High-performance naval warships and submarines rely on critical design factors such as top speed, acceleration and hydroacoustic stealth to achieve their mission. Biofouling of ship hulls, primarily caused by the buildup of marine crustaceans such as barnacles, adds weight, roughness and increases drag, reducing a vessels fuel efficiency especially for Navy ships as they move throughout the world's oceans.
The Naval Surface Warfare Center, Carderock, estimates that vessel speed is reduced by up to 10 percent from biofouling, which can require up to a 40 percent increase in fuel consumption to counter the added drag. In fact, colonized barnacles and biofilms settled on the hull of a Navy ship translates into roughly 500 million dollars annually in extra fuel and maintenance costs.
ONR is developing the robotic Hull BUG to prevent or suppress the growth of advanced biofouling. Hull BUG is an autonomous vehicle designed to groom and maintain the hull surfaces of ships. In some ways its mission is similar to a robotic home floor cleaner, lawn mower or some advanced pool cleaners in that it is designed to be tether free, autonomous and run on a battery for a significant duration of its mission. Once developed it is expected that the Hull BUG platform could also provide other capabilities such as hull inspection or force protection.
The Hull BUG is being developed in ONR’s Discovery and Invention (D&I) program. If successful the technology will be further developed through the Future Naval Capabilities program with full ship demonstrations in the 2015 timeframe.