NOAA’s National Undersea Research Program

2000 ◽  
Vol 34 (4) ◽  
pp. 61-68 ◽  
Author(s):  
Andrew N. Shepard
Keyword(s):  
Research Program ◽  
Environmental Changes ◽  
Autonomous Underwater Vehicles ◽  
Underwater Vehicles ◽  
Federal Program ◽  
Ocean Science ◽  
Oceanographic Research ◽  
And Performance ◽  
Scientific Diving

The National Oceanic and Atmospheric Ad/ministration (NOAA) works to understand ocean and Great Lakes’ environments and their resources, and develop the capability to predict environmental changes. This mission requires a comprehensive oceanographic research program, including the use of undersea technologies. The in situ undersea approach to ocean science allows acquisition of otherwise unobtainable observations, samples, and experimentation. NOAA’s National Undersea Research Program (NURP) places scientists underwater, directly through the use of submersibles, underwater laboratories, and wet diving, or indirectly using remotely operated vehicles (ROVs), autonomous underwater vehicles (AUVs), and ocean observatories. Scientific diving is an integral part of NURP’s research efforts. The program seeks to safely maximize the capabilities of the nation’s scientific diving community through direct assistance from program experts, and development of new and improved technologies. NURP is also the only federal program with the legislative mandate to improve the safety and performance of divers.

Thrust Production in Highly Flexible Pectoral Fins: A Computational Dissection

2011 ◽  
Vol 45 (4) ◽  
pp. 56-64 ◽  
Author(s):  
Srinivas Ramakrishnan ◽  
Meliha Bozkurttas ◽  
Rajat Mittal ◽  
George V. Lauder
Keyword(s):  
Computational Analysis ◽  
Autonomous Underwater Vehicles ◽  
Underwater Vehicles ◽  
Bluegill Sunfish ◽  
Robust Performance ◽  
Pectoral Fin ◽  
Pectoral Fins ◽  
And Performance ◽  
Thrust Production ◽  
Computational Dissection

AbstractBluegill sunfish pectoral fins represent a remarkable success in evolutionary terms as a means of propulsion in challenging environments. Attempts to mimic their design in the context of autonomous underwater vehicles have overwhelmingly relied on the analysis of steady swimming. Experimental observations of maneuvers reveal that the kinematics of fin and wake dynamics exhibit characteristics that are distinctly different from steady swimming. We present a computational analysis that compares, qualitatively and quantitatively, the wake hydrodynamics and performance of the bluegill sunfish pectoral fin for two modes of swimming: steady swimming and a yaw turn maneuver. It is in this context that we comment on the role that flexibility plays in the success of the pectoral fin as a versatile propulsor. Specifically, we assess the performance of the fin by conducting a “virtual dissection” where only a portion of fin is retained. Approximately 90% of peak thrust for steady swimming is recovered using only the dorsal half. This figure drops to 70% for the yaw turn maneuver. Our findings suggest that designs based on fin analysis that account for various locomotion modes can lead to more robust performance than those based solely on steady swimming.

Docking Method for Hovering-Type AUVs Based on Acoustic and Optical Landmarks

2018 ◽  
Vol 30 (1) ◽  
pp. 55-64 ◽  
Author(s):  
Toshihiro Maki ◽  
◽  
Yoshiki Sato ◽  
Takumi Matsuda ◽  
Kotohiro Masuda ◽  
...  
Keyword(s):  
Power Transmission ◽  
Autonomous Underwater Vehicles ◽  
Underwater Vehicles ◽  
Human Intervention ◽  
Contact Charging ◽  
Human Control ◽  
Docking Method ◽  
Position And Orientation

Autonomous underwater vehicles (AUVs) have the advantage of not requiring tether cables or human control; however, they have limited energy, and must be recovered before their batteries drain completely. To charge AUV batteries efficiently, in-situ charging systems have attracted much attention. This study proposes a method for hovering-type AUVs to dock at a seafloor station, for long-term deployment of the system with minimum human intervention. In the proposed method, an AUV docks at a seafloor station autonomously, based on both acoustic and optical landmarks attached to the station. The AUV stochastically estimates its position and orientation with regard to the station, and controls itself to land on the exact docking spot at the station. When docking is completed, the station begins electric power transmission via non-contact charging devices. The proposed method was evaluated on the AUV Tri-TON 2, and a seafloor station testbed. The vehicle succeeded in autonomous docking at the station in both the tank and sea trials. Non-contact charging during docking was also verified during the tank experiments, using the non-contact charging devices developed by our group.

