Underwater vehicles

BE-2013 Virtual environment interface by sensory integration for inspection manioulation control in multifunctional underwater vehicles. Ptol. David Broome Tschnical Softvvare Conauttanta... 

Craven, P.J. (1999) Intelligent Control Strategies for an Autonomous Underwater Vehicle, PhD Thesis, Department of Mechanical and Marine Engineering, University of Plymouth, UK. Craven, P.J., Sutton, R. and Burns, R.S. (1997) Intelligent Course Changing Control of an Autonomous Underwater Vehicle. In Twelfth International Conference on Systems Engineering, Coventry, UK, September, 1, pp. 159-164. 

Pearson, A.R., Sutton, R., Burns, R.S. and Robinson, P. (2000) A Kalman Filter Approach to Fault Tolerance Control in Autonomous Underwater Vehicles. In Proc. 14th International Conference on Systems Engineering, Coventry, 12-14 September, 2, pp. 458 63. 

Propellers are the predominant propulsive devices driving ships, although water jets are now used in some high-speed ships. An experimental installation in a small ship of a magnetohydrodynamic propulsor has been tested, but it achieved rather low propulsive efficiency. Fish-like propulsion also has been examined for possible application to ships and underwater vehicles. 

Figure ll ICx Technologies SeaDog underwater explosives detection sensor mounted on an autonomous underwater vehicle. Figure courtesy of ICxTechnologies. 

The second box contains a peristaltic pump and a servoactuator. Both the pump and servo are controlled electrically from the sensing head and are powered from the same power supply. The separation of the sensing head from the pump and servo provide electrical and mechanical isolation and address space constraints associated with mounting the system on the autonomous underwater vehicle. The peristaltic pump enables operation at a variable flow rate and has bidirectional flow capability. The servo actuates a movable sample inlet tube that can be raised or lowered by remote control to enable precise positioning of the inlet relative to the source or in the source plume. 

To our knowledge, this is the first demonstration of a sensor capable of realtime detection of a TNT plume in the marine environment at standoff distances (up to 100 m from the source) while deployed on an autonomous underwater vehicle. The sensor has shown virtually no sensitivity to chemical interferent during testing in the marine environment. While the sensitivity of the detector is excellent, its sensitivity is not adequate at its present state of development to... 

In 2001, the Fido system was modified to operate underwater and became known as the SeaDog. The U.S. Navy Office of Naval Research (ONR), under its Chemical Sensing in the Marine Environment (CSME) Program, funded the integration of the SeaDog with an autonomous underwater vehicle (AUV). The integrated system was able to map a plume of trinitrotoluene (TNT) in open water in real time. This was the first demonstration of the mapping of an explosive plume underwater in real time [9, 10],... 

Autonomous underwater vehicle Improvised Munitions Black Book Vol. 1 l/,3-Dihydro-l/-(2-carboxyethyl)-3,3-dimethyl-6-nitrospiro [2H-1 -benzopyran-2,2/-(2H)-indoline]... 

Unmanned underwater vehicle Underwater unexploded ordnance Ultraviolet Unexploded bomb(s)... 

Torpedo. A marine weapon consisting of an underwater vehicle, a warhead, and a control mechanism, which can be a homing unit, an impact or proximity device or a time fuse. Initially developed as a surface-to-surface weapon, the torpedo has evolved into a diversified class of weapons capable of submerged launching or targeting — or both... 

Electrochemical measurements can be readily adapted for on-line monitoring. An electrochemical detector uses the electrochemical properties of target analytes for their determination in a flowing stream. An electrochemical flow system, based on an SWV operation at a carbon-fiber-based detector, for use in the on-line continuous monitoring of trace TNT in marine environments was developed [16]. Such flow detector offers selective measurements of sub-part-per-million concentrations of TNT in untreated natural water samples with a detection limit of 25ppb. It responds rapidly to sudden changes in the TNT concentration with no apparent carryover. About 600 runs can be made every hour with high reproducibility and stability (e.g., relative standard deviation (RSD) = 2.3%, n = 40). The system lends itself to full automation and to possible deployment onto various stationary mobile platforms (e.g., buoys and underwater vehicles). 

In situ electrochemical monitoring of TNT using underwater vehicle platforms... 

Fig. 7. Electrochemical explosive sensor mounted on the autonomous underwater vehicle (AUV). The three-electrode assembly (on the cone nose of the vehicle) is shown on the right side.

A.B. Laconti. The MIT/Marine Industry Collegium, Power Systems for Small Underwater Vehicles Cambridge, MA, 1988. 

Instruments in the underwater vehicle include conductivity, temperature, dissolved oxygen, depth, and irradiance sensors (Table I). In addition to these sensors, two pendula inside the electronics package provide continuous readings as to bank and climb altitudes while towing. 

Figure 2. Towed pumping system underwater vehicle.

Electrical System. The conductors in the hose-cable carry power and control signals down to the underwater vehicle and return information. The drive-pump motor is powered by three-phase, 220 V carried down three paired conductors. The solenoid valve, which controls the clean pump, is energized by 24 V direct current (DC), which is controlled on deck. The submersible pump that circulates water through in situ sensors uses 110 V alternating current (AC) power from the hose-cable. 

A watertight data management unit [underwater computer (UWC)] in the underwater vehicle takes DC power in the range from 12 to 32 V from the ship and converts this to 5 V DC with a DC-DC converter. This 5-V supply powers the UWC internal circuitry and two 15-V DC-DC converters. One converter is used for the requirements of the UWC the other is used to supply + 30 V DC and + 15 V DC to the external sensors. 

The existing configuration is not capable of routine undulation during sampling. The fairing does not always spool smoothly onto the drum as the underwater vehicle is raised and requires special attention during this maneuver. Such mechanical problems might be readily eliminated. 

M. Herman and J.S. Albus, Overview of the Multiple Autonomous Underwater Vehicles Project, IEEE International Conference on Robotics and Automation, Philadelphia, PA, 1988... 

Hasvold, O. Lian, T. Haakaas, E. Storkersen, N. Perelman, O. Cordier, S. CLIPPER a long-range, autonomous underwater vehicle using magnesium fuel and oxygen from the sea. J. Power Sources. 2004, 136 (2), 232-239. 

Because they are very quiet, and because they are inherently more efficient than diesel or other i.c. power plants, fuel cells have long been regarded by the navies of the United States, Germany, Canada, Australia, and Sweden as an attractive means of propelling small submersibles (such as unmanned underwater vehicles used for marine research, pipeline repair, salvage, and exploration), and even full-size submarines. 

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