Download or read book Advances in Passive Acoustic Detection Localization and Tracking Applied to Unmanned Underwater Vehicles written by Kristen Railey Kita and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detection, classification, localization, and tracking (DCLT) of unmanned underwater vehicles (UUVs) in the presence of shipping traffic is a critical task for passive acoustic harbor security systems. In general, vessels can be tracked by their unique acoustic signature due to machinery vibration and cavitation noise. However, cavitation noise of UUVs is considerably quieter than ships and boats, making detection significantly more challenging. In this thesis, I demonstrated that it is possible to passively track a UUV from its highfrequency motor noise using a stationary array in shallow-water experiments with passing boats. First, causes of high frequency tones were determined through direct measurements of two UUVs at a range of speeds. From this analysis, common and dominant features of noise were established: strong tones at the motor’s pulse-width modulated frequency and its harmonics. From the unique acoustic signature of the motor, I derived a high-precision, remote sensing method for estimating propeller rotation rate. In shallow-water UUV field experiments, I demonstrated that detecting a UUV from motor noise, in comparison to broadband noise from the vehicle, reduces false alarms from 45% to 8.4% for 90% true detections. Beamforming on the motor noise, in comparison to broadband noise, improved the bearing accuracy by a factor of 3.2×. Because the signal is also high-frequency, the Doppler effect on motor noise is observable and I demonstrate that range rate can be measured. Furthermore, measuring motor noise was a superior method to the “detection of envelope modulation on noise” algorithm for estimating the propeller rotation rate. Extrapolating multiple measurements from the motor signature is significant because Bearing-Doppler-RPM measurements outperform traditional bearing-Doppler target motion analysis. In the unscented Kalman filter implementation, the tracking solution accuracy for bearing, bearing rate, range, and range rate improved by a factor 2.2×, 15.8×, 3.1×, and 6.2× respectively. These findings are significant for improving UUV localization and tracking, and for informing the next-generation of quiet UUV propulsion systems.

Download or read book Demonstration of Passive Acoustic Detection and Tracking of Unmanned Underwater Vehicles written by Kristen Elizabeth Railey and published by . This book was released on 2018 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: In terms of national security, the advancement of unmanned underwater vehicle (UUV) technology has transformed UUVs from tools for intelligence, surveillance, and reconnaissance and mine countermeasures to autonomous platforms that can perform complex tasks like tracking submarines, jamming, and smart mining. Today, they play a major role in asymmetric warfare, as UUVs have attributes that are desirable for less-established navies. They are covert, easy to deploy, low-cost, and low-risk to personnel. The concern of protecting against UUVs of malicious intent is that existing defense systems fall short in detecting, tracking, and preventing the vehicles from causing harm. Addressing this gap in technology, this thesis is the first to demonstrate passively detecting and tracking UUVs in realistic environments strictly from the vehicle’s self-generated noise. This work contributes the first power spectral density estimate of an underway micro-UUV, field experiments in a pond and river detecting a UUV with energy thresholding and spectral filters, and field experiments in a pond and river tracking a UUV using conventional and adaptive beamforming. The spectral filters resulted in a probability of detection of 96% and false alarms of 18% at a distance of 100 m, with boat traffic in a river environment. Tracking the vehicle with adaptive beamforming resulted in a 6.2±5.7 ∘ absolute difference in bearing. The principal achievement of this work is to quantify how well a UUV can be covertly tracked with knowledge of its spectral features. This work can be implemented into existing passive acoustic surveillance systems and be applied to larger classes of UUVs, which potentially have louder identifying acoustic signatures.

Download or read book Autonomous Underwater Vehicles written by Jing Yan and published by Springer Nature. This book was released on 2021-11-01 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Autonomous underwater vehicles (AUVs) are emerging as a promising solution to help us explore and understand the ocean. The global market for AUVs is predicted to grow from 638 million dollars in 2020 to 1,638 million dollars by 2025 – a compound annual growth rate of 20.8 percent. To make AUVs suitable for a wider range of application-specific missions, it is necessary to deploy multiple AUVs to cooperatively perform the localization, tracking and formation tasks. However, weak underwater acoustic communication and the model uncertainty of AUVs make achieving this challenging. This book presents cutting-edge results regarding localization, tracking and formation for AUVs, highlighting the latest research on commonly encountered AUV systems. It also showcases several joint localization and tracking solutions for AUVs. Lastly, it discusses future research directions and provides guidance on the design of future localization, tracking and formation schemes for AUVs. Representing a substantial contribution to nonlinear system theory, robotic control theory, and underwater acoustic communication system, this book will appeal to university researchers, scientists, engineers, and graduate students in control theory and control engineering who wish to learn about the core principles, methods, algorithms, and applications of AUVs. Moreover, the practical localization, tracking and formation schemes presented provide guidance on exploring the ocean. The book is intended for those with an understanding of nonlinear system theory, robotic control theory, and underwater acoustic communication systems.

