(Credit:
ONR)
The U.S. Navy may have developed a solution to hull-dwelling barnacles and slime--a "foul" problem that has plagued sailors and their ships since Noah launched the ark.
The Office of Naval Research (ONR) has developed what looks like a combination pressure washer/minisub called the Hull Bio-inspired Underwater Grooming, or Hull BUG. It's designed to prevent or suppress the growth and build-up of nuisance marine growths such as barnacles--also known as biofouling (PDF).
This could be a major breakthrough. High-performance warships and submarines rely on a clean hull for speedy acceleration and hydroacoustic stealth--things that crustaceans easily impede.
Enter the Hull BUG. It's an autonomous, tether-free vehicle similar to an advanced pool cleaner. It uses four wheels and a negative pressure Vortex Regenerative Fluid Movement assembly to attach itself to the hull, where it deploys a variety of "grooming" tools, including rotary brushes and specialized water jets to groom and maintain ship hull surfaces.
It carries a suite of onboard sensors to provide obstacle avoidance, path planning, and navigation capabilities that include detection of fouled and groomed surfaces, according to ONR. Add weapons, and you also have a "force protection" vehicle.
Biofouling can reduce a vessel speeds by 10 percent and add 40 percent in increased fuel consumption in order to compensate for the added drag. In fact, biofouling on ships translates into roughly $500 million in extra fuel and maintenance costs annually, according to the Naval Surface Warfare Center's Carderock Division.
(Credit:
Aurora Flight Sciences Corp. )
The Excalibur, a new turbine-electric hybrid propelled VTOL (vertical takeoff and landing) unmanned attack drone, has successfully completed another test flight after taking on two new onboard computers last week.
Developed by Aurora Flight Sciences Corp. for the U.S. Army Aviation Applied Technology Directorate and the Office of Naval Research, the Excalibur is another radical robo-craft concept vying to fill the military's burgeoning demand for specialized UAVs.
The demonstrator model, weighing in at 700 pounds, can hit 520 mph, making it one of the fastest drones around, according to the Aurora. The nearly autonomous flight control system allows operators to concentrate on finding and engaging targets instead of piloting the aircraft, according to the Manassas, Va.-based company. The Excalibur's jet-borne vertical takeoff and landing and three electric lift fans providing attitude control and hover thrust, make it "runway independent." After takeoff, it flies like a regular turbojet.
(Credit:
Parvus)
There's no mistaking the mini-jet's intent. The full scale model is designed to carry a 400-pound weapon load; that would be four Hellfire Missiles.
(Credit:
ONR)
In what it says is a "first of its kind" initiative, the U.S. Navy plans to launch sometime this spring an unmanned aerial vehicle for a 24-hour endurance flight carrying a 5-pound payload and powered entirely by a hydrogen-powered fuel cell.
Called the Ion Tiger, the UAV can travel farther and carry heavier loads than earlier battery-powered designs, according to the Office of Naval Research. It also boasts "stealthy characteristics" such as reduced noise, low heat signature, and zero emissions (PDF).
"This will really be a demonstration for a fuel cell system in a UAV application," ONR Program Manager Dr. Michele Anderson said. "That's something nobody can do right now."
Fuel cells convert hydrogen and oxygen into water in a pollution-free process to create an electrical current delivering up to double the efficiency of an internal combustion engine, researchers claim.
The Tiger will use a "500-watt polymer fuel cell with a high specific power system." Weight will be reduced using high-pressure lightweight hydrogen storage tanks. The UAV has already "demonstrated sound aerodynamics, high functionality, and low-heat and noise signatures under battery-powered tests," according to ONR.
This test will show how a surveillance drone can operate economically with less possibility of detection and still exceed the duration of previous flights seven-fold.
Collaborators include Protonex Technology and the University of Hawaii.
(Credit:
Alion Science )
The U.S. Navy has selected two companies to develop a Transformable Craft capable of ferrying heavy tanks from ships at sea, through the surf, and onto beachheads around the world.
The Office of Naval Research (ONR) wants a T-Craft that does 40 knots, carries at least six tanks, and is able to survive 57-knot winds and 60-foot waves. It must also mitigate wave motion, to allow the transfer of vehicles from one ship to the other while rocking on the high seas.
To accomplish that, the companies Alion Science and Umoe-Mandal will need to develop and deploy some combination of new propulsion system, experimental hulls, exotic composites, "variable-geometry" bows that adjust to different dock set-ups, and retractable skirts for under-hull air cushions.
Also, the thing has to float. So ONR will be scrutinizing seal design (PDF).
"The T-Craft ship supports the rapid transfer of Army and Marine Corps equipment ashore," said retired Vice Admiral Scott Fry, vice president of Alion. "This is game-changing technology. This capability does not currently exist. This ship can go across the ocean and link up with a large logistics ship and take on some of the roll-on, roll-off cargo, and then land it on the beach."
The Sea Base Connector Transformable-Craft program is an integral part of the military's "sea basing" concept (PDF), in which floating bases fill-in where land bases are unfeasible or real estate prices are just too high. This would allow U.S. forces to reduce reliance on foreign ports, friendly or otherwise (PDF).
The transformer will be able to operate in four modes: from "open ocean transit" to an amphibious mode that can negotiate sand bars and mud flats.
This is phase II of the program. The companies will build full scale models for evaluation and testing. The best design may go on to full production in Phase III.
(Credit:
ONR)
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