Download or read book Autonomous Underwater Vehicle AUV Path Planning and Adaptive On board Routing for Adaptive Rapid Environmental Assessment written by Ding Wang (Ph. D.) and published by . This book was released on 2007 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) As a special case, a thermocline- oriented AUV yoyo control and control parameter optimization methods for AREA are also developed. Finally, some AUV control algorithms for capturing fronts are developed. A frame-work for real-time TL forecasts is developed. This is the first time that TL forecasts have been linked with ocean forecasts in real-time. All of the above ideas and methods developed were tested in two experiments, FAF05 in the northern Tyrrhenian Sea in 2005 and MB06 in Monterey Bay, CA in 2006. The latter MB06 sea exercise was a major field experiment sponsored by the Office of Naval Research and the thesis compiles significant findings from this effort.
Download or read book Adaptive Path Planning for an Autonomous Marine Vehicle Performing Cooperative Navigation for Autonomous Underwater Vehicle written by Jonathan Hudson and published by . This book was released on 2012 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Adaptive path planning of an autonomous marine vehicle (surface or subsurface) in the role of a communication and navigation aid (CNA) for multiple autonomous underwater vehicles (AUVs) for survey missions is studied. This path planning algorithm can be run before deployment, based on the planned paths of the survey AUVs, or underway, based on information transmitted by the survey AUVs. The planner considers the relative depth of the CNA and survey AUVs (not previously done) allowing the CNA to better aid survey AUVs that maintain a set distance over the ocean floor while surveying. Results are presented from simulations and in-water trials for both pre-deployment and underway planning modes, the latter being preferred since it can adapt to the survey AUV path during the mission. The necessity of bounding the distance between the CNA and any survey AUV in order to bound survey AUV position error is also described.
Download or read book Autonomous Adaptive Oceanographic Feature Tracking on Board Autonomous Underwater Vehicles written by Stephanie M. Petillo and published by . This book was released on 2015 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: The capabilities of autonomous underwater vehicles (AUVs) and their ability to perform tasks both autonomously and adaptively are rapidly improving, and the desire to quickly and efficiently sample the ocean environment as Earth's climate changes and natural disasters occur has increased significantly in the last decade. As such, this thesis proposes to develop a method for single and multiple AUVs to collaborate autonomously underwater while autonomously adapting their motion to changes in their local environments, allowing them to sample and track various features of interest with greater efficiency and synopticity than previously possible with preplanned AUV or ship-based surveys. This concept is demonstrated to work in field testing on multiple occasions: with a single AUV autonomously and adaptively tracking the depth range of a thermocline or acousticline, and with two AUVs coordinating their motion to collect a data set in which internal waves could be detected. This research is then taken to the next level by exploring the problem of adaptively and autonomously tracking spatiotemporally dynamic underwater fronts and plumes using individual and autonomously collaborating AUVs.
Download or read book Underwater Vehicles written by Alexander Inzartsev and published by BoD – Books on Demand. This book was released on 2009-01-01 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the latest twenty to thirty years, a significant number of AUVs has been created for the solving of wide spectrum of scientific and applied tasks of ocean development and research. For the short time period the AUVs have shown the efficiency at performance of complex search and inspection works and opened a number of new important applications. Initially the information about AUVs had mainly review-advertising character but now more attention is paid to practical achievements, problems and systems technologies. AUVs are losing their prototype status and have become a fully operational, reliable and effective tool and modern multi-purpose AUVs represent the new class of underwater robotic objects with inherent tasks and practical applications, particular features of technology, systems structure and functional properties.
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 Path Planning of AUVs for Adaptive Sampling written by Namik Kemal Yilmaz and published by . This book was released on 2005 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) A real-world problem is also solved by the second method taking two different approaches. The first approach (static approach) involves a three-day-long adaptive sampling mission using the uncertainty information available on the first day. The second approach (dynamic approach) involves updating of the uncertainty information for each day using data assimilation features of the Harvard Ocean Prediction System and the Error Subspace Statistical Estimation system. The dynamic method is illustrative of how path planning for adaptive sampling fits into modern dynamic data driven oceanography. The results from the dynamic approach show that the uncertainty of the forecast decreases and becomes confined to a smaller region, indicating the strength of the method.