Download or read book Passive Acoustic Localization and Tracking Using Arrays and Directional Sensors written by Ludovic Tenorio-Hallé and published by . This book was released on 2021 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: In bioacoustics, passive acoustic localization and tracking plays an important role in studying marine mammals and other organisms that produce underwater sounds. However, the implementation of such techniques faces many practical challenges, such as lack of environmental data for accurately modeling acoustic propagation, uncertainties in sensor position, time-synchronization of autonomous instruments, and logistical constraints due to large arrays. The three research chapters of this dissertation cumulatively address these hurdles. Chapter 2 develops a reformulation of the "double-difference" method for long-range tracking of acoustic sources. Originally developed for high-resolution localization of earthquakes across a network of widely distributed sensor, the double-difference approach is here adapted to exploit acoustic multipath on a vertical array, deployed in a deep-water waveguide. Results are shown to provide high-precision relative depth and range tracks of sources on the order of 50 km away, by compensating for biases caused by underdetermined array tilt and sound speed model. The method is demonstrated on both a towed acoustic source and a sperm whale (Physeter macrocephalus). Chapter 3 presents a passive time-synchronization technique for independent autonomous acoustic recorders. This approach relies on the coherent ambient noise sources maintaining the same statistical angular distribution around the instruments. Under this assumption, the temporal evolution of the cross-correlation function between sensor pairs reveals their relative time drift. This method enables continuous measurements of clock offset, including small-scale non-linear fluctuations of the drift, otherwise unobservable with standard time-synchronization techniques. Data from a field study in San Ignacio Lagoon, Mexico, is used to demonstrate this technique which is here applied to low frequency pulses, most likely originating from croaker fish (Sciaenidae family). Chapter 4 uses acoustic vector sensor data to track multiple sources simultaneously. The method is demonstrated on singing humpback whales (Megaptera novaeangliae) off western Maui. Here, the directional capabilities of vector sensors are exploited to identify and match azimuthal tracks from multiple sources between sensors, yielding localized whale tracks in terms of latitude and longitude over time. This approach shows potential for further applications such as tracking boats and analyzing the directional properties of ambient noise field.

Download or read book Underwater SLAM for Structured Environments Using an Imaging Sonar written by David Ribas and published by Springer Science & Business Media. This book was released on 2010-07-26 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Robotics is undergoing a major transformation in scope and dimension. From a largely dominant industrial focus, robotics is rapidly expanding into human en- ronments and vigorously engaged in its new challenges. Interacting with, assisting, serving, and exploring with humans, the emerging robots will increasingly touch people and their lives. Beyond its impact on physical robots, the body of knowledge robotics has p- duced is revealing a much wider range of applications reaching across diverse research areas and scienti?c disciplines, such as: biomechanics, haptics, neu- sciences, virtual simulation, animation, surgery, and sensor networks among others. In return, the challenges of the new emerging areas are proving an abundant source of stimulation and insights for the ?eld of robotics. It is indeed at the intersection of disciplines that the most striking advances happen. The SpringerTracts in AdvancedRobotics(STAR) is devoted to bringing to the research community the latest advances in the robotics ?eld on the basis of their signi?cance and quality. Through a wide and timely dissemination of critical - search developments in robotics, our objective with this series is to promote more exchanges and collaborations among the researchers in the community and c- tribute to further advancements in this rapidly growing ?eld.

