Search

The Japan Agency for Marine-Earth Science and Technology (JAMSTEC) developed the full depth ROV (remotely operated vehicle) UROV11K system. UROV system employed a single microfiber optic cable of 1 mm diameter to carry data telemetry and real time video images. The full depth ROV UROV11K system consists of newly developed full depth vehicle and ABISMO launcher. ABISMO launcher employed a primary cable of ROV KAIKO system. Total 20 km optic fiber cable stored by each spooler was mounted on the vehicle and ABISMO launcher. UROV11K system was designed to perform the scientific surveys at the full depth of 11,000 m. UROV11K sea trial was conducted in May 14, 2017 from the R/V Kairei in Mariana Trench, where the vehicle successfully performed scientific observation with real time 4K video camera images at full depth of 10,899 m. This paper describes an overview of the full depth ROV UROV11K system, advanced elements technologies and the sea trial result.

Bringing together state-of-the-art high-performance computing, remote sensing and spatial information sciences, we established a real-time tsunami inundation forecasting, damage estimation and mapping system to enhance disaster response. Using Tohoku University's vector supercomputer SX-ACE, we accomplished “10-10-10 challenge”, to complete tsunami source determination in 10 minutes, tsunami inundation modeling and mapping impacts in 10 minutes with 10 m grid resolution. Given the maximum flow depth distribution, we perform quantitative estimation of exposed population using census data, and the numbers of damaged structures by applying tsunami fragility curves. After the potential tsunami-affected areas and structural damage are estimated, the analysis gets focused and moves on to the “verification” phase using remote sensing. A semi-automated method to detect building damage in the tsunami-affected areas is developed using high-resolution SAR (Synthetic Aperture Radar) data so that the simulated results are verified and obtain a feedback to improve the accuracy of tsunami inundation forecasting.

Japan Agency for Marine Earth Science and Technology (JAMSTEC) has started a new project “submarine resource research project” in April 2011. We decided to advance the development of work class ROV “KAIKO Mk-IV” as fourth KAIKO's vehicle applied for submarine resource exploration. “KAIKO Mk-IV” construction started in April 2011 and it completed in March 2013. Then, its sea trials have been carried out in FY2013-FY2015. This paper describes about the development of new ROV (vehicle) “KAIKO Mk-IV” and those equipment using advanced technologies and test results.

It is possible to accurately recognize the shape of an object or to grip it by setting soft tactile sensors on a robot's hands. We studied a multichannel soft tactile sensor as an artificial hand and evaluated the pressure's response performance from several directions and the slipping and sliding responses. The tactile sensor consisted of multiple pneumatic sensors and a soft cap with a fingerprint structure that was made of silicone gum and was separated from multiple spaces. Evaluation tests showed that the multiple soft tactile sensors estimate both an object's contact force and its contact location. Our tactile sensor also measured the object's roughness by the slide on surface texture.

We present a method of resolving a fine structure in a magnetic susceptibility map, which cannot be distinguished by the conventional method, by using a densely sampled dipole field and by expanding a magnetic field perturbation map. We investigate effects of a sampling density of the dipole field on the spatial resolution and on obtained susceptibility values. When the sampling density is increased, a shape of an otherwise undistinguishable fine structure recovers gradually in an obtained susceptibility map. Furthermore, a peak susceptibility value of the fine structure is slowly getting closer to the correct values.

The electrical performance of a glass-type space solar sheet (G-SSS) was demonstrated in space. G-SSS comprises InGaP/GaAs dual-junction and InGaP/GaAs/InGaAs triple-junction solar cells. It is lightweight solar generation sheet, less than 0.5mm thick. It is mounted on the “HISAKI” (SPRINT-A) small scientific satellite, which was launched on September 14, 2013. The initial flight data were successfully acquired and this flight demonstration was a world-first experiment for G-SSS using III–V multi-junction thin-film solar cells. The cells demonstrated superior performance and the electrical outputs matched the flight prediction.

Performing oceanographic measurements from the sea surface to the sea bottom is technically challenging under rough or icy sea conditions. In 2011, we tested measures for protecting a buoy under such severe conditions, by incorporating anti-icing and tolerance to high winds and rough seas. Based on the results, we carried out detailed designs of a suitable buoy system. In January 2012, we succeeded in deploying the buoy in the Southern Ocean off the Adelie Coast at 60°S and 140°E. Some of the meteorological and oceanographic data being gathered by the buoy can now be monitored in real time. In this paper, we describe some details concerning the design of the sensor pole and mooring line, in addition to the data already received from the buoy.

