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.

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.

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.

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.

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