Download or read book Localization and Tracking in Underwater Acoustic Networks Via High Data rate Multicarrier Communications written by Patrick Carroll and published by . This book was released on 2014 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technology and Applications of Autonomous Underwater Vehicles written by Gwyn Griffiths and published by CRC Press. This book was released on 2002-11-28 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: The oceans are a hostile environment, and gathering information on deep-sea life and the seabed is incredibly difficult. Autonomous underwater vehicles are robot submarines that are revolutionizing the way in which researchers and industry obtain data. Advances in technology have resulted in capable vehicles that have made new discoveries on how th

Download or read book Advances in Aquatic Target Localization with Passive Sonar written by and published by . This book was released on 2014 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation makes three key contributions: 1. Analysis of the aspect-dependent acoustic radiation patterns of an underway autonomous underwater vehicle (AUV) through full-field wave modeling. 2. A two-hydrophone cross-correlation technique that leverages multipath as well as bathymetric variations to estimate the range and bearing of a small boat, supported by a mathematically rigorous performance analysis. 3. A multi-target localization technique based on directly measuring multipath from multiple small surface vessels using a small hydrophone array mounted to the nose of an AUV, which operates by cross-correlating two elevation beams on a single bearing.

Download or read book Development and Testing of Navigation Algorithms for Autonomous Underwater Vehicles written by Francesco Fanelli and published by Springer. This book was released on 2019-04-16 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on pose estimation algorithms for Autonomous Underwater Vehicles (AUVs). After introducing readers to the state of the art, it describes a joint endeavor involving attitude and position estimation, and details the development of a nonlinear attitude observer that employs inertial and magnetic field data and is suitable for underwater use. In turn, it shows how the estimated attitude constitutes an essential type of input for UKF-based position estimators that combine position, depth, and velocity measurements. The book discusses the possibility of including real-time estimates of sea currents in the developed estimators, and highlights simulations that combine real-world navigation data and experimental test campaigns to evaluate the performance of the resulting solutions. In addition to proposing novel algorithms for estimating the attitudes and positions of AUVs using low-cost sensors and taking into account magnetic disturbances and ocean currents, the book provides readers with extensive information and a source of inspiration for the further development and testing of navigation algorithms for AUVs.

Download or read book The Autonomous Underwater Vehicle Emergency Localization System written by Ronald S. Lewis and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: There is an inherent risk of loss that accompanies any operations of Autonomous Underwater Vehicle (AUV) technology. This complexity and risk are increased for AUV missions that are conducted beneath ice and in harsh environmental conditions (i.e. extreme cold, compromised visibility, etc.). Risk-based methodologies have been developed to quantify the risk of loss for specific AUV platforms prior to deployments. Their goal is to identify and mitigate where possible the significant contributors (technical or otherwise) to the overall risk of a specific operation. Not surprisingly, there is an abundant amount of literature related to successful AUV missions; however, there has been very little published work related to AUV loss. Specifically, this author is not aware of any examples of a developed procedure to employ during an AUV loss event to date, much less specific algorithms developed to locate a missing AUV. This is a subset of the AUV tracking or positioning that is rarely given specific treatment. The motivating problem is based on the loss event of an AUV during polar operations. For example, (i) the vehicle might navigate outside of its predefined spatial area through some fault or error, or, (ii) its mission involves over-the-horizon operations, i.e. beyond the range of standard acoustical tracking technologies. In either circumstance, at the end of its pre-programmed mission, the AUV fails to return to the base station. Such an eventuality defines the need for reliable, long-range acoustic tracking capability that is able to coarsely localize the AUV and subsequently enable communications and/or recovery of the AUV. The thesis describes a novel approach for an acoustic positioning system for AUV localization in harsh environments with non-standard acoustic challenges that can be implemented using only basic acoustic technology, a basic single-beacon, singlehydrophone (SBSH) system. Inversive geometric techniques are applied for source localization of a one-way traveling, asynchronous acoustic signal. This differs from the usual methods of spherical, two-way direct flight measurement based on time of arrival (TOA), or hyperbolic, one-way time difference of arrival (TDOA) target tracking for transmission based on a purely Euclidean geometry. This is a novel approach to the problem of localizing an AUV. A second method of solving the non-linear system of equations that arise from the problem using the SBSH approach is derived. Both methods, the novel Apollonian inversion geometry localization (AIGL) and the non linear system localization (NLSL), are evaluated in simulation and using live field data. It will be shown that the novel algorithm performs comparable to the standard method of solving the nonlinear systems resulting from a SBSH approach. Furthermore, in certain situations it improves the localization result.

