{"title":"Biangunilateration using azimuth, elevation, and depth difference to localize submerged assets","authors":"M. J. Stanway","doi":"10.23919/OCEANS.2015.7404453","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404453","url":null,"abstract":"Most methods to estimate the position of a submerged asset rely on measuring the two-way travel time of an acoustic signal to and from a transponder mounted on that asset. Some alternative methods use one-way travel times and synchronized clocks, and others use multiple direction-only measurements from different locations. The method presented here estimates the location of a submerged asset using a single one-way acoustic ping, without synchronized clocks. The tracker must be able to estimate the direction of the incoming acoustic signal, and the submerged asset must be able to encode its own depth in the transmission. Simple trigonometry then gives the location of the submerged asset relative to the tracker.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131234685","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":"Preliminary results with a low-cost fiber-optic gyrocompass system","authors":"Andrew R. Spielvogel, L. Whitcomb","doi":"10.23919/OCEANS.2015.7404416","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404416","url":null,"abstract":"This paper reports results of preliminary numerical simulation studies and preliminary static experimental evaluation of a true-North gyrocompass system employing a commercially available low-cost inertial measurement unit (IMU) comprising a 3-axis fiber optic gyroscope (FOG) with microelectro-mechanical systems (MEMS) accelerometers. Northseeking gyrocompass systems typically employ a microprocessor system to sample the IMUs low-level raw sensor values for angular-rate and linear-acceleration at a high sampling rate, compensate for sensor bias and alignment, and compute a highlevel estimate for true-North heading, pitch, and roll. We report the results of a numerical simulation study to evaluate the potential accuracy of the proposed system, and a numerical sensitivity study to evaluate how this accuracy will change with variation in the sensor measurement noise of the gyroscopes and accelerometers. We report preliminary experimental results for a static benchtop configuration of this system which utilizes 3-axis angular-rate data and 3-axis linear acceleration sensor data to estimate the instrument's 3-degrees of freedom (DOF) attitude (heading, pitch, and roll) without using magnetometry of the Earth's magnetic field. These preliminary results for a static benchtop IMU configuration are promising, and directly applicable to static instrument deployments, but further development, testing, and evaluation is needed for the case of dynamic IMU configuration typically found on moving marine vehicles.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"44-45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130988737","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":"Sparse-representation-based adaptive interference suppression","authors":"Yishu Shi, F. Ge, Ying Chen, Sui-ling Ren","doi":"10.23919/OCEANS.2015.7401918","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401918","url":null,"abstract":"Passive sources localization in the presence of strong interferences is generally a difficult problem. A sparse-representation-based adaptive interference suppression (SRAIS) method is proposed in this paper for interference suppression and bearing estimation, which can reduce the power loss of the TOI signal and have more accurate direction-of-arrival (DOA) estimation, especially when the input powers of the TOI signal and the interferences are at the almost same level. Simulation and experimental results are also given.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132091025","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":"Preliminary feasibility study of cooperative navigation of underwater vehicles with range and range-rate observations","authors":"Zachary J. Harris, L. Whitcomb","doi":"10.23919/OCEANS.2015.7404421","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404421","url":null,"abstract":"This paper reports a preliminary feasibility study of a method for combined underwater communication and navigation of underwater vehicles (cooperative navigation) in which synchronous-clock modems are employed to measure both range and range rate on every acoustic data transmission. Few previously reported studies have utilized acoustic range rate in addition to acoustic range for the general navigation of underwater vehicles. This paper reports an observation model for range-rate measurements and preliminary anecdotal simulation studies for cooperative navigation of one underwater vehicle client with one surface vehicle server employing both range and range-rate observations to estimate the vehicle states with a delayed-state extended Kalman filter. In the simulation studies presented, the underwater vehicle is equipped with Doppler sonar navigation, attitude, and depth sensors, and the surface vehicle is equipped with a GPS. The preliminary studies suggest that the addition of range-rate measurements may not significantly improve the filter's estimate of the client's state over the case of range-only observations. The present study is very preliminary, however, and directions for future study are suggested.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"2014 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131270046","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}
Alan J. Turchik, E. Berkenpas, B. Henning, C. Shepard
{"title":"The Deep Ocean Dropcam: A highly deployable benthic survey tool","authors":"Alan J. Turchik, E. Berkenpas, B. Henning, C. Shepard","doi":"10.23919/OCEANS.2015.7401978","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401978","url":null,"abstract":"The deep ocean is a dark and unforgiving place. Buried under thousands of meters of water, the deepest part, the hadal zone, experiences extraordinary pressure. This deep seafloor habitat remains largely inaccessible to many current imaging tools. An inexpensive, reliable device is needed to explore these deep places and capture imagery of marine life in situ. The Deep Ocean Dropcam, developed by the National Geographic Society, is a low-cost research tool that can probe these depths and return valuable imagery to the surface. It combines a high-definition camera and onboard lights inside a glass pressure housing to capture high quality imagery of the deep seafloor environment. This device, deployed over 200 times in the past five years, has proven to be a robust platform for exploring the deep ocean.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131320985","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}
U. Nielsen, Mikkel Bjerregard, R. Galeazzi, T. Fossen
