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Abstract

My professional career has largely revolved around developing and operating Autonomous Underwater Vehicles (AUVs) for ocean science. It has proven immensely gratifying; there are very few other enterprises that offer a similar combination of interesting people, tough intellectual problems, opportunity to work in the most remote and beautiful parts of the planet, and the satisfaction of contributing to an important endeavor. This article tracks my research and development activity, starting with early technology exploration when research funding was thin, to my first field programs, to leadership of larger enterprises where AUVs became elements of integrated observation-modeling systems. Not all of the activity was in the laboratory; as the platforms matured, and applications become better defined, commercialization activity became the dominant vector of AUV capability to the larger community. Most recently, my AUV work has focused on a new generation of long-range AUVs and the biological investigations they are designed to enable. Today AUVs are accepted oceanographic tools, and science users are increasingly sophisticated. However, in the late 80s, when I started, it was not at all clear how oceanographers would employ AUVs, or what operational AUVs would look like.

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... The rst AUV arrived on the scene in 1957 [45], with development speeding up in the late 80s and 90s [2] as inertial navigation systems (INS), underwater communication and hardware technology (batteries, sensors, etc.) became better. The AUV has today become mandatory in ocean science and a variety of types are manufactured across the world; numbers from 2002 indicate 75 AUVs either under development or in operation [16]. ...
... 6 In stochastic process theory a process which has constant mean and whose covariance function is invariant to translations is called weakly stationary. A process is strictly stationary if all of its nite dimensional distributions are invariant to translations m(s) = βs = 5.42 + 0.0026 e + 0.0057 n, (2) k(s, s ) = σ 2 exp(−γ ||s − s ||), ...
Technical Report
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The backdrop for this review is rooted in ocean observation and monitoring, using machine intelligence to extend autonomous underwater vehicle (AUV) data collection capabilities. AUVs have provided scientists with a powerful tool for oceanographic research, and have changed the way ocean science is conducted, but the potential for further innovation is still great. The drive for this is twofold; sustainability and management of natural resources is regularly cited as the biggest problem of our generation. The ocean plays the central role as both a resource and early indicator for climate change, and the AUV is the tool which is best suited to provide the facts necessary for decision makers. Secondly, data collection at sea is still a challenging and an expensive enterprise; most AUV control agent systems today rely on a pre-programmed plan (Mcgann, 2007), consisting of sequential behaviors scripted with mission planning tools. This notion is not only restricted to the field of marine robotics, but information gathering platforms in general. Creative and novel solutions are therefore imperative, and constitute an excellent field for research.
... • Underwater: Landers and buoys, remotely operated vehicles (ROVs), autonomous underwater vehicles (AUVs), gliders, and pro lers. • Sea surface: Ships, and unmanned surface vehicles (USVs) • Air and space: Satellites, unmanned aerial vehicles (UAVs), and airplanes Developments in sensor-carrying platforms, sensors, control methods, autonomy, communication, and networked vehicle systems have been driven by the needs in marine sciences as described in Brighenti (1990), Singh et al. (2001), Pizarro and Singh (2003), , Ribas et al. (2008), Hagen et al. (2009), Bingham Mair et al. (2010), Sotzing and Lane (2010), , Williams et al. (2012), Sørensen et al. (2012), Seto (2013), Bellingham (2014), Dukan and Sørensen (2014), Ludvigsen et al. (2014), Fernandes et al. (2015), , Williams et al. (2015), , , and the references therein. ...