Download or read book Deployment of a Passive Acoustic Detection System for Reactive Collision Avoidance in Autonomous Underwater Vehicles written by Oscar Alberto Viquez Rojas and published by . This book was released on 2017 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of autonomous vehicles in air, land and water has grown in recent years, with increased attention given to heavily transited areas. For the case of autonomous underwater vehicles, these regions of interest include harbors and river basins where the risk of collision rapidly increases with the number of ships. This thesis presents a collision avoidance system based on passive acoustic sensing, which may be used to alert an AUV's autonomy software of the threat that an approaching vessel may represent in such shallow water environments. Experiments were conducted to collect and process data from static and vehicle-mounted hydrophone arrays, and preliminary measurements were post-processed using various signal smoothing and data-fitting techniques. Results were then compared with a mathematical model used to describe the expected sound propagation profile, to identify how the system was limited by disturbances in the test conditions, such as variable ship speed and bearing, with respect to the vehicle's frame of reference. The benefits and limitations of each data processing approach were identified, and are herein discussed through three separate case studies to highlight the benefit of parallel-model fitting. A Bluefin SandShark AUV was used for a series of deployments performed to test the vehicle's ability to change behaviors in response to approaching vessels that present a chance of collision, relying exclusively on this passive sensing system as the alarm trigger. During the final autonomous behavior-response experiments spanning six distinct deployments, a total of 21 successful alarm triggers were recorded in the vehicle logs, along with a cumulative 142 minutes of acoustic data.

Download or read book Acoustic Based Tactical Control of Underwater Vehicles written by William J. Marr and published by . This book was released on 2003-06-01 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in command and control of Autonomous Underwater Vehicles (AUVs) using acoustic communications are crucial to future Fleet objectives, particularly in Very Shallow Water Mine Countermeasures (VSW MCM). Understanding of the capability to redirect missions, provide relatively high rate downloads of mission information, and perform cooperative tracking for multi-vehicle systems is cunently limited to some bounding data based on fixed node expenments while the impact of working in the environment presented by a moving vehicle is not understood. The main objectives of this dissertation were to investigate and demonstrate the capabilities of tactical acoustic control of a dynamic, operational underwater vehicle in the Very Shallow Water (VSW) ocean environment. This necessarily required studies on the limitations of Acoustic Control and relatively High Data Rate Transfer when using commercial acoustic modems in underwater vehicles, and an investigation of their acoustic transmission characteristics. Comprehensive empirical evidence through field validation with the ARIES vehicle indicated that reduced ranges were required for successful acoustic communications in a realistic very shallow water environment. Background noise, multipath reflections, and vehicle induced Doppler shifts all limit the communication link. Occasionally, configurations may be found where vehicle body shielding against multipath destructive interference can be used to advantage. A simulation was developed to demonstrate a solution for reducing the range and conducting multi-vehicle behaviors for cooperative tracking and acoustic communications data transfer.

Download or read book Follow the Leader Tracking by Autonomous Underwater Vehicles AUVs Using Acoustic Communications and Ranging written by Daniel P. Kucik and published by . This book was released on 2003-09-01 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: With advances in computer and sensor technologies, autonomous underwater vehicles (AUVs) are now capable of reaching a level of independent action once thought impossible. Through the use of cooperative behaviors it is possible to further increase their autonomy by allowing multiple operating AUVs to simultaneously coordinate their activities to improve the efficiency and effectiveness of the overall system. This thesis research defines the algorithms and rules needed to perform 'follow the leader' cooperative behaviors during AUV rendezvous. This is a low-level first step towards more sophisticated cooperative behaviors, such as swarming or new forms of obstacle/trap avoidance. The approach taken here differs from previous research in that it does not rely on beacons or locator sensors, but instead uses ranging and intention information shared between the vehicles using acoustic communications. Several tools and algorithms are presented to support the future development of cooperative behaviors. In particular, a previously developed 3D virtual world simulator that utilizes dynamics-based vehicle models has been enhanced to support multiple simultaneously operating vehicles. Finally, a procedural algorithm is shown to correct the relative navigation errors between two vehicles through the use of vehicle-to-vehicle communications and ranging information obtained via acoustic modems. (3 tables, 69 figures, 55 refs.)

