development of an ocean going autonomous underwater vehicle (AUV). Technical problem on an AUV is to develop instruments for digital telemetry, highly accurate positioning in the sea and an efficient power source. The AUV in JAMSTEC has digital telemetry, accurate positioning system and high energy density battery. Sea test started in 2000, results were fed back to instruments to improve AUV performances. The quality of the communication has improved by the noise reduction. The positional error of the AUV was evaluated with a track given by an acoustic positioning system and DGPS on board a support vessel. The examination was planned and expanded based on previous results step by step. As the result, the AUV cruised more than 130km along the preprogrammed route while having submerged. This paper summarized the result of the sea area examination executed from 2000 to 2002.
OCEANS 2003. Proceedings; 10/2003
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ABSTRACT: The ROVs with thin cable system have been developed in JAMSTEC. The thin cable system is very convenient for AUVs, therefore it has been applied for the AUVs that have been developed in JAMSTEC. Conventional ROV systems need the thick cable to supply electric power from mother ship to under-sea vehicle. In the thin cable system, a thick cable is not necessary because a power source like a battery is installed in the vehicle. The communication between the vehicle and mother ship just needs to include observation data from vehicle and control data from mother ship. The data are communicated through only one optical fiber cable that is about 1 mm in diameter. The thin cable system is called "UROV system" in JAMSTEC. UROV system has some merits because of thin cable. First, since the optical fiber cable with the length of 10 km is installed in the small cylindrical case called "spooler", the onboard system is very compact against conventional ROVs. Second, if a tether cable gets entangled in something like under-sea structure, it is considered that a vehicle can not be recovered in worst case. In the case of UROV system, the vehicle can be recovered because it has safety sequence that will release the ballast for surfacing. UROV system has other merits. For example, there is no cable drag. UROV system is available not only ROV but also AUV. URASHIMA developed by JAMSTEC has 3 operation modes. UROV mode is one of these operation modes. This mode is mainly useful for debugging in early stage of developing. When troubles happen, it is difficult for normal AUV that has no cable to know the detailed state on real-time. In that case, in URASHIMA, UROV mode is very convenient debugging of software and hardware. Furthermore, URASHIMA can survey like ROV by optical communication for UROV mode, for example, to watch the TV image on real-time. This paper describes UROV system for 7,000 m class UROV, UROV7K, and AUV, URASHIMA.
OCEANS 2003. Proceedings; 10/2003
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ABSTRACT: A deep and long cruising range AUV (autonomous underwater vehicle) named "URASHIMA" (AUV-EXI; development code name), has been developed by JANISTEC since 1998. URASHIMA can cruise long distance in the sea and collect sea data and water samples automatically for offshore exploration. The dimensions and weight of URASHIMA are 10m (L), 1.3m (W), 1.5m (H), and about 7.5 tons in the air. There are two very important key technologies for a long cruising range autonomous underwater vehicle. One technology is the power source. URASHIMA has two types of power sources. One is a high capacity lithium-ion rechargeable battery. The other one is solid polymer electrolyte fuel cell. With these power sources the vehicle capable of performing long ranges missions. The estimated cruising ranges are about 100 km by using battery and about 300 km by using fuel cell each other at three knots. The other technology is the navigation system. The AUV cruises independently without any communications between the mother ship and vehicle. It is very important to know its present position and forward environment. URASHIMA has highly accurate navigation sensors, such that the inertial navigation system (INS) consists of three sets of ring laser gyro and accelerometers, obstacle avoidance sonar (OAS), Doppler velocity log (DVL) and acoustic homing sonar. The AUV enables long distance cruising independently with these navigation sensors. The sea-going tests started in June 2000. The equipment, hardware, software, and autonomous functions, will be improved gradually. In these sea trials, URASHIMA achieved a dive to3518 m and cruised 132.5 km in autonomous navigation mode.
OCEANS '02 MTS/IEEE; 11/2002