Book
Until recently, the prevailing view of marine life at high latitudes has been that organisms enter a general resting state during the dark Polar Night and that the system only awakens with the return of the sun. Recent research, however, with coordinated, multidisciplinary field campaigns based on the high Arctic Archipelago of Svalbard, have provided a radical new perspective. Instead of a system in dormancy, a new perspective of a system in full operation and with high levels of activity across all major phyla is emerging. Examples of such activities and processes include: Active marine organisms at sea surface, water column and the sea-floor. At surface we find active foraging in seabirds and fish, in the water column we find a high biodiversity and activity of zooplankton and larvae such as active light induced synchronized diurnal vertical migration, and at seafloor there is a high biodiversity in benthic animals and macroalgae. The Polar Night is a period for reproduction in many benthic and pelagic taxa, mass occurrence of ghost shrimps (Caprellides), high abundance of Ctenophores, physiological evidence of micro- and macroalgal cells that are ready to utilize the first rays of light when they appear, deep water fishes found at water surface in the Polar night, and continuous growth of bivalves throughout the winter. These findings not only begin to shape a new paradigm for marine winter ecology in the high Arctic, but also provide conclusive evidence for a top-down controlled system in which primary production levels are close to zero. In an era of environmental change that is accelerated at high latitudes, we believe that this new insight is likely to strongly impact how the scientific community views the high latitude marine ecosystem. Despite the overwhelming darkness, the main environmental variable affecting marine organisms in the Polar Night is in fact light. The light regime during the Polar Night is unique with respect to light intensity, spectral composition of light and photoperiod.
... Organic coatings are widely used in manned submersible vehicles [1,2], such as remotely operated, autonomous underwater, and human occupied ones [3][4][5][6]. The environment under deep oceans is complicated and includes hydrostatic pressure, dissolved oxygen, all types of salts, water velocity, and suspended silt. ...
... Developments in underwater technology such as platforms, sensors, control methods, autonomy, communication, and networked vehicle systems have in many cases been driven by the needs in marine sciences as described in Ludvigsen and Sørensen (2016), Nilssen et al. (2015), Sørensen and Ludvigsen (2015), Williams et al. (2012Williams et al. ( , 2015, Bellingham (2014), Seto (2013), Berge et al. (2012), Bingham et al. (2010), Moline et al. (2005), Pizarro and Singh (2003), Singh et al. (2001), and the references therein. ...
Chapter
Recent developments in underwater technology platforms including control methods, sensors, manipulators, and tools have become an enabler for more advanced and efficient underwater operations for the purpose of marine science and industrial applications such as offshore oil and gas, marine minerals, fisheries, aquaculture, and offshore renewable energy. The underwater operations may vary from mapping, monitoring, and sampling of the marine environment to inspection, maintenance, and repair (IMR) of submerged infrastructure used in, for example, subsea oil and gas. The new technology and methodology have created new opportunities for integrated operations using suitable platforms and sensors dynamically addressing the different steps in an operation from definition, planning, and replanning of mission with adaptive selection of parameters, sensor, and underwater technology platforms for knowledge generation as basis for decision-making. This section gives an overview of the different underwater technology platforms, sensors, and tools that may be used in underwater operations. Recent research efforts on control methodology going from teleoperation to increased level of autonomy will also be presented. Results and experience from selected field trials integrating different sensors and underwater platforms such as autonomous underwater vehicles (AUVs), remotely operated vehicles (ROVs), and ship-based systems carried out in the Norwegian coastal will be presented.
... This paper is an updated version of the work "Towards Integrated Autonomous Underwater Operations" by Sørensen and Ludvigsen (2015) presented at NGCUV in Girona, Spain. Developments in technology platforms, sensors and control methods including autonomy have in many cases been driven by the needs in marine sciences as described in Bellingham (2014), Seto (2013), Williams et al. (2015) including contributions from several authors, Berge, Båtnes, Johnsen, Blackwell, and Moline (2012), Bingham et al. (2010), Clark et al. (2013), Ludvigsen, Sortland, Johnsen, and Singh (2007), , Moline, Woodruff, & Evans (2007), Pizarro and Singh (2003), Singh et al. (2001), Singh, Whitcomb, Yoerger, and Pizarro (20 0 0), Williams et al. (2012) , and the references therein. The research group of Sousa (2010) at the Underwater Systems and Technologies Laboratory (LSTS), University of Porto, Portugal has done pioneering work in the development of software platforms for networked vehicle systems operating underwater, at the sea surface and in the air. ...