Download or read book Underwater Acoustic Localization written by Navinda Kottege and published by LAP Lambert Academic Publishing. This book was released on 2011-04 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the advancement of the field of underwater robotics, the amount of autonomy embodied in the vehicles themselves have considerably increased while making it possible to build and deploy swarms of small autonomous underwater vehicles (AUVs). Apart from the many environmental and mechanical challenges encountered in the underwater domain, the swarming paradigm demands the need for each vehicle to be aware of the positions of at least its near neighbours. The Serafina AUV project which was initiated with the goal of developing swarming technology for the small and highly agile Serafina class AUVs requires a localization system which could cope with the dynamic and fast changing vehicle configurations while being small, reliable, robust, and energy efficient and not dependent on pre-deployed acoustic beacons. The acoustical relative localisation system proposed here uses hyperbolic and spherical localization concepts and provides each vehicle with the azimuth, range and heading of its near neighbors.

Download or read book Bearings only Tracking Automation for a Single Unmanned Underwater Vehicle written by Danica Lee Middlebrook and published by . This book was released on 2007 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unmanned underwater vehicles have various missions within civilian, military and academic sectors. They have the ability to explore areas unavailable to manned assets and to perform duties that are risky to humans. In particular, UUVs have the ability to perform bearings-only tracking in shallow areas near shorelines. This thesis presents a guidance algorithm for this particular mission. This thesis first presents a Modified Polar Extended Kalman Filter for the estimation problem. Bearings-only tracking is a nonlinear problem that requires some sort of estimator to determine the target state. The guidance algorithm is developed based on the relative positions of the observer and the target. In order to develop the guidance algorithm, the effectiveness of a variety of course maneuvers are presented. The effectiveness of these maneuvers are analyzed both quantitatively and qualitatively. The results from this analysis is incorporated into the final guidance algorithm. This thesis also evaluates the developed guidance algorithm through a series of simulation experiments. The experiments explore a variety of scenarios by varying speed, geometry and acoustic environment. The results of the experiments are analyzed based on estimation errors and detection time. The final conclusions indicate that some of the geometries are more favorable than others. In addition, the degree of noise in the acoustic environment affects the range of the UUV's sensors and the UUV's ability to perform bearings-only tracking for an extended period of time. In addition, the desired speed ratio is one in which the observer is either the same speed as or slower than the target.

Download or read book Advances in Autonomous Underwater Vehicle Based Passive Bottom Loss Estimation by Processing of Marine Ambient Noise written by and published by . This book was released on 2015 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accurate modeling of acoustic propagation in the ocean waveguide is important to SONAR-performance prediction, and requires, particularly in shallow water environments, characterizing the bottom reflection loss with a precision that databank-based modeling cannot achieve. Recent advances in the technology of autonomous underwater vehicles (AUV) make it possible to envision a survey system for seabed characterization composed of a short array mounted on a small AUV. The bottom power reflection coefficient (and the related reflection loss) can be estimated passively by beamforming the naturally occurring marine ambient-noise acoustic field recorded by a vertical line array of hydrophones. However, the reduced array lengths required by small AUV deployment can hinder the process, due to the inherently poor angular resolution. In this dissertation, original data-processing techniques are presented which, by introducing into the processing chain knowledge derived from physics, can improve the performance of short arrays in this particular task. Particularly, the analysis of a model of the ambient-noise spatial coherence function leads to the development of a new proof of the result at the basis of the bottom reflection-loss estimation technique. The proof highlights some shortcomings inherent in the beamforming operation so far used in this technique. A different algorithm is then proposed, which removes the problem achieving improved performance. Furthermore, another technique is presented that uses data from higher frequencies to estimate the noise spatial coherence function at a lower frequency, for sensor spacing values beyond the physical length of the array. By "synthesizing" a longer array, the angular resolution of the bottom-loss estimate can be improved, often making use of data at frequencies above the array design frequency, otherwise not utilized for beamforming. The proposed algorithms are demonstrated both in simulation and on real data acquired during several experimental campaigns.

Download or read book Department of Defense Appropriations for written by United States. Congress. House. Committee on Appropriations and published by . This book was released on 1994 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt: