Browse Publications
2009 Reports
Note: Unless linked to the full text, reports are only available to NATO member nations from designated distribution centres.
Sea Mine Countermeasures: Exploring Neutralisation Options: Proceedings of a workshop on innovative solutions for sea mine disposal. Djapic, V., Editor. NURC-CP-2009-002. April 2009.
NURC hosted a workshop on innovative solutions for sea mine disposal "Sea Mine Countermeasures: Exploring Neutralisation Options", 14-15 April 2009. Twenty-seven people representing ten different NATO nations from the operational (military), academic, government labs, and industry communities attended the workshop. The challenges and problems in mine neutralisation caused by sea currents, surge, and other environmental factors were covered in several presentations. Since different situations require different options, participants concluded that there is a need for a toolbox of modular autonomous systems. New candidate technologies for effective remote delivery of mine neutralisation weapons were reviewed, including non-traditional (non-explosive) approaches. The focus was on lowering costs without sacrificing key performance, especially in countering modern sea mines. Remote mine neutralization options may also be utilised in areas where conventional mine disposal systems are ineffective due to constraints of water depth or manoeuvering room. The workshop also identified partners for collaborative research and the establishment of a joint research project (JRP) on this topic. The presentations made to the workshop and the summary are compiled in these proceedings.
Self-deployable networks for battlespace shaping in denied areas: state of the art and bibliography. Berdaguer, X.; Alvarez, A. NURC-FR-2009-012. November 2009.
Sub-sea sensor/actuator networks including both static and mobile nodes are a high impact technology in naval operations. The objective of this report is to envision the technological challenges to allow active shaping operations in denied areas that occur during naval littoral operations through a state-of-the-art review in the scientific literature. We look forward to find out research and development challenges that need to be subject of further research and development. Also, special attention is paid to the self-deployment capabilities of the network and the role of unmanned undersea vehicles like AUVs and underwater gliders to act both as mobile nodes and as platforms to deploy the network static nodes.
NATO Undersea Research Centre Marine Mammal Risk Mitigation Rules and Procedures Author: Ryan, K.L. NURC-SP-2009-002. November 2009.
The NATO Undersea Research Centre (NURC) Marine Mammal Risk Mitigation Rules and Procedures provides the policy and the procedures to scientific planners, Scientists-in-Charge (SIC), researchers and the Masters of NURC vessels which address potential adverse effects on marine mammals of sea trials involving underwater sound. As a matter of policy, the Centre will take precautionary and preventive measures to circumvent harm to marine mammals from underwater sound by institution of procedures outlined in Staff Instruction 77. As new information becomes available from continued research by the Marine Mammal Risk Mitigation project, as well as other documented sources, these procedures will be reevaluated and modified as appropriate. This report supersedes the previous NURC report (NURC-SP-2008-003) which included both marine mammal and human diver risk mitigation procedures. These procedures are now separate reports.
The Barny Program: fourteen Years of NURC-NRL collaboration Perkins, H.T.; Book, J.W.; de Strobel, F.; Gualdesi, L.; Jarosz, E.; Teague, W.J. NURC-SP-2009-001. May 2009.
Shallow ocean environments, with their rapid variability, short spatial scales and often intense fishing, pose a special challenge for physical oceanographic study. Since 1995, a series of collaborative programs between NURC and the US Naval Research Laboratory (NRL) have addressed this issue. That effort has resulted in an improved capability for measurement and interpretation in water depths to 200 m, on spatial scales from hundreds of meters to hundreds of km, and on temporal scales from tidal to annual. Here we report on two aspects of this work: first, the technologies which have enabled progress in data collection and interpretation; and second, a summary of six major field programs, conducted mostly through a series of Joint Research Program between NURC and NRL, in which those technologies have been brought to bear. Taken altogether, an effective, highly mobile and affordable approach for studying ocean shallows is demonstrated.
Algorithms for the detection and classification of marine mammals Gérard, O.; Carthel, C.; Coraluppi, S. NURC-SWP-006. May 2009.