Article
The NTNU Centre for Autonomous Marine Operations and Systems (NTNU AMOS) is as a ten-year research program, 2013-2022, addressing research challenges related to autonomous marine operations and systems applied in e.g. maritime transportation, oil and gas exploration and exploitation, fisheries and aquaculture, oceans science, offshore renewable energy and marine mining. Fundamental knowledge is created through multidisciplinary theoretical, numerical and experimental research within the knowledge fields of hydrodynamics, structural mechanics, guidance, navigation, control and optimization. This paper gives an overview of the research at NTNU AMOS related to mapping and monitoring of the seabed and the oceans. Associated definition and requirements related to autonomy are also addressed. Results and experience from selected field trials carried out in the Norwegian coastal and Arctic waters will be presented. Integrating different sensors and sensors platforms such as Autonomous Underwater Vehicles (AUV), Remotely Operated Vehicles (ROVs), and ship-based systems will be shown.
... Developments in technology platforms, sensors and control methods including autonomy have in many cases been driven by the needs in marine sciences as described in Williams et al. (2015), Bellingham (2014), Seto (2013) including contributions from several authors, Clark et al. (2013), Williams et al. (2012), Berge et al. (2012), Bingham et al. (2010), Ludvigsen et al. (2007), Moline et al. (2005Moline et al. ( , 2007, Pizarro and Singh (2003), Singh et al. (2000Singh et al. ( , 2001, and the references therein. The research group of Sousa (2010) at the Underwater Systems and Technologies Laboratory (LSTS), University of Porto, Portugal has done pioneering work in the development of software platforms for networked vehicle systems operating underwater, at the sea surface and in the air. ...
Article
The Centre for Autonomous Marine Operations and Systems (AMOS) at NTNU (Norway) is as a ten-year research program, 2013-2022, addressing research challenges related to autonomous marine operations and systems applied in e.g. maritime transportation, oil and gas exploration and exploitation, fisheries and aquaculture, oceans science, offshore renewable energy and marine mining. Fundamental knowledge is created through multidisciplinary theoretical, numerical and experimental research within the knowledge fields of hydrodynamics, structural mechanics, guidance, navigation, control and optimization. This paper gives an overview of the research at AMOS related to underwater operations. Results and experience from selected field trials carried out in the Norwegian coastal and Arctic waters will be presented. Integrating different sensors and sensors platforms such as Autonomous Underwater Vehicles (AUV), Remotely Operated Vehicles (ROVs), and ship-based systems will be shown.
... The problem of undersampling (Munk, 2000), have to some degree been alleviated by advances in technology (Godø et al., 2014), but still huge scientific efforts are in general necessary to fill the knowledge gaps and understanding of marine ecosystems. Many recent developments in platforms and sensors have been guided by needs in the marine sciences, seeing end-users with specific applications often involved in the engineering process (Bellingham, 2014;Glenn et al., 2005;Moline et al., 2005). As new technologies helps to fill knowledge gaps in the understanding of the environment, the level of complexity regarding data management and processing also increases. ...
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New technology has led to new opportunities for a holistic environmental monitoring approach adjusted to purpose and object of interest. The proposed integrated environmental mapping and monitoring (IEMM) concept, presented in this paper, describes the different steps in such a system from mission of survey to selection of parameters, sensors, sensor platforms, data collection, data storage, analysis and to data interpretation for reliable decision making. The system is generic; it can be used by authorities, industry and academia and is useful for planning- and operational phases. In the planning process the systematic approach is also ideal to identify areas with gap of knowledge. The critical stages of the concept is discussed and exemplified by two case studies, one environmental mapping and one monitoring case. As an operational system, the IEMM concept can contribute to an optimised integrated environmental mapping and monitoring for knowledge generation as basis for decision making. Copyright © 2015 Elsevier Ltd. All rights reserved.
Chapter
Information and communication technology, autonomy, and miniaturization in terms of, for example, microelectromechanical systems are enabling technologies with significant impact on the development of sensors, sensor-carrying platforms, control systems, data gathering, storage, and analysis methods. Sensor-carrying platforms are grouped in stationary devices such as landers and moorings to dynamic platforms such as marine robotics, ships, aerial systems, and remote-sensing satellites from space. Lately, the development of low-cost small satellites with customized payload sensors and accessible mission control centers has opened for a democratization of the space for remote sensing as well. The mapping and monitoring strategy may be carried out by each type of sensor-carrying platform suitable for the mission. However, we see a quantum leap by operating heterogeneous sensor-carrying platforms for the most efficient mapping and monitoring in spatial and temporal scales. We are facing a paradigm shift in terms of resolution and coverage capabilities. There have been several research efforts to improve the technology and methodology for mapping and monitoring of the oceans. Today, we see that the mapping coverage may be 100–1000 times higher than the state-of-the-art technology 6 years ago. The entailed increase in data harvesting does also create new challenges in handling of big data sets. It is an increasing need to update the oceanographic and ecosystem numerical model capabilities, taking full benefit of the ongoing shift in technology. The Arctic can truly be characterized as a remote and harsh environment for scientific operations and even more demanding during the Polar Night due to the darkness. During winter operations, extreme coldness may also be a challenge dependent on the weather conditions. Enabling technology and proper operational procedures may be the only way to reveal and understand the processes taking place there. The spatial scale is enormous, and as several research campaigns have already taught us, the variability is huge not only during the seasons but also over the years. This clearly also tells us the importance of prolonged presence. In this chapter, we will briefly present the various sensor-carrying platforms and payload sensors. We will also describe the philosophy behind integrated operations using heterogenous platforms and why and how to bridge science and technology being successful in the development of autonomous systems for efficient and safe operations. Examples and experience from Arctic missions will also be presented.
Conference Paper
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Coastal upwelling occurs under the combined effect of wind stress and Earth's rotation. The nutrients carried up by upwelling have great impact on primary production and fisheries. For using autonomous underwater vehicles (AUVs) to investigate complex coastal upwelling ecosystems, we have developed algorithms for an AUV to autonomously distinguish between upwelling and stratified water columns based on the vertical temperature difference between shallow and deep depths, and to accurately detect an upwelling front based on the horizontal gradient of the vertical temperature difference in the water column. During a June 2011 experiment in Monterey Bay, California, the Dorado AUV flew on a transect from an upwelling shadow region (stratified water column), through an upwelling front, and into an upwelling water column. Running our algorithms, the AUV successfully classified the three distinct water types, accurately located the narrow front, and acquired targeted water samples from the three water types. Molecular analysis of the AUV-acquired water samples shows that mussels, calanoid copepods, and podoplean copepods were most abundant in the upwelling shadow region and nonexistent in the upwelling water column. Calanoid copepods were moderately abundant in the water samples collected from the upwelling front. These results are largely consistent with previous findings from zooplankton population surveys conducted with the Dorado AUV in Monterey Bay in 2009. The novel detecting and targeted sampling capabilities permit an AUV to autonomously conduct "surgical sampling" of a complex marine ecosystem. © 2012, by the American Society of Limnology and Oceanography, Inc.
Article
We address the issue of dynamic modeling and control of the Bluefin Odyssey III class vehicle "Caribou," operated by the MIT Sea Grant AUV Laboratory. Focus is on demonstrating a simple forward design procedure for the flight control system, which can be carried out quickly and routinely to maximize vehicle effectiveness. In many situations, the control loops are tuned heuristically in the field; frequent retuning is necessitated by the inevitable changes in vehicle components, layout, and geometry. Our paradigm here is that 1) a prototype controller is developed, based on an initial model, 2) this controller is then used to perform a very compact set of runs designed to identify the vehicle dynamic response, and 3) a revised, precision controller based on this improved model is implemented for the ultimate mission. We first developed a hydrodynamic model of the vehicle from theory and benchtop laboratory tests; no data from prior field tests with this vehicle was used. Body added mass approximations were included as well as lift and hydrostatic forces and moments. Inertial properties were approximated by assuming the vehicle density was that of water. Caribou's tailcone assembly consists of a double-gimbaled thrust-vectoring duct, with significant positioning dynamics and a non-traditional hydrodynamics. We carefully tested this tailcone's response behavior through laboratory tests, and created a low-order model. Using the tailcone model and the vehicle's initial hydrodynamic model, we developed a conservative controller design from basic principles. The control system consisted of a heading controller, pitch controller, and depth controller; the pitch control loop was nested inside the depth control loop. This control system was successfully tested in the field: the vehicle was controllable within several degrees of heading and approximately one-half meter of depth, on the first-pass design.
Article
Coastal marine ecosystems are profoundly influenced by processes that originate from their boundaries. These include fluid boundaries — with the atmosphere, oceanic boundary currents and terrestrial aquatic systems, as well as solid boundaries — with the seafloor and coast. Phytoplankton populations transfer complexly interacting boundary influences into the biosphere. In this contribution, we apply data from an ocean observing and modeling system to examine boundary influences driving phytoplankton ecology in Monterey Bay, CA, USA. The study was focused on species that may cause harmful algal blooms (HABs). During September – October 2010, autonomous molecular analytical devices were moored at two locations characterized by different degrees of stratification and exposure to upwelling dynamics. The time-series revealed multiple transitions in local HAB phytoplankton communities, involving diatoms (Pseudo-nitzschia spp.), dinoflagellates (Alexandrium catenella), and raphidophytes (Heterosigma akashiwo). Observational and model results showed that the biological transitions were closely related to environmental changes that resulted from a variety of boundary processes — responses of oceanic circulation to wind forcing, influxes of different water types that originated outside of the bay, and emergence of strongly stratified nearshore waters into the greater bay. Boundary processes were further implicated at patch scales. High-resolution mapping and sampling of a phytoplankton-enriched patch were conducted in a Lagrangian framework using autonomous underwater vehicles. These highly resolved measurements showed that small-scale spatial patterns in the toxicity of Pseudo-nitzschia populations were related to coupling of resuspended sediments from the bottom boundary layer to the surface mixed layer.
Article
A new architecture for controlling mobile robots is described. Layers of control system are built to let the robot operate at increasing levels of competence. Layers are made up of asynchronous modules that communicate over low-bandwidth channels. Each module is an instance of a fairly simple computational machine. Higher-level layers can subsume the roles of lower levels by suppressing their outputs. However, lower levels continue to function as higher levels are added. The result is a robust and flexible robot control system. The system has been used to control a mobile robot wandering around unconstrained laboratory areas and computer machine rooms. Eventually it is intended to control a robot that wanders the office areas of our laboratory, building maps of its surroundings using an onboard arm to perform simple tasks.
Conference Paper
An autonomous underwater vehicle (AUV) designed for operation at high latitudes and under ice, completed its first Arctic field tests from the USCGC Healy in October 2001. The ALTEX (Atlantic Layer Tracking EXperiment) AUV's initial application was focused on tracking the warm Atlantic Layer inflow - the primary source of seawater to the Arctic Ocean. The primary payloads were twin pumped CTD systems. Oxygen and nitrate sensors provide the ability to use NO (dissolved oxygen corrected by nitrate to account for biological respiration) as a nearly conservative tracer. An ice profiling sonar allowed the AUV to estimate the ice thickness in real-time and was designed to generate high quality post-processed ice draft data comparable to that collected through the SCICEX program. Sections of water properties were obtained in the marginal ice zone and ice thickness measurements made in the ice pack. Marginal ice observations showed mixing of the warm Atlantic layer to the surface, causing melting of ice even as winter approached.
Article
Oceanographic science is frequently hindered by a lack of spatial and temporal resolution for most parameters oceanographic science desires to measure. This paper discusses our effort to advance the current state of bathymetric mapping as part of the Monterey Bay Aquarium Research Institute (MBARI) charter. MBARI scientists and engineers, in consultation with the external community, have produced a new multibeam mapping autonomous underwater vehicle (AUV) system. The system is intended to reduce some of the impediments encountered by science trying to resolve specific portions of the oceans bottom. Starting with the established and in-house developed Dorado AUV technology, MBARI engineering refined the AUV into a full ocean depth capable and now operational multibeam mapping system (MBAUV). The MBAUV system conducts regular multibeam bathymetry, subbottom, and sidescan surveys for oceanographic science. MBAUV is a torpedo-shaped, 6000 m rated vehicle operating the aforementioned sonars simultaneously. The endurance of the MBAUV is approximately 8 h at 3 kn and is designed to support 16 h operations at 3 kn by adding an additional battery section. This paper describes the basics of the MBAUV and our design trades and modifications to the Dorado AUV in support of multibeam mapping missions. The paper also reviews a sampling of the results from a series of missions that demonstrate the performance of various subsystems and the science quality data available from the MBAUV. © 2007 Wiley Periodicals, Inc.
Conference Paper
The metadata oriented query assistant (MOQuA) is a web application for exploring complex collections of data via a highly interactive and intuitive interface. MOQuA development has been motivated by the evolution of climate and ecosystem studies towards highly interdisciplinary research programs that depend on data drawn from a variety of sources. Present generations of earth science data systems are not structured to support exploration through a data space that is simultaneously rich in measured parameters, yet sparse in geographic and temporal coverage. We have implemented MOQuA for the Autonomous Ocean Sampling Network 2003 field program data set, which includes observations from a diverse collection of platforms such as drifters, autonomous underwater vehicles and ships, fixed measurement assets (such as moorings and radar), and remote measurements from satellites and aircraft. It also includes output from three oceanographic models. Measured and derived data are stored in several formats, residing within numerous data management systems.
Conference Paper
The original Odyssey vehicle systems established a style of platform that has proven to be extremely versatile and useful for a variety of scientific missions. The Monterey Bay Aquarium Research Institute (MBARI) has carried forward the Odyssey design, now called Dorado. Dorado is a mid-sized vehicle in comparison to other AUV systems. Dorado vehicles are 0.5334 m (21") diameter, and are designed for deep water (4500 m) operation. The Dorado design improves upon the original Odyssey versatility by dividing the vehicle up into modular sections. Specific sections can then be built to carry out each type of mission. A Dorado vehicle can then consist of a nose section, one or several mission-specific midbodies, and a tail section. The main vehicle systems for propulsion, control, data handling, navigation, acoustic sub-systems, and most other standard functions are housed in the tail section. This paper introduces the history of the Dorado systems, and what has been accomplished to date. This paper further describes the various architectural concepts and operational results. Future planning is also discussed.
Conference Paper
The authors' goal is to greatly increase access to the Arctic Ocean by creating and demonstrating a safe and economical platform capable of basin-scale surveys. Specifically, they are developing an autonomous underwater vehicle (AUV) for Arctic research with unprecedented endurance, and the capability to relay data through the Ice to satellites. They provide a means of monitoring changes taking place in the Arctic Ocean and investigate its impact on global climate changes. The vehicle will also be capable of seafloor surveys throughout the Arctic basin. Such a capability is of national and global interest and importance
Conference Paper
The utility acoustic modem (UAM) is a high performance and compact digital signal processing system for acoustic communications, designed at Woods Hole Oceanographic Institution. The UAM is fully integrated, containing 4 hydrophone input channels, a switching power amplifier, and non-volatile memory. The device consumes 3 W when receiving and up to 30 W when transmitting with a source level of about 185 dB re microPascal. At the heart of the UAM is a 30MFLOP (million floating point operations per second) DSP chip capable of implementing a wide range of acoustic communication signalling and receiving algorithms in real-time. To date, two communications links, have been implemented on the UAM and evaluated. The first is a low-rate incoherent system using frequency-hopped FSK signalling and strong error-correction coding to provide robust communications in channels with rapidly-varying multipath. The second link is a high-rate coherent method using QPSK signalling and a Doppler-tolerant multi-channel adaptive equalizer. The two communications methods have been tested individually, and against each other, in a variety of shallow water channels. The paper reviews the design and capabilities of the UAM and describes in detail the FSK and QPSK implementations. Performance results for both schemes from at-sea experiments are then presented. The ultimate aim of the UAM development is to produce a robust communications link able to adapt modulation type and rate to the channel conditions. Some preliminary steps towards this are discussed in the light of the at-sea results
Conference Paper
Missions in which an autonomous undersea vehicle docks with an underwater node for the purpose of battery recharging and/or data transfer greatly increase the scope of potential applications possible with UUVs. Robust and accurate vehicle guidance to a small, simple and reliable docking structure is a critical capability which must be developed in order to achieve this end. This paper describes a simple but highly effective underwater vehicle guidance scheme which is based upon an optical quadrant tracker which locks onto a visible light source located at the dock in the same manner as a Sidewinder air-to-air missile tracks its target in air. An optical terminal guidance system based upon this concept was developed by NRaD. Optical guidance and docking was demonstrated using two autonomous underwater vehicles: a SeaGrant Odyssey IIB and the NRaD Flying Plug. The optical docking system was demonstrated to be accurate and robust for vehicle terminal guidance during field operations and provided targeting accuracy on the order of 1 centimeter under real-world conditions, even in turbid bay water. Such a system is projected to provide reliable terminal vehicle guidance to an underwater dock from a maximum acquisition range of approximately 100 meters in typical continental shelf ocean water
Conference Paper
When the H. A. Perry Foundation announced a competition for human-powered submarines, a group of students at MIT formed to meet the challenge. The authors describe the submarine that evolved, covering the design of the more important subsystems in detail as well as some of the thought processes and analyses involved. A safe, fast, and maneuverable human-powered submarine was the result. Attention is given to the hull design, the propulsion system, control, and human factors and safety. The authors also report on the performance of the MIT submarine on occasions other than the Florida competition.
Conference Paper
Odyssey class autonomous underwater vehicles (AUVs) are designed to be small, high performance survey platforms. The logistical complexities of operating off of oceanographic vessels or in hostile environments, such as the Arctic, make a small vehicle with minimal support requirements extremely attractive. Although built for great depths and endurances of up to two days, Odyssey class vehicles are small by the standards of existing AUVs. This paper describes Odyssey II, the second generation of Odyssey class AUV, and presents the results of under-ice field trials in New Hampshire and the Arctic
Conference Paper
In the Spring of 1994, the dynamical and mechanical behavior of the Artic ice cover was studied from an ice camp deployed in the Beaufort Sea, 2-300 nm north of Prudoe Bay. The periodic measurement of the under-ice topography is a key component of the experiment, and the authors make use of autonomous underwater vehicle (AUV) technology to provide a cost effective alternative to the use of nuclear submarines. As a proof of concept, the AUV Odyssey was used to obtain ice-topographic data from areas located up to 10 km from the base camp. Accurate and reliable navigation is crucial to successful completion of the mission and recovery of the vehicle. The planned mission is described together with the associated requirements for vehicle technology, with particular emphasis on the development of a robust, very long baseline acoustic navigation system
Conference Paper
The status of research on adapting layered control to fully autonomous underwater vehicles (AUVs) is described. Handling vehicle dynamics, communication between layers, sensor processing, mission configuration, resolving conflict between layers, and avoiding states in which the vehicle becomes trapped are studied. The complex nonlinear dynamics and large sensor processing requirements inherent in AUV applications have led to the modification of the traditional layered control approach. Of particular importance is the need to move closed-loop control and sensor processing outside the layered control architecture to reduce the memory and throughput requirements imposed on the main computer. The major research issues involved with making layered control less complex, reconfigurable, and suitable for underwater operations are considered
Article
Seagliders are small, reusable autonomous underwater vehicles designed to glide from the ocean surface to a programmed depth and back while measuring temperature, salinity, depth-averaged current, and other quantities along a sawtooth trajectory through the water. Their low hydrodynamic drag and wide pitch control range allow glide slopes in the range 0.2 to 3. They are designed for missions in a range of several thousand kilometers and durations of many months. Seagliders are commanded remotely and report their measurements in near real time via wireless telemetry. The development and operation of Seagliders and the results of field trials in Puget Sound are reported
Article
A small (50-kg, 2-m long) underwater vehicle with operating speeds of 20-30 cm/s and ranges up to 6000 km has been developed and field tested. The vehicle is essentially an autonomous profiling float that uses a buoyancy engine to cycle vertically and wings to glide horizontally while moving up and down. Operational control and data relay is provided by GPS navigation and two-way communication through ORBCOMM low-Earth-orbit satellites. Missions are envisioned with profile measurements repeated at a station or spaced along a transect. The initial instrument complement of temperature, conductivity, and pressure sensors was used to observe internal waves and tides in the Monterey underwater canyon
Article
SLOCUM is a small gliding AUV of 40 000-km operational range which harvests its propulsive energy from the heat flow between the vehicle engine and the thermal gradient of the temperate and tropical ocean. The design of both the glider and the thermal engine are discussed including the design genesis and approach, field trial results, concept strength, and limitations and potential use
Article
Central to the successful operation of an autonomous undersea vehicle (AUV) is the capability to return to a dock, such that consistent recovery of the AUV is practical. Vehicle orientation becomes increasingly important in the final stages of the docking, as large changes in orientation near the dock are impractical and often not possible. A number of homing technologies have been proposed and tested, with acoustic homing the most prevalent. If AUV orientation is required as well as bearing and distance to the dock, an acoustic homing system will require high update rates, and extensive signal conditioning. An Electromagnetic Homing (EM) system is one alternative that can provide accurate measurement of the AUV position and orientation to the dock during homing. This system offers inherent advantages in defining the AUV orientation, when compared to high frequency acoustic systems. The design and testing of an EM homing system are given, with particular attention to one can be adapted to a wide class of AUVs. A number of homing, docking, and latching trials were successfully performed with the design. Homing data include dead reckoning computation and acoustic tracking of the homing track, and video documentation of homing into the dock
State configured layered control. In: Mobile Robots for Subsea Environments, 1st International Advanced Robotics Programme
  • J G Bellingham
  • T R Consi
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A small, long-range vehicle for deep ocean exploration
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Undersea Vehicles Directory-1990 Development of underwater acoustic modems and networks
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General dynamics knifefish UUV team eyes production after finishing critical design review. Military and Aerospace Electronics
  • J Keller
Keller, J., 2013. General dynamics knifefish UUV team eyes production after finishing critical design review. Military and Aerospace Electronics 24 (5), 33–33.
The autonomous benthic explorer (ABE): an AUV optimized for deep seafloor studies
  • D R Yoerger
  • A M Bradley
  • B B Walden
Yoerger, D.R., Bradley, A.M., Walden, B.B., 1991. The autonomous benthic explorer (ABE): an AUV optimized for deep seafloor studies. In: Proceedings of the Seventh International Symposium on Unmanned Untethered Submersible Technology, UUST91, pp. 60–70.