jueves, 4 de agosto de 2016

Hydrogen Fuel Cells for combat UUVs


The U.S. Navy has been evaluating alternative power generation solutions from General Atomics, General Motors, Lynntech and NexTech Materials, to power its next generation of combat UUVs.


More concretely, the Navy has been evaluating hydrogen fuel cell technologies to convert high-energy hydrogen into electricity that, when applied to a UUV, will result in a vehicle with greater range and endurance than those powered with batteries.


Also, hydrogen fuel cell propulsion technology helps address the two major environmental challenges (petroleum use and carbon dioxide emissions) as fuel cell vehicles can operate on renewable hydrogen from sources like wind and biomass stored for later use. Once converted to electricity, water vapor is the only emission. Recharging takes only minutes.


Finally, the US Navy has selected the General Motor’s (GM) hydrogen fuel cell technology to power its latest UUV under the ONR’s Innovative Naval Prototype program for Large Displacement UUVs (LDUUV), conceived for UUVs with more than 60 days endurance. Mainly, the GM option has been based in the cost of the cells, as a lower cost can be achievable through volume production supporting automotive applications.


Last but not least, GM’s fuel cells are compact and lightweight and have high reliability and performance. These attributes match the goals of the Navy to develop reliable, affordable systems. “The collaboration with the Navy leveraged what we learned in amassing more than 3 million miles of real-world experience with our Project Driveway fuel cell program,” said Charlie Freese, executive director of GM Global Fuel Cell Activities. “Our customers will benefit from additional lessons we learn about the performance of fuel cells in non-automotive applications that will be useful in GM’s drive to offer fuel cells across consumer markets.”


“Fuel cells can be game changers for autonomous underwater systems,” said Frank Herr, ONR’s department head for Ocean Battlespace Sensing. “Reliability, high energy, and cost-effectiveness — all brought to us via GM’s partnering — are particularly important as Navy looks to use UUVs as force multipliers.” The Naval Research Laboratory recently concluded an evaluation of a prototype UUV equipped with a GM fuel cell, in pools at the Naval Surface Warfare Center in Carderock, Md. The next step could be to test the LDUUV in the open sea this year, in order to field a first squadron of the robotic submarines by 2020.

martes, 19 de enero de 2016

The Navy's rising tide of UUVs


Unmanned aircrafts get all the attention nowadays, but it is beneath the waves where robots are making a splash: From detecting and clearing underwater mines to reconnaissance and mapping the ocean floors, Unmanned Underwater Vehicles (UUVs) are becoming increasingly prominent.


Like their robotic counterparts in the air, on land and on the ocean surface, underwater craft are great for dull, dirty and dangerous tasks. They can search for and clear mines while their operators remain safely at a distance, map the ocean floor for monotonous mile after mile, or conduct surveillance of ships and harbors.


A 2009 RAND Corp. study lays out a litany of possible UUV uses, including quick strikes from underwater craft quietly positioned close to their targets, anti-submarine warfare and cyber warfare by accessing underwater communications links. Naval Sea Systems Command (NAVSEA) has several UUV projects underway, according to spokesman Matt Leonard. These include: (Continue Reading)