This report describes algorithms for the detection and classification of beaked whale clicks. A transient detector based on the Page test is used to detect the clicks. The clicks are classified based on their spectral information. Subsequently, based on the assumptions of slowly varying click amplitudes and inter-click-intervals, the clicks are associated using a feature aided multi-hypothesis tracking algorithm. The method is described, as well as results and various modification of the method to improve the results.
Performance studies and advanced architectures in target tracking Coraluppi, S.; Carthel, C.; Maguer, A.. NURC-FR-2009-007. May 2009.
NURC multi-hypothesis tracking technology has been developed over the past several years and applied to undersea and maritime surveillance. This report provides validation for a tracker performance model that is required in forthcoming work on sensor tasking algorithms for improved tracking performance. Additionally, we study two multi-stage tracking approaches that we term track-break-track and track-extract-track, and apply them to difficult automatic tracking scenarios. Finally, we introduce a maximum-likelihood approach to sensor data characterization, which enables more effective automatic tracker tuning.
On the feasibility of LIDAR for detecting and tracking near-surface divers and swimmers in ports Kessel, R.T. NURC-FR-2009-006. May 2009.
LIDAR (Light Detection and Ranging) has been used to detect sea-mines and to survey bathymetry in shallow water. LIDAR might therefore be used to detect and track divers near the sea surface or surface swimmers in port protection. This report investigates the extension of LIDAR to the detection and tracking of nearsurface divers or surface swimmers for port protection. The LIDAR is assumed to be air-borne or mounted on a tower. The properties of existing (commercial) air-borne LIDAR (beam width, sounding rates, cost) are extended to port protection, to investigate the feasibility of LIDAR in terms of its coverage, cost, and technology readiness. Coverage limits as a function of LIDAR altitude and sounding rate are estimated. The technical developments necessary for port protection are identified, and the unit cost of LIDAR once in production is estimated and compared with sonar.
Analysis of the AUVPET07 Trial Bryan, K. NURC-FR-2009-005. February 2009.
As NATO nations begin using AUVs equipped with sidescan sonar operationally, valid methodologies are required to evaluate their mission effectiveness. This report describes the data collected in the AUVPET07 trial and creates probability of detection versus lateral range curves for REMUS AUVs after resolving some navigational issues with the data.
Mission planning of gliders guided by remote sensing. Alvarez, A.; Reyes, E. NURC-FR-2009-004. February 2009.
The advent of autonomous platforms for ocean observation creates a demand for a correct allocation of these observational resources. The objective is to design a sampling strategy ensuring the maximum information content of the data gathered. Techniques to compute optimum sampling strategies already exist when a previous knowledge of the environment is available. Difficulties appear when observational resources must be distributed in environments where historical data is not available or too coarse to be representative of the local dynamics. Geometrical criteria are used to define sampling strategies under these circumstances. Unfortunately, these sampling procedures are in general less effective than those using a previous knowledge of the environment. This report proposes to use remote sensing to increase the optimality of sampling missions of in situ autonomous platforms in unknown areas. The procedure employs satellite data to infer a statistical model of the spatial variability in the area of interest. The statistical model is then employed to compute sampling designs minimizing the spatial average variance of the estimated field with respect to the sampled locations. Genetic Algorithm and Simulated Annealing have been implemented as minimization procedures to find the optimal trajectories of the autonomous platforms. The procedure is employed to design a sampling mission in a marine area in the Black Sea close to the Bosporus strait.
NURC’s Multistatic Sonar Project. Ehlers, F. NURC-FR-2009-003. February 2009.