Performing oceanographic measurements from the sea surface to the sea bottom is technically challenging under rough or icy sea conditions. As a measure to deal with rough seas, a new dynamic simulation program was developed and its validity was verified by comparison with the results of actual sea tests. This program can therefore be used as a design tool. To develop countermeasures against icing, we carried out basic tests in a large-scale snow and ice laboratory. Some of these countermeasures were then implemented in real sea tests and were found to be effective under icy conditions. These results indicate that deployment of moored surface buoys in regions of rough and icy sea conditions will soon be practical.

11,000m class ROV, KAIKO, was developed in 1995 and dived to the seabed of 11,000m depth at Challenger Deep in Mariana Trench about 20 times (Fig.1). In March, 1996, KAIKO was sampling almost 20ml of sediment at Challenger Deep (10,897m depth). Many microbe in deep sea like extreme environments have been found in it, and their life have been cleared by the little sediment sample. So, it is necessary to collect much sediment sample at Challenger Deep to progress the research. But, the vehicle of KAIKO has been lost in May, 2003, because the secondary cable connecting the launcher and vehicle was snapped. The research of extremophiles in deep sea has been interrupted. Therefore, JAMSTEC has developed 11,000m class free fall mooring system in order to take the image and sediment sampling.

Ocean radars are installed on the ground to observe the current and waves on a wide area recently. About 50 ocean radars have been installed in Japan. The current and waves have been monitored primarily by various research institutes of universities and Ministry of Land, Infrastructure and Transport (MLIT) of Japan. The result of observation by ocean radars in the enclosed sea (Tokyo Bay Ise Bay Osaka Bay and Ariake Sea) and open sea (Kuroshio and Tsushima Current) has been provided to the public through the Internet. In enclosed sea areas, short and medium range-radars using 24 and 42 MHz, respectively, are installed. The long-range radars using 5-13 MHz are installed in the open sea. This paper introduces present and future of ocean radar in Japan based on the result of technical development by MLIT and the knowledge obtained through our research and development of ocean radars.

Deep manned submersible ldquoSHINKAI 6500rdquo was built in 1989, and has been operated by Japan Agency for Marine-Earth Science and Technology (JAMSTEC). She has capability to dive down to 6500 m depth. Currently, she made 1097 dives until the end of July 2008. A round hatch on the top of the pressure hull is designed to constitute a part of the spherical pressure hull, and is very important structure to keep atmospheric pressure and waterproof in the hull. Therefore, we handle a hatch carefully in every operation, and moreover, we remove a hatch from the pressure hull at the time of the annual-maintenance and are doing the careful overhaul which involves the measurement and exchange of components. The number of her diving exceeded 1000 times, and she will reach 20 years old shortly. As consideration for that, an operation team, an engineering division and a ship builder implemented investigation for reconfirmation about soundness and safety of the pressure hull including a hatch. In this report, the result of investigation and evaluation about behavior of a hatch including the pressure hull is described.

This paper proposes low complexity real-time video transcoders for video upload and retrieval applications. The proposed transcoders consist of both picture type conversion and syntax conversion in the compressed domain, and can highly reduce the computation amount in comparison with that of the conventional tandem transcoding method, in which decoding and re-encoding are necessary. The proposed syntax conversion can provide loss-less conversion, while the conventional tandem method is lossy conversion. Timestamp adjustment method is also proposed to avoid audio visual de-synchronization problem due to picture type conversion, when the stream is transmitted via constant bandwidth network. Complexity evaluation results based on DSP implementation confirm that the complexity of the proposed transcoders is very low and is less than 1/3 of that of the conventional tandem transcoder.

The remotely operated vehicle (ROV) Kaiko, built in 1995, is able to dive at ocean depths of 11,000 m. On May 29, 2003. the Kaiko's secondary cable snapped, and the Kaiko's vehicle has been missing. JAMSTEC (Japan Agency for Marine-Earth Science and Technology) was decided to remodel the 7,000 m class ROV UROV7K instead of the lost vehicle in order to continue the scientific activities. This system was called "KAIKO7000" system, and remodeling was finished in March 2004. After success of the sea trials, actual science activities that were interrupted by the Kaiko's vehicle lost was resumed in May 2005. JAMSTEC planed that over 10,000 m deep segment sampling in the Challenger Deep at the Mariana Trench by using the launcher system of "Kaiko". On December 10, 2006, we are carried out the sea trial for the segment sampling in the Challenger Deep at the Mariana Trench by using the launcher system of Kaiko. The launcher reached the depth of 10,131 m of the sea bottom at the Challenger Deep, and the core sampler "Asyura" succeeded in segment sampling. This paper describes about the method of deep-sea sediment sampling and the sea trial in the Challenger Deep at the Mariana Trench by using the launcher system of Kaiko.

