Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)最新文献

{"title":"Blind adaptive beamforming based on inverse QRD-RLS","authors":"H. Hung, Yung-Ming Wei","doi":"10.1109/UT.2004.1405502","DOIUrl":"https://doi.org/10.1109/UT.2004.1405502","url":null,"abstract":"A novel blind adaptive beamforming algorithm is proposed for underwater communications. It uses the inverse QR decomposition-recursive least squares (IQRD- RLS) approach as an adaptive solution in the architecture of our recently proposed blind adaptive solution in the architecture of our recently proposed blind adaptive beamformer. Since the adaptation gain is evaluated via Givens rotation (QR decomposition), it has higher numerical stability and lower computational complexity than the RLS-based algorithm. As compared to the least mean squares (LMS)-based algorithm, it has faster convergence rate but higher computational complexity. The inherent parallel processing capability makes the systolic array implementation feasible. For performance evaluation, simulation results were obtained for the blind adaptive beamformer algorithms based on LMS, RLS and IQRD-RLS respectively. The merits of the IQRD-RLS beamformer algorithm are verified through the simulation results.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130469952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An ocean going autonomous underwater vehicle \"URASHIMA\" equipped with a fuel cell","authors":"S. Ishibashi, T. Aoki, S. Tsukioka, H. Yoshida, T. Inada, T. Kabeno, T. Maeda, K. Hirokawa, K. Yokoyama, Toshihiro Tani, R. Sasamoto, Y. Nasuno","doi":"10.1109/UT.2004.1405548","DOIUrl":"https://doi.org/10.1109/UT.2004.1405548","url":null,"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.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"155 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115278984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acrylic plastic as structural material for underwater vehicles","authors":"J. Stachiw","doi":"10.1109/UT.2004.1405581","DOIUrl":"https://doi.org/10.1109/UT.2004.1405581","url":null,"abstract":"Underwater manned vehicles and remotely operated unmanned vehicles require for their construction materials that do not corrode in the marine environment, and do not contribute significantly to the weight of the structures. One of such materials is acrylic (polymethyl methacrylate) that, in addition to the above attributes is also transparent. It allows the occupants of the submersible or underwater observatories to observe and study hydrospace, in the same manner as it allows the visitors to the aquaria to study the denizens of the sea in safety and comfort enveloped by acrylic barriers. Historically, the primary application of acrylic was in the construction of viewports in opaque pressure hulls of submersibles, ROV's and hyperbaric chambers. However, its application does not end with viewports. Whole pressure hulls of acrylic for submersibles, underwater observatories, ROV's and hyperbaric chambers have been fabricated and successfully operated. Today acrylic submersibles operate to depths of 1000 meters (10 MPa). Depths of up to 2438 meters (24.5 MPa) can be achieved economically by acrylic submersibles with proper hull design, and there is no depth limit for designs of viewports with acrylic windows. Acrylic has been found, also, to be an ideal structural material for construction of transparent walls and tunnels in land-based aquaria and shore-based underwater walkways, hotels, and laboratories where the occupants can, in comfort, observe sea life beyond the acrylic walls of the structure. Acrylic has also successfully replaced metals as construction materials for medical hyperbaric chambers utilized for pressurization of patients with oxygen. The acrylic enclosures prevent attacks of claustrophobia in patients and allow unobstructed observation of the patients by the doctor while undergoing oxygen pressurization treatments. This paper summarizes the proven approaches to the design of acrylic viewports and acrylic pressure vessels utilizing the empirical procedures of ASME PVHO-1 Safety Standard for Pressure Vessels for Human Occupancy (hereafter referred to as the Standard). It also presents for the first time the recommended analytical procedures for design of acrylic structural components and whole acrylic structures outside the scope of the standard which currently is limited to components of enclosed pressure vessels for human occupancy under differential pressure loading","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121414195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of a flapping foil underwater vehicle","authors":"S. Licht, F. Hover, M. Triantafyllou","doi":"10.1109/UT.2004.1405590","DOIUrl":"https://doi.org/10.1109/UT.2004.1405590","url":null,"abstract":"The design, construction and testing of a biomimetic flapping foil autonomous underwater vehicle are detailed. The project is a proof of concept for the use of flapping foils as the sole source of propulsion for an underwater vehicle. We intend to use the vehicle in several physical arrangements to compare the swimming performance of different shapes and foil arrangements. The vehicle