Abstract: A system and a method are provided for determining the position of an underwater vehicle while the vehicle is operating underwater. A buoyant float stays on or near the surface of the water and is attached to the vehicle by thin tether that can include insulated wires. The vehicle moves under the water and pulls the float behind it. The float can receive a localization signal, such as a signal indicating its GPS position, and so can determine its position precisely. The position can be transmitted to the underwater vehicle over the wires located in the tether. The underwater vehicle can use sensors and/or calculations to determine the positional offset of the vehicle from the float buoy and generates its true position based on the known position of the float and the positional offset. The float can be constructed with attributes that will allow the float it operate with a greater tether length, and in turn allow the underwater vehicle to operate at greater depths.

Abstract: A system and a method are provided that allow load sharing between two or more DC output power supplies that are connected in parallel to scale the output power. As the temperature of the critical components in a power supply rises, the output voltage from that power supply will be lowered, so that the coolest supply will have the highest voltage and thus the highest current to the load. The systems and methods can operate without any additional wires connecting the supplies other than those supplying the power to the load.

Abstract: Methods and devices are provided for rescuing and recovering underwater vehicles. In one embodiment, a system is provided that includes a modular rescue device configured to attach to an underwater vehicle, such as with a tow line. The rescue device can include one or more emergency mechanisms that can be automatically and/or manually activated to aid in detecting the location of the underwater vehicle in the event of an emergency. One exemplary emergency mechanism includes a buoyancy mechanism, e.g., an expandable lift bag, configured to be inflated with a fluid to add buoyancy force to the system to pull the underwater vehicle toward a water surface. Another exemplary emergency mechanism includes a signaling mechanism configured to signal the underwater vehicle's location.

Abstract: Methods and devices are provided for rescuing and recovering underwater vehicles. In one embodiment, a system is provided that includes a modular rescue device configured to attach to an underwater vehicle, such as with a tow line. The rescue device can include one or more emergency mechanisms that can be automatically and/or manually activated to aid in detecting the location of the underwater vehicle in the event of an emergency. One exemplary emergency mechanism includes a buoyancy mechanism, e.g., an expandable lift bag, configured to be inflated with a fluid to add buoyancy force to the system to pull the underwater vehicle toward a water surface. Another exemplary emergency mechanism includes a signaling mechanism configured to signal the underwater vehicle's location.

Abstract: A method for determining the position of an underwater device includes placement of a plurality of station keeping devices on or below the surface of the water in known positions. A device to locate is provided for placement below the surface of the water, and the device to locate and the station keeping devices are provided with a synchronized time base and a common acoustic pulse time schedule. Each station keeping device sends an acoustic pulse at a time according to the common acoustic pulse schedule. The device to locate receives pulses sent by the station keeping devices and calculates a distance between itself and each station keeping device based upon the time that the acoustic pulse is sent and the time that the pulse is received. The device to locate then calculates its position based upon the distances between the device to locate and the station keeping devices.

Abstract: A system and a method are provided for determining the position of an underwater vehicle while the vehicle is operating underwater. A buoyant float stays on or near the surface of the water and is attached to the vehicle by thin tether that can include insulated wires. The vehicle moves under the water and pulls the float behind it. The float can receive a localization signal, such as a signal indicating its GPS position, and so can determine its position precisely. The position can be transmitted to the underwater vehicle over the wires located in the tether. The underwater vehicle can use sensors and/or calculations to determine the positional offset of the vehicle from the float buoy and generates its true position based on the known position of the float and the positional offset. The float can be constructed with attributes that will allow the float it operate with a greater tether length, and in turn allow the underwater vehicle to operate at greater depths.

Abstract: A method for determining the position of an underwater device includes placement of a plurality of station keeping devices on or below the surface of the water in known positions. A device to locate is provided for placement below the surface of the water, and the device to locate and the station keeping devices are provided with a synchronized time base and a common acoustic pulse time schedule. Each station keeping device sends an acoustic pulse at a time according to the common acoustic pulse schedule. The device to locate receives pulses sent by the station keeping devices and calculates a distance between itself and each station keeping device based upon the time that the acoustic pulse is sent and the time that the pulse is received. The device to locate then calculates its position based upon the distances between the device to locate and the station keeping devices. Systems and devices are also disclosed.

Abstract: Methods and devices are provided for rescuing and recovering underwater vehicles. In one embodiment, a system is provided that includes a modular rescue device configured to attach to an underwater vehicle, such as with a tow line. The rescue device can include one or more emergency mechanisms that can be automatically and/or manually activated to aid in detecting the location of the underwater vehicle in the event of an emergency. One exemplary emergency mechanism includes a buoyancy mechanism, e.g., an expandable lift bag, configured to be inflated with a fluid to add buoyancy force to the system to pull the underwater vehicle toward a water surface. Another exemplary emergency mechanism includes a signaling mechanism configured to signal the underwater vehicle's location.

Abstract: A method for determining the position of an underwater device includes placement of a plurality of station keeping devices on or below the surface of the water in known positions. A device to locate is provided for placement below the surface of the water, and the device to locate and the station keeping devices are provided with a synchronized time base and a common acoustic pulse time schedule. Each station keeping device sends an acoustic pulse at a time according to the common acoustic pulse schedule. The device to locate receives pulses sent by the station keeping devices and calculates a distance between itself and each station keeping device based upon the time that the acoustic pulse is sent and the time that the pulse is received. The device to locate then calculates its position based upon the distances between the device to locate and the station keeping devices. Systems and devices are also disclosed.

Abstract: A method for determining the position of an underwater device includes placement of a plurality of station keeping devices on or below the surface of the water in known positions. A device to locate is provided for placement below the surface of the water, and the device to locate and the station keeping devices are provided with a synchronized time base and a common acoustic pulse time schedule. Each station keeping device sends an acoustic pulse at a time according to the common acoustic pulse schedule. The device to locate receives pulses sent by the station keeping devices and calculates a distance between itself and each station keeping device based upon the time that the acoustic pulse is sent and the time that the pulse is received. The device to locate then calculates its position based upon the distances between the device to locate and the station keeping devices. Systems and devices are also disclosed.