AUV Sensors for Real-Time Detection, Localization, Characterization, and Monitoring of Underwater Munitions

2009 ◽  
Vol 43 (4) ◽  
pp. 76-84 ◽  
Author(s):  
Richard Camilli ◽  
Brian S. Bingham ◽  
Michael V. Jakuba ◽  
Anthony N. Duryea ◽  
Rand LeBouvier ◽  
...  
Keyword(s):  
Real Time ◽  
Situation Awareness ◽  
Chemical Sensors ◽  
Autonomous Underwater Vehicles ◽  
Underwater Vehicles ◽  
Chemical Plume Tracing ◽  
Plume Tracing ◽  
Chemical Plume ◽  
New Research

AbstractThis technical paper describes existing capabilities and new research results for autonomous underwater vehicles (AUVs) for use in locating, characterizing, and monitoring underwater munitions. The authors introduce advances in sensor technologies and search methods pertinent to AUV-based underwater munition mitigation operations. Results are presented from a series of trials using in situ chemical sensors to detect both conventional and nonconventional underwater munitions in real time. These technologies are considered within the context of chemical plume tracing and biomimetic search algorithms. This paper concludes with a look toward future AUV sensor payloads with more extensive real-time situation awareness. Advancement of these technologies and methods will be critical for realizing the potential of AUV platforms to manage the risks posed by underwater munitions sites.

Hybrid Underwater Glider for Underwater Docking: Modeling and Performance Evaluation

2014 ◽  
Vol 48 (6) ◽  
pp. 112-124 ◽  
Author(s):  
Shilin Peng ◽  
Canjun Yang ◽  
Shuangshuang Fan ◽  
Shaoyong Zhang ◽  
Pinfu Wang ◽  
...  
Keyword(s):  
Dynamic Model ◽  
Autonomous Underwater Vehicles ◽  
Experimental Tests ◽  
Underwater Vehicles ◽  
Open Loop ◽  
Hydrodynamic Coefficients ◽  
Underwater Glider ◽  
Underwater Docking ◽  
Motion Performance ◽  
And Performance

AbstractThe development of a novel type of hybrid underwater glider that combines the advantages of buoyancy-driven gliders and propeller-driven autonomous underwater vehicles has recently received considerable interest. However, few studies have considered a hybrid glider with docking capability, which would expand the glider's applications. This study presents a hybrid glider with a rotatable thruster for realizing underwater docking. A tailored dynamic model of the hybrid glider is derived, and the motion performance is evaluated by simulations and experimental tests. A comparison between the experiments and simulations shows that results are in agreement, thus indicating the feasibility of the dynamic model and the accuracy of the hydrodynamic coefficients. In addition, the hybrid glider open-loop docking tests validate the feasibility of the mechanical docking system. Moreover, the experimental tests also validate the glider's different functions and indicate that the hybrid glider with rotatable thruster has high maneuverability even at low speeds. Thus, this type of hybrid glider can be used for underwater docking.

Multichannel Magnetometric System for Increasing the Search Capabilities of Autonomous Uninhabited Underwater Vehicles

2021 ◽  
Vol 7 (7) ◽  
pp. 51-60
Author(s):  
Nikolay A. SOKOLOV ◽  
◽  
Andrey V. RYCHKOV ◽  
Grigori N. SHCHERBAKOV ◽  
Igor A. EFREMOV ◽  
...  
Keyword(s):  
Autonomous Underwater Vehicles ◽  
Magnetic Anomalies ◽  
Underwater Vehicles ◽  
Water Area ◽  
Object Type ◽  
Preliminary Assessment ◽  
Spatially Distributed ◽  
Area Survey ◽  
Survey Results ◽  
And Performance

The advantages of using autonomous underwater vehicles in searching for ferromagnetic objects based on recording of spatially distributed magnetic anomalies are considered. The development lines of multichannel magnetometric search tools are shown. The potential capabilities of multichannel magnetometric systems for identifying search objects are revealed. Processing the survey results and drawing up a map of magnetic anomalies will make it possible to identify structures the geomagnetic properties of which differ essentially from the natural magnetic background. The use of such technique opens the possibility to achieve a significantly fuller information content and better reliability of the water area survey results and reveal visually undistinguished objects that have their own magnetic field. Based on the electromagnetic field and magnetostatics theory, a method for calculating the parameters and performance efficiency of the multichannel magnetometric system for autonomous underwater vehicles has been developed. The method is designed to evaluate the parameters of and capabilities for detecting ferromagnetic objects and to make a preliminary assessment of the search efficiency. The results obtained from computer simulation of the multichannel magnetometric system signals have confirmed the possibility of drawing up a map of magnetic anomalies to assess the occurrence depth and location of the search object in the ground. The shape of the search object magnetograms depends not only on the object type, but also on its orientation relative to the surface. By applying this dependence, it is possible to recognize search objects, determine their orientation and occurrence depth.

scholarly journals A Virtual Ocean framework for environmentally adaptive, embedded acoustic navigation on autonomous underwater vehicles

2021 ◽  
Author(s):  
◽  
EeShan Bhatt
Keyword(s):  
Travel Time ◽  
Sound Speed ◽  
Environmental Changes ◽  
Multipath Propagation ◽  
Autonomous Underwater Vehicles ◽  
Underwater Vehicles ◽  
The Arctic ◽  
Sea Ice Extent ◽  
Human In The Loop ◽  
Spatio Temporal

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.

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