We have been applying Taguchi Methods to important processes of semiconductor wafer. We review a couple of cases and then show how these methods can help us improve the key processes efficiently.

A noise tolerant auto-correlation associative memory is proposed. An associated energy function is formed by a multiplication of plural Hopfield energy functions each of which includes a single pattern as its energy minimum. An asynchronous optimizing algorithm of the whole energy function is also presented based on the binary neuron model. The advantages of this new associative memory are that the orthogonality relation among patterns does not need to be satisfied and each stored pattern has a large basin around itself. The numerical simulations show a fairly good performance of associative memory for arbitrary pattern vectors which are not orthogonal to each other.

The Hard X-ray Detector (HXD-II) is one of the scientific payloads on board the fifth Japanese cosmic X-ray satellite Asrto-E2, scheduled for launch in 2005. The HXD-II is designed to cover a wide energy range of 10-600 keV with a high sensitivity of /spl sim/ 10/sup -5/ cnt/s/cm/sup 2//keV, using 16 identical GSO and BGO phoswich counters combined with 2 mm-thick silicon PIN diodes. In order to investigate the in-orbit performance of HXD-II in cosmic radiation environment, a Monte Carlo simulator based on the Geant4 toolkit is currently developed. There are two main goals of this simulator, which is directly connected to the detector's performance. One is to derive energy response to photons within the acceptance energy range, with 5% accuracy, after several types of standard event-selection of the HXD-II. The other is to estimate detector background with 10% accuracy. In addition to the background caused directly by the primary and secondary cosmic-rays, of particular importance is the radio-activation background induced by MeV protons trapped in the South Atlantic Anomaly. The simulator is also used in the pre-launch verifications of the HXD-II hardware. This paper describes the design concept of the Monte Carlo simulator, and its verification through comparison with the actual data of pre-flight radio-isotope irradiation experiments, together with calculated outputs that can demonstrate the in-orbit performance of the HXD-II.

On May 29th, 2003, 10000 m class ROV KAIKO cruised for research mission in Nankai Trough at the southeast of 130km off Cape Muroto in Kochi prefecture. After completing the research mission at a depth of 4675 m, the vehicle of KAIKO has been missing because the secondary cable connecting the launcher and vehicle was snapped. Immediately, the vehicle has been searched from surface and air but it could not find. JAMSTEC has planned to remodel the 7000m class thin cable system ROV UROV7K as a replacement of the KAIKO vehicle, though operation depth and kinematical performance of it are lower than KAIKO vehicle. And JAMSTEC would use it temporarily for deep sea research, until new KAIKO system would be built. The system with KAIKO launcher and remodeled UROV7K is called KAIKO7000. UROV7K had the battery for power source and it was linked with the support vessel using a fiber optic cable of 1mm in diameter. It was developed for the missions of monitoring deep sea mooring systems and to survey deep seafloor. Some parts of UROV7K have been remodeled for replacement of the KAIKO vehicle. Main remodeling points were power supply system, increasing thrust and communication line. Furthermore, the safety measures pointed out by the Committee for the Investigation of Accident, have been included, too. KAIKO7000 has been finished remodeling in March, 2004, and the sea trials have been started in April, 2004. This paper describes about remodeling of KAIKO7000.

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.

An AUV goes along a pre-programmed route depending on the INS position; it is useful to watch the vehicle status and give commands correcting position error or alternating control mode by the existing state from a surface vessel in test phases. The AUV system has a digital acoustic communication system, capable of 4100 m maximum range in duplex. The communication range is shorter because the acoustic signal to noise ratio decreases at the AUV when a vertical thruster is operated. Noise is caused by reduction gear in the thruster unit. The reduction gear is improved to decrease the noise. The communication range is enhanced 2.5 times compared to previously, even if the thruster is operated in the sea. This article describes an investigation of low noise reduction gear for the acoustic down-link and test results.