Download or read book Robust Online Adaptive Sensor driven Survey Planning for Single and Multiple Autonomous Underwater Vehicles written by Liam Daniel Paull and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the thesis is to propose new survey planning methods for autonomous underwater vehicles (AUVs). Historical approaches to the problem usually involve preplanning paths before the start of the survey in a structured, either zig-zag or lawn mower, pattern. This has three notable shortcomings: 1) The AUV may not be able to follow the prescribed path exactly, for example if there are unexpected disturbances, 2) Object detection in imagery obtained from the survey is dependent on many factors, some of which may not be known a priori, resulting in overly conservative plans, and 3) In the absence of pre-placed beacons, once the vehicle submerges, its location estimate will drift, again resulting in deviation from the pre-specified path. These issues are overcome here using new online and adaptive approaches to survey planning. First, an algorithm is developed that maintains a model of the area coverage over the workspace in real-time and plans paths within that workspace. This sensordriven algorithm is also able to account for uncertainty in the factors that affect object detection while underway. Second, the algorithm is augmented to explicitly account for the uncertainty in the A UV location estimate. The link between area coverage and state estimation is made. It is motivated that for coverage, estimating the full trajectory ( or smoothing) as opposed to just the present pose ( or filtering) is beneficial. In addition, the planning strategies previously developed are augmented to operate within the new probabilistic framework. The main benefit of the proposed approach is that it is robust to localization sensor noise and can guarantee coverage in a real field coverage sense not just a planning sense. Finally, the algorithms are extended to coverage with multiple AUVs. If a team of AUVs possess precisely synchronized clocks, then when they communicate underwater they can also calculate their relative ranges from the time-of-flight of the acoustic signals. A cooperative trajectory estimation algorithm is developed that is particularly well-suited to operate within the challenging underwater communications channel. Data to be transmitted in each broadcast communication scales linearly with the number of vehicles in the AUV team and does not backlog in the case of communication failures, which are common underwater. The algorithms are tested in simulation and in the field on the Iver2 AUV. These tests show the effectiveness of the proposed methods.
Download or read book An Adaptive Approach for Precise Underwater Vehicle Control in Combined Robot Diver Operations written by Naval Postgraduate Naval Postgraduate School and published by CreateSpace. This book was released on 2015-05-27 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: Joint robot-human operations potentially increase the efficiency, effectiveness and safety of the tasks they perform. The utilization of an autonomous underwater vehicle (AUV) as a robotic diver's assistant demands joint, dynamic operations involving precise physical interactions between an AUV, human divers, and the environment, which, in turn, requires a robust, accurate control system. A robot acting as a dive assistant would perform tasks such as tool carrying, worksite illumination, or other general assistance jobs that a "dive buddy" might perform. Such precise control of the AUV normally requires accurate knowledge of the vehicle's dynamics; however, this high level of accuracy is difficult to obtain without the employment of extensive system identification efforts. Additionally, the utility of the resulting model is greatly diminished if environmental conditions or vehicle configuration change frequently or unexpectedly. An ideal control system allows the AUV to switch between operational modes and objectives while accounting for uncertain environmental conditions, payload configurations, and possible failures of onboard actuators. Adaptive control has many applications in the underwater domain and can give a robotic diver's assistant the flexibility required to enable joint robot-diver operations. Therefore, two adaptive control system approaches, Model Reference Adaptive Control and L1 Adaptive Control, are investigated here for heave control of the Tethered, Hovering Autonomous Underwater System.
Download or read book On line Path Planning and Robust Adaptive Path Following for Underactuated Autonomous Underwater Vehicles written by Remon Al Azrak and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Autonome Unterwasservehikel (AUV) sind für den Einsatz in maritimen Gebieten mit harschen und lebensbedrohlichen Umgebungsbedingungen sowie langen Missionshorizonten unerlässlich. Die Planung solcher Missionen erfolgt dabei oft über einen übergeordneten Missionsplanungsalgorithmus, der auf Grundlage von Umgebungsdaten, wie z.B. Wetter-, Karten- und Sensordaten, Referenzwegpunkte generiert. Aufgrund zeitlich veränderlicher Missionsziele und dynamisch variierender Hindernisse, wie z.B. andere Seefahrzeuge, ist eine flexible Anpassung dieser Referenzwegpunkte zur Laufzeit unvermeidlich. Da in den meisten Anwendungsfällen eine möglichst genaue Durchquerung der Wegpunkte mit vertretbarem Stellaufwand gewünscht ist, fokussiert diese Dissertation auf die Bahnführung von AUV, die durch eine Kombination aus on-line Bahnplanung und nichtlinearen Folgeregelungskonzepten besteht. Wegen der Anforderungen von Folgeregelungen an die Glattheit der Referenzbahn (C2) werden im ersten Teil dieser Arbeit zunächst 3D Bahnplanungsalgorithmen auf Basis von Polynomen 5. Grades vorgestellt, welche die von der Missionsplanung vorgegebenen Wegpunkte interpolieren. Zur Verbesserung der numerischen Eigenschaften sowie der Reduzierung des Rechenaufwands wird dieser Ansatz auf B-Splines übertragen. Durch eine spezielle Pufferung/Fensterung einer bestimmten Anzahl an Wegpunkten wird die zusätzliche Anforderung an die on-line Planung adressiert. Im zweiten Teil der Arbeit werden ausgehend von einer eingehenden mathematischen Modellbildung von AUVs nichtlineare Folgeregelungskonzepte für den vollaktuierten und den unteraktuierten Fall (mehr Freiheitsgrade als Stellgrößen) entwickelt. Für ersteren wird eine Feedback-Linearisierung mit beobachterbasiertem Ansatz und aktiver Störunterdrückung präsentiert. Für den zweiten Fall wird ein robustes, adaptives Regelgesetz zur Kompensation von Modellunsicherheiten und Störungen entworfen. Wegen der Unteraktuierung des Systems, stellt dies eine anspruchsvolle Aufgabe dar, welche basierend auf der direkten Methode von Lyapunov und adaptiver Backstepping-Verfahren gelöst wird. Zur Robustifizierung des adaptiven Reglers kommen Parameter-Projektions-Techniken zum Einsatz. Abschließend werden formale Nachweise der Stabilität der präsentierten Regelungen angeführt und die Leistungsfähigkeit der entwickelten Ansätze anhand von detaillierten Simulationen belegt.
Download or read book An Adaptive Approach for Precise Underwater Vehicle Control in Combined Robot Diver Operations written by Naval Postgraduate Naval Postgraduate School and published by Createspace Independent Publishing Platform. This book was released on 2016-01-04 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: Joint robot-human operations potentially increase the efficiency, effectiveness and safety of the tasks they perform. The utilization of an autonomous underwater vehicle (AUV) as a robotic diver's assistant demands joint, dynamic operations involving precise physical interactions between an AUV, human divers, and the environment, which, in turn, requires a robust, accurate control system. A robot acting as a dive assistant would perform tasks such as tool carrying, worksite illumination, or other general assistance jobs that a "dive buddy" might perform. Such precise control of the AUV normally requires accurate knowledge of the vehicle's dynamics; however, this high level of accuracy is difficult to obtain without the employment of extensive system identification efforts. Additionally, the utility of the resulting model is greatly diminished if environmental conditions or vehicle configuration change frequently or unexpectedly. An ideal control system allows the AUV to switch between operational modes and objectives while accounting for uncertain environmental conditions, payload configurations, and possible failures of onboard actuators. Adaptive control has many applications in the underwater domain and can give a robotic diver's assistant the flexibility required to enable joint robot-diver operations. Therefore, two adaptive control system approaches, Model Reference Adaptive Control and L1 Adaptive Control, are investigated here for heave control of the Tethered, Hovering Autonomous Underwater System.
Download or read book Adaptive AUV assisted Diver Navigation for Loosely coupled Teaming in Undersea Operations written by Brendan O'Neill and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Human divers face immense challenges in the undersea domain due to constraints on life support, sensory input, and mobility. Due to these challenges, even simple tasks are difficult, and navigation between points of interest is key among them. However, humans have progressively utilized creativity, innovation, and research to explore the Earth's oceans at greater depths and with increased spatial and temporal detail. Autonomous underwater vehicles often lack the tools, dexterity, or flexibility to manage specific tasks or unforeseen circumstances. However, advances in inertial navigation, computation, and acoustic communication enable autonomous underwater vehicles to perform tasks outside human capability. Acoustic modem technology allows for flexible and reliable communication over an acoustic link. We propose algorithms for cooperative navigation between a diver and an autonomous underwater vehicle as a pathway toward complex undersea human-robot teams. This thesis identifies the communication, software, and algorithmic tools to enable loosely-coupled cooperative navigation between an autonomous underwater vehicle and a diver without a surface presence. Divers present new challenges for cooperative navigation based on their unique motion profile and variable pace from diver to diver. By leveraging the vehicle's sensor suite, acoustic modem technology, and nonlinear least-squares state estimation, we enable enhanced diver localization and navigation without a surface presence. Adaptation to environmental impacts is explored through measured ocean currents as well as updates to the diver's motion model based on state estimation analysis. These adaptations produce more efficient diver transits with fewer heading changes. In addition, maneuvering strategies for autonomous underwater vehicles are explored to assess their impact on diver localization accuracy. Experimental validation is shown through surface platforms as proxies for the autonomous underwater vehicle and diver, demonstrating the localization accuracy within a few meters for experiments under various operating conditions. These contributions provide a foundation for undersea human-robot teams to engage in complex tasks with greater efficiency through their combined strengths.
Download or read book Advances in Unmanned Marine Vehicles written by G.N. Roberts and published by IET. This book was released on 2006-01-31 with total page 461 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unmanned marine vehicles (UMVs) include autonomous underwater vehicles, remotely operated vehicles, semi-submersibles and unmanned surface craft. Considerable importance is being placed on the design and development of such vehicles, as they provide cost-effective solutions to a number of littoral, coastal and offshore problems. This book highlights the advanced technology that is evolving to meet the challenges being posed in this exciting and growing area of research.
Download or read book Real Time Adaptive Control of an Autonomous Underwater Vehicle AUV written by Michael H. Davis and published by . This book was released on 1989 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this research the problem of designing a controller for the dive maneuver of an Autonomous Underwater Vehicle (AUV) is addressed. The highly nonlinear nature of the vehicle dynamics and the requirement for the fast maneuvering call for robust control techniques. In particular Variable Structure Control (VSC) combined with Adaptive Control (AC) techniques seem to yield satisfactory performance in terms of robustness, capability to adjust to different operating conditions, and speed of response. Also linear robust techniques based on LQG and robust observers are presented to address the case when the whole state (in terms of pitch rate, pitch, and depth) is not available for measurement. Autonomous underwater vehicle; Variable structure control; AUV; Sliding mode control; Doyle-Stein observer; Adaptive control; Thesis; Sea floor mapping; Target identification; Remote reconnaissance; Underwater tracking.
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 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 97 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 A Virtual Ocean Framework for Environmentally Adaptive Embedded Acoustic Navigation on Autonomous Underwater Vehicles written by Bhatt. EeShan C. and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Autonomous underwater vehicles (AUVs) are an increasingly capable robotic platform, with embedded acoustic sensing to facilitate navigation, communication, and collaboration. The global positioning system (GPS), ubiquitous for air- and terrestrial-based drones, cannot position a submerged AUV. Current methods for acoustic underwater navigation employ a deterministic sound speed to convert recorded travel time into range. In acoustically complex propagation environments, however, accurate navigation is predicated on how the sound speed structure affects propagation. The Arctic's Beaufort Gyre provides an excellent case study for this relationship via the Beaufort Lens, a recently observed influx of warm Pacific water that forms a widespread yet variable sound speed lens throughout the gyre. At short ranges, the lens intensifies multipath propagation and creates a dramatic shadow zone, deteriorating acoustic communication and navigation performance. The Arctic also poses the additional operational challenge of an ice-covered, GPSdenied environment. This dissertation demonstrates a framework for a physics-based, model-aided, real-time conversion of recorded travel time into range--the first of its kind--which was essential to the successful AUV deployment and recovery in the Beaufort Sea, in March 2020. There are three nominal steps. First, we investigate the spatio-temporal variability of the Beaufort Lens. Second, we design a human-in-the-loop graphical decision-making framework to encode desired sound speed profile information into a lightweight, digital acoustic message for onboard navigation and communication. Lastly, we embed a stochastic, ray-based prediction of the group velocity as a function of extrapolated source and receiver locations. This framework is further validated by transmissions among GPS-aided modem buoys and improved upon to rival GPS accuracy and surpass GPS precision. The Arctic is one of the most sensitive regions to climate change, and ^as warmer surface temperatures and shrinking sea ice extent continue to deviate from historical conditions, the region will become more accessible and navigable. Underwater robotic platforms to monitor these environmental changes, along with the inevitable rise in human traffic related to trade, fishing, tourism, and military activity, are paramount to coupling national security with international climate security.
Download or read book Underwater Vehicles Design and Applications written by George M. Roman and published by . This book was released on 2021-02-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Underwater Vehicles: Design and Applications first explores the application of the adaptive Kalman filter algorithm to the estimation of high speed autonomous underwater vehicle dynamics.The authors investigate the performances of different control schemes, from non-model-based to model-based and adaptive model-based, implemented on a low-inertia underwater vehicle for three-dimensional helical trajectory tracking.Control laws for collision avoidance in three-dimensional environments are introduced, considering scenarios where a vehicle detects arbitrarily shaped and nonconvex obstacles using sensors.