was designed for maximum flexibility and scalability in terms of the number and placement of foils through the creation of self-contained modular actuators, each requiring only DC power and a connection to the vehicle Ethernet LAN. The current vehicle implementation consists of four actuators, each driving a single foil with a span of 0.40 m and an average chord of 0.10 m. The foils are paired port-starboard, with one pair at the bow and one at the stern. Each foil has a 180 degree range of motion about the roll (chordwise) axis and unrestricted motion about the pitch (spanwise) axis. The dimensions of the vehicle without the foils are approximately 2 mtimes0.5 mtimes0.5 m. Results from disparate sets of tests have been gathered to demonstrate the suitability of flapping foils for the generation of thrust and force vectoring during cruising, of thrust at zero-speed, and the development of rapid transient forces with a single foil stroke. All of these are requirements for operation in dynamic environments which impose unpredictable transient forces on an underwater vehicle","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"466 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121767798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a shallow water ambient noise database","authors":"T.S. Pieng, K. T. Beng, P. Venugopalan, M. Chitre, J. Potter","doi":"10.1109/UT.2004.1405517","DOIUrl":"https://doi.org/10.1109/UT.2004.1405517","url":null,"abstract":"The number of underwater activities and experiments in tropical waters has been growing; people are increasingly becoming interested in the development of underwater applications that rely on acoustic communications. Ambient noise is a limiting factor in the performance of underwater acoustic detection and communication systems at shallow water. Knowledge of ambient noise characteristics at a location can be helpful for ambient noise imaging systems like ROMANIS, built at Acoustic Research Laboratory. The Singapore straits and surrounding waters contain some of the busiest shipping channels in the world. Monitoring of ambient noise is of crucial interest to acousticians and oceanographers due to the high level of shipping and snapping shrimp noise in the region. Since there was no such systematic ambient noise database existing to support oceanographers and acousticians, the Acoustic Research Laboratory (ARL) at the Tropical Marine Science Institute (TMSI) has embarked on developing a shallow water ambient noise database. This Graphical User Interface (GUI)-based database benefit and enhance the research and development of marine acoustic systems. This paper describes the collection of ambient noise data and the structured compilation of this information into a useful database. The data collected covers a frequency range of 11-8300 Hz. The data is indexed and stored in a database and presented to the user via a GUI. The GUI uses an approach similar to typical Geographical Information System (GIS) databases. The user is able to select different layers of information on a map. The user may search for ambient noise data based on various parameters such as location of data collections or classification of the environment. The GUI is also integrated with Matlab/sup /spl reg//, popular mathematical analysis software, to display the time series, power spectral density and 1/3/sup rd/ octave spectrogram of the ambient noise data. The database GUI, some example data and a summary of the collected ambient noise data are presented. The high levels of noise due to shipping and snapping shrimp are all readily apparent in the data; with typical intensity levels considerably exceeding the classic reported values. Shipping noise is reported to dominate the frequency range below 1 kHz. Snapping shrimp noise is found in all warm and shallow waters. The ambient noise data collected from near a fish farm area shows that the snapping shrimp noise is dominant above 2 kHz.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"36 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116853278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Precise positioning of a transponder placed on a sea floor. 3. Improvement of convergence of iteration calculation","authors":"H. Isshiki","doi":"10.1109/UT.2004.1405506","DOIUrl":"https://doi.org/10.1109/UT.2004.1405506","url":null,"abstract":"The precise positioning of a sea bottom transponder is very important for measuring the sea bottom crustal movement. In the previous papers, it was shown that not only the position of a bottom transponder but also the underwater acoustic velocity distribution can be determined, if the position of surface transponders and ranges between the surface and bottom transponders are known. However, the convergence of iteration calculation was a weak point of the previous theory. In the present paper, this problem is reexamined from the basic point. This problem is a singular one that does not converge to a unique solution. A method to eliminate the singularity is proposed. In the previous theory, only the Newton-Raphson method was used to solve the nonlinear equation by iteration. In the present paper, a hybrid method consisting of Monte Carlo and Newton-Raphson methods is introduced. The stability of the calculation seems to be improved considerably.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130054554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Underwater gliders: recent developments and future applications","authors":"R. Bachmayer, N. Leonard, J. Graver, E. Fiorelli, Pradeep Bhatta, D. Paley","doi":"10.1109/UT.2004.1405540","DOIUrl":"https://doi.org/10.1109/UT.2004.1405540","url":null,"abstract":"Autonomous underwater vehicles, and in particular autonomous underwater gliders, represent a rapidly maturing technology with a large cost-saving potential over current ocean sampling technologies for sustained (month at a time) real-time measurements. We give an overview of the main building blocks of an underwater glider system for propulsion, control, communication and sensing. A typical glider operation, consisting of deployment, planning, monitoring and recovery are described using the 2003 AOSN-II field experiment in Monterey Bay, California. We briefly describe the recent developments at NRC-IOT, in particular, the development of a laboratory-scale glider for dynamics and control research and the concept of a regional ocean observation system using underwater gliders.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114571838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Real-time multi-channel simulation of sonar signals by spectral shaping of white noise using an array of digital signal processors","authors":"G. Varkey","doi":"10.1109/UT.2004.1405530","DOIUrl":"https://doi.org/10.1109/UT.2004.1405530","url":null,"abstract":"The signal throughput of a multi-channel sonar simulator is n*f where n is the number of channels and f is the sampling frequency. Under the simplifying assumption that higher order terms can be ignored, the processing load requirement for signal generation per sampling period is proportional to the number of signal sources - say, p - that we wish to simulate. Thus, the total instruction cycles required for the simulator may be taken as n*f*(a+p*q), where q is the average number of cycles needed to generate a signal value corresponding to a source and a is that for the ambient noise. For realistic scenario simulation, p cannot be too small. Similarly, q increases with increased sophistication of the effects to be incorporated. The total load therefore is in the range of GigaFlops. Parallel processing technology is most suited to handle such large throughput requirement. One of the attractive design approaches for the development of a Signal Noise Simulator is to use an array of standard DSP elements operating in parallel. Such a system can generate user specified scenarios with multiple moving targets, each with multiple tonals and varying degree of modulation. A number of facilities may be provided to tune the simulator output as required by the user. The modular design of such a system allows incremental building up of simulation complexity by the addition of parallel processing nodes in the form of standardised hardware modules. This paper describes the noise generation, inverse beam forming, filtering and related algorithms needed in the development of an SNS and the synchronisation issues of the parallel implementation.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126361086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamics analysis and resolved acceleration control of an autonomous underwater vehicle equipped with a manipulator","authors":"M. Ishitsuka, S. Sagara, K. Ishii","doi":"10.1109/UT.2004.1405575","DOIUrl":"https://doi.org/10.1109/UT.2004.1405575","url":null,"abstract":"This paper is concerned with dynamics analysis and control of a Autonomous Underwater Vehicle (AUV) equipped with a manipulator. First, kinematics and dynamics of a 2-link underwater manipulator mounted on \"Twin-Burger\", and a Resolved Acceleration Control (RAC) method are described. Next, since the coordinate action between manipulator and AUV is required, the routing algorithm considering the dynamic manipulability of the robot is proposed. Computer simulation using the RAC method and the routing algorithm shows the good control performance.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124224269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ocean Exploration: building innovative partnerships in the spirit of discovery","authors":"C. Mclean, J. Manley, F. Gorell","doi":"10.1109/UT.2004.1405452","DOIUrl":"https://doi.org/10.1109/UT.2004.1405452","url":null,"abstract":"NOAA's Office of Ocean Exploration (OE) is engaged on an innovative mission to expand the knowledge of the seas. To complete this mission, OE works with a broad spectrum of partners and projects. Both the international and industrial communities offer valuable contributions to ocean exploration. This paper describes these partnerships and offers ideas for future collaborative efforts to explore the oceans.","PeriodicalId":437450,"journal":{"name":"Proceedings of the 2004 International Symposium on Underwater Technology (IEEE Cat. No.04EX869)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128493113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}