It is thought that two dimensional resolution improvement of frame images is same as the problem of optimum search that satisfied a given condition to the frame imaging system. It is known that a genetic algorithm is extremely effective for optimum search problems. In this paper, a genetic algorithm is investigated for two dimensional resolution improvement of frame images in time series. Also, some experimental results are shown, and it is proved that the proposed method is effective when used with noisy images.

A novel DWDM spectrum design for millimeter-wave-band fiber-radio signals with square-like response fiber Bragg grating (FBG) filters is proposed. Error-free DWDM transmission of 60.0-GHz, 155.52Mb/s-DPSK fiber-radio signals with the specially prepared FBGs is experimentally demonstrated.

The topology preservation of self-organizing feature maps is an important property which is used in many applications. Various qualitative and quantitative approaches are known for measuring the degree of topology preservation. However, well-received measures for determining the topology preservation have not been presented yet. In this paper, we present a new method for measuring the degree of topology preservation based on the masked Delaunay triangulation. The topology preservation is completed when the masked Delaunay triangulation coincides with the output network shape. We demonstrate the usefulness of this measure for various examples of data manifolds. This method is also applied to measure the degree of topology preservation of the topology-representing network of T. Martinetz et al. (1994). In various simulations, this measure brought a reasonable degree of topology preservation.

With the increase of senior citizens, there is a growing demand for human-friendly wheelchairs as mobility aids. The paper proposes the concept of a robotic wheelchair to meet this need. It has three motion control modes. One is an autonomous control mode. The wheelchair has autonomous navigation capabilities, such as avoiding obstacles and moving straight toward a target object or along a corridor using ultrasonic and vision sensors. Another is a manual control mode with minimum intentional operations. The wheelchair observes the user's face by vision, moving in the direction indicated by the use's face movements. The third is a remote control mode. When the user is not riding, it can find him/her using face recognition. The user can make it come or go by hand gestures. We have developed an experimental robotic wheelchair based on the above concept. Experimental results prove our approach promising.

This paper proposes a wideband multi-rate speech and channel codec based on the MPEG-4/CELP for the ETSI/GSM full-rate channel. In order to improve coding performance under mobile environments, such as channel error and background noise, the proposed codec operates at three bit allocations between speech and channel coding with a constant gross bit-rate of 22.8 kbit/s. The speech coding bit-rates are 10.9, 12.1 and 15.9 kbit/s. It achieves high speech quality under any channel condition by switching the bit allocations and also for noisy speech by using the highest bit-rate. The preliminary subjective evaluation tests show the speech quality is improved by switching the bit allocation under error conditions. It is also comparable of superior to ITU-T Recommendation G.722 48 kbit/s for carrier-to-interference ratios (C/I) higher than 10 dB. The codec at 15.9 kbit/s also gives comparable speech quality to G.722 at 48 kbit/s under background noise conditions.

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.

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.

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.

Vector quantization is required the algorithm that minimizes the distortion error, and used for both storage and transmission of speech and image data. For a neural vector quantization, the self-creating neural network and self-deleting neural network and known for showing fine characters. In this paper, we improve the self-deleting neural network, and propose a generalization algorithm combining the creating and deleting neural networks. We discuss algorithms with neighborhood relations compared with the proposed one. Experimental results show the effectiveness of the proposed algorithm.

High power SAW filters using newly developed Al-Sc-Cu/Ti/Al-Sc-Cu/Ti electrodes have been successfully achieved. The thickness of this new film can be controlled during the deposition process as easily as when using conventional Al-Cu alloy film, and this film can be formed into Inter Digital Transducer (IDT) electrodes using conventional Reactive Ion Etching (RIE). We evaluated the power durability of receiver top filters using the new electrodes. Results indicate that the lifetime of the new electrode system exceeds 900,000 hours at an ambient temperature of 85/spl deg/C and input power of 3l dBm, about 1,000,000 times longer under these conditions than conventional Al-Cu alloy electrode systems. The new electrodes have clear potential for use in Advanced Mobile Phone Service (AMPS) and code division multiple access (CDMA) system SAW duplexers.

We propose a self-creating method of fuzzy modeling with learning vector quantization. A self-creating neural network is used for vector quantization. There are many fuzzy models using self-organization and vector quantization. It is well known that these models effectively construct fuzzy inference rules representing distribution of input data, and are not affected by increment of input dimensions. We use a self-creating neural network for constructing fuzzy inference rules. In order to show the validity of the proposed method, we perform some numerical examples.

This paper proposes a 16 kbit/s wideband CELP coder with a high-order backward predictor and its fast coefficient calculation method. The coefficients are calculated from autocorrelations of the residual signal. The proposed calculation scheme approximately calculates the autocorrelations of the residual signal from those of the decoded output signal. Therefore, an inverse filtering of the decoded output signal and a calculation for the autocorrelations of the residual signal are not necessary, and the complexity for the backward prediction is drastically reduced. The proposed coder also adopts a multi-pulse vector quantization to efficiently represent an excitation signal as well as a multi-mode coding to enhance the performance and the channel error robustness. An MOS test shows that the proposed coder achieves superior performance for speech to that of ITU-T G.722 at 56 kbit/s and comparable performance for audio to that of G.722 at 48 kbit/s.

The full-depth, remotely-operated survey system "KAIKO", developed by the Japan Marine Science and Technology Center, comprises a launcher suspended from the Yokosuka support ship by a primary cable, and a vehicle launched from the launcher and connected by a secondary cable. This equipment is designed for deep-sea studies at depths of approximately 11,000 meters. Real-time high speed data transmission at a maximum 840 Mbps, the fastest used for any remotely operated vehicle (ROV), was needed to transmit the five-channel video signal captured by the six underwater cameras mounted on the vehicle, together with the large volume of measurement data obtained by the latest underwater surveying equipment. Because bi-directional communication is required to support the simultaneous transmission of the launcher's on-board equipment control data and the measurement data, the overall transmission rate of the entire system is 1.2 Gbps. In the design weight and electrical power consumption were kept to a minimum. An optical power monitor, which splits the optical signal immediately before the receptor and constantly monitors the optical signal power level, is also provided to ensure problems with the optical fiber and other optical transmission components contained within the cables are detected early, thus improving the overall reliability of the system. This report describes the high-speed underwater data transmission equipment developed for the KAIKO system.

This paper proposes a novel post-processing technique to improve the coding quality of CELP under background noise. It adaptively smoothes both the spectral envelope and the energy of the estimated excitation signal to reduce their temporal fluctuations, which cause the perceptual degradation. The excitation signal is calculated using the synthesized signal and the spectral parameters given from the decoder. Thus, the proposed post-processing is performed separately from the decoder. The smoothing is applied only in non-speech periods and the smoothing strength is controlled depending on the characteristics of the synthesized signal to avoid the degradation in speech and non-stationary noise periods. Subjective test results show that the proposed post-processing improves degradation mean opinion score (DMOS) by 0.2 to 0.4 for noisy speech signals, which are coded by the GSM adaptive multi-rate (AMR) codec.

Humans can communicate with each other by gestures. This paper presents a robot system with such capability. The robot detects its user by recognizing his/her face. It can accept his/her commands given by gestures. The user may use unknown gestures to the robot. If the robot does not respond to his/her gesture, the user usually iterates the same gesture. The robot detects this repetitive pattern as an intentional gesture by which the user wants to give it some order. Then it shows a little action according to the meaning of the gesture that the robot guesses. It observes the user's reaction to its action. If he/she continues the same pattern gesture, the robot considers that its understanding is right, completing the action. It also registers the pattern as a gesture of the guessed meaning. Otherwise, it iterates the same procedure by taking another action as a candidate of the meaning. We have implemented such interactive capability on our intelligent wheelchair.

Japan Marine Science and Technology Center has been developing a long-range autonomous underwater vehicle (AUV) since 1998. This vehicle was named "AUV-EX1" and it is designed to have a capability of cruising up to 300 kilometers along a pre-programmed route. The body is a streamlined shape with a total length of 10 meters and its weight of 7.5 tons. For long range cruising, key technologies are energy source and navigation. Electric-energy is supplied from lithium ion rechargeable battery and it can be combined with a fuel cell. The navigation system is based on a high accuracy inertial navigation system. The vehicle is designed to gather scientific data by an on-board water sampler, side scan sonar and CTDO. This paper presents the overview of the AUV-EX1 and test plan in the future.

JAMSTEC started on the development project of AUV in 1998 fiscal year, and the first test machine AUV-EX1 which renamed Urashima has been developed in March 2000. Urashima has many excellent features. The cruising range is relatively long and working depth is very deep. It has a new inertia navigation system with ring laser gyros. The fuel cell system will be selected for its power device. From this June, the first test in the sea of Urashima and the fuel cell test on ground have started. This paper introduces the feature of Urashima, and shows an outline of these tests.