{"title":"New concepts for shipboard sea state estimation","authors":"U. Nielsen, Mikkel Bjerregard, R. Galeazzi, T. Fossen","doi":"10.23919/OCEANS.2015.7404386","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404386","url":null,"abstract":"The wave buoy analogy is a tested means for shipboard sea state estimation. Basically, the estimation principle resembles that of a traditional wave rider buoy which relies, fundamentally, on transfer functions used to relate measured wave-induced responses and the unknown wave excitation. This paper addresses however a newly developed concept of the wave buoy analogy but the approach presented herein is, on the contrary, not relying exclusively on transfer functions. Instead, the method combines a signal-based part, estimating wave frequency, and a model-based part, estimating wave amplitude and phase, where only the model-based part depends on transfer functions whereas the signal-based part relies on the measured vessel response alone. Case studies in terms of hypothetical examples show that the method is capable to reconstruct fully the wave elevation process of a sinusoidal regular wave; which include estimation of the wave's frequency, amplitude and phase. At this stage, the method is far from being a useful means in practical, real-situation applications but the method provides, indeed, a valuable step towards developing new approaches for shipboard sea state estimation.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114428331","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":"Extreme and non-tidal events in the Chesapeake Bay high frequency radar surface currents record","authors":"T. Updyke, L. Atkinson","doi":"10.23919/OCEANS.2015.7404579","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404579","url":null,"abstract":"The lower Chesapeake Bay high frequency radar (HFR) surface currents record now spans more than eight years from April 2007 to present day. In that time, the surface circulation has been observed during the passage of severe storms and other significant non-tidal events including those associated with periods of sustained high winds, high volume river discharge and complete reversals of tidal current direction. Tides are the dominant forcing mechanism for currents in the area; however, this paper focuses on the frequency and characterization of events representing the largest deviations from tidal flow. The data record is scrutinized during the passage of significant named storms including Ida (2009), Earl (2010), Irene (2011), Sandy (2012) and Arthur (2014). Storm events can disrupt data flow in observational networks for various reasons. Equipment may suffer damage and the power supply to equipment may be interrupted. Radar station outages and surface current map data quality are evaluated when storms passed through the area. For completely different reasons related to the complexity of the physical forcings, extreme events often present challenges for numerical modeling. An anticipated benefit of this study is that insights gained by describing the important non-tidal episodes may serve as a starting point for future work in analyzing the performance of numerical models and improving predictive capabilities for these events.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117055932","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":"A participative tool for sharing, annotating and archiving submarine video data","authors":"Y. Marcon, R. Kottmann, V. Ratmeyer, A. Boetius","doi":"10.23919/OCEANS.2015.7404630","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404630","url":null,"abstract":"The VIDLIB Deep-Sea Video Platform is an open access web-based tool for marine video data storage, streaming, sharing, and analysis. Using VIDLIB specialists can share, access and annotate the same videos from anywhere, thus accelerating the video annotation and analysis process. This way, scientists can share expert knowledge for video analysis (i.e. species identification) without the need to upload and download large video files. Moreover, the tool has the functionalities for participatory science, and science communication in that nonspecialists can ask questions or comment on what they see, and get answers from scientists. VIDLIB is available at http://vidlib.marum.de. In this paper we describe the structure and workflow of the VIDLIB Deep-Sea Video Platform and present an example of analysis from video data in the Southwest Indian Ridge.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116481680","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":"Moving targets detection and tracking in reverberation environments","authors":"Ying Chen, F. Ge, Yishu Shi, Sui-ling Ren","doi":"10.23919/OCEANS.2015.7401925","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401925","url":null,"abstract":"The moving target detection and tracking is always an important but challenging task with applications in radar and sonar, video surveillance, web search, bioinformatics, etc. An effective method for the moving target detection and tracking in reverberation environments is presented by utilizing spare and low-rank matrix decomposition. Due to the strong coherence between the beamspace data with the almost same background (reverberation structure), the matrix with beamspace data has potentially low-rank structure. Accordingly, the moving targets can be modeled as the sparse component, and separated from the reverberation.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116854746","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":"Distributed array of cooperating acoustic sensors using local time-frequency coherence analysis","authors":"C. Ioana, I. Candel, Angela Digulescu-Popescu","doi":"10.23919/OCEANS.2015.7401923","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401923","url":null,"abstract":"The distributed array of sensors is an interesting concept in the context of underwater environment monitoring. The signal processing distributed at sensors level has to have a low consumption (much less than the data transmission) and, in the same time, the processing efficiency needs to be satisfactory compared with a processing without any algorithmic complexity constraint. In this paper, we define a network of sensors which individually detect signals of interest based on the concept local time-frequency coherence analysis. This concept consists of estimating, in each analysis window, the local linear frequency modulation that matches the best the analyzed signal. This concept is much less sensitive to the time-varying energy of the signals, providing better detection performances than an energy-based detector. In addition, the sensors are organized in local sub-networks that will provide a joint detection stage. This operation consists in comparing the local time-frequency information obtained by the sensors of the sub-network and if they are the same, at the sub-network level, we decide that the detected signal is a useful one and its parameters has to be sent to the central processing level. This cooperating capability improves the performances as it is proved by the results on real data and quantified in terms of receiving operating characteristics.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117224746","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}