Recent advances in construction technology have led to the commissioning of new classes of submarines which are very silent and highly maneuverable. Their detection by purely passive means reaches only limited performance. Active sonar systems, on the other hand, can offer sufficient performance, especially when operating in a multistatic setup, using multiple spatially distributed sources and sensors to activate and receive echoes. However, the areas of shallow waters, which are of operational interest, offer only noisy and fading channels for sound transmission. Furthermore, reverberation generates clutter contacts that add to the set of contacts originated by the target. Therefore, when applying data fusion and tracking to multistatic sonar data, it is necessary to take account of these stochastic features. This report summarizes the efforts, findings and results of NURC in the research field of multistatic active sonar. The objective of these efforts has been to determine the feasibility of interoperable surveillance with low frequency active multistatic sonar system for ASW operations and to evaluate its potential performance. Therefore, at NURC, two prototype systems have been developed to execute at-sea experimentation: a towed low frequency active system and a deployable multistatic system. Together with the development of hardware, algorithms for multistatic sonar signal processing and tracking have been implemented as NURC software products. At-sea-experimentation has been conducted in close collaboration with partners. Gathered data sets have been processed by these NURC software products. Furthermore, the data sets have been distributed to members of joint research projects or ad-hoc collaboration groups, leading to a joint analysis effort. The experimentation with the prototype showed weakness of the design concept of the prototype in that it did not allow the execution of operational experimentation. However, the acoustic data gathered in scientific experimentation clearly demonstrates the benefits of multistatics: short latency (due to effective Doppler processing), high precision (due to triangulation), less false alarms and anti-stealth. The report lists NURC’s activities related to Multistatics in the areas of technology development, scientific research, collaboration and sea trials. Analysis results are presented, describing also the application of NURC software products. Together with ‘lessons learned’ this leads to input into the concept of operational use for multistatic sonar systems.
Port Protection Close-Out Report: SPOW Projects 3J1 and 5D2. Kessel, R.T.; Strode, C. NURC-MR-2009-001. February 2009.
NURC produces a close-out report on completion of projects in its Scientific Programme of Work (SPOW). It was decided to combine the close-out reports for two related projects 1. Multi-Sensor Intruder Detection Systems for Harbour Protection (3J1), started from within NURC’s Expeditionary MCM department in 2005, 2. Requirements for Systems for Countering Intruders into Ports and Harbours (5D2), stared from within NURC’s Operation Research Department in 2006, both finishing in December 2008, in order to highlight the synergy between them. The quality of the output from both projects is reviewed here in terms of relevance for capability, external reach, innovation, and assets acquired. Lessons learned for consideration in other NURC projects are also included, as are project acknowledgements, a chronology of project highlights, and a publication list.
Requirements for a system to counter surface and underwater terrorist attacks in ports and harbours. Strode, C.; Cecchi, D.; Calabro, V. NURC-FR-2009-002. January 2009.
The following study proposes a system of organic sensors coupled with one or more USVs to provide automated protection of a high value asset against both surface and underwater terrorist attack. Fuzzy logic algorithms are developed to dynamically assign contact priorities for each USV and are shown to improve the system performance. Simulation shows that the proposed system is able to determine the intent of both surface and underwater contacts at suffcient stand-off ranges for realistic inter-arrival rates. Currently available technology to transition the proposed system to a real world solution is assessed and a number of suitable systems are suggested.
Final Report on Deloyable Multistatic Sonar Systems. Ehlers, F. NURC-FR-2009-001. January 2009.
Multistatic active sonar has become an important surveillance concept. At NURC, a focus for research on this concept was put on deployable systems with large aperture. This has led to the development of a hardware package, called DEMUS, consisting of a source and three receiver buoys. The decision was also made to work in lower frequencies, allowing large areas to be surveilled. Based on this hardware, a signal processing chain has been developed to convert received acoustic data into ‘sonar contact’ data. To fully exploit the multistatic benefits, different fusion techniques have been used to automatically generate target tracks and display them in a human machine interface. Starting from rather simple implementations of standard tracking techniques, more and more add-ons have been developed, which allow for higher precision state estimation, treatment of multiple types of sonar signals and also an adaptation to the highly variable ocean environment. The algorithms are applied to data sets gathered at sea trials conducted by NURC, and the performance is compared across different approaches.