Engineer Tom Austin removes REMUSa five-foot (1.5-meter) missile-like objectfrom a rack at the stern of the Zodiac and places it in the water. As the propeller begins to spin, REMUS dips its nose beneath the surface and its sleek lime-yellow body melts into the teal waters off of Woods Hole, Massachusetts. It then glides back and forth across the ocean floor on a ten-minute preset test mission under a harbor of unsuspecting sailboats.
Oceanographers are developing a new generation of unmanned subs for probing deep ocean and coastal waters. These Autonomous Unmanned Vehicles (AUVs), of which REMUS is one, are expected to be the fastest and cheapest tools to comb the oceans, collecting precise chemical, geological, and physical data.
Oceans cover more than 70 percent of the Earth's surface, yet less than 5 percent of their underwater landscapes have been explored.
Although current AUVs are launched and retrieved by ships, oceanographers anticipate that fleets of these craft will eventually launch from underwater docking stations and will transmit their data via telemetry in real time. "With AUVs always ready to go, the craft could respond immediately to special events like an underwater eruption or earthquake on the seafloor," says Dana Yerger, an AUV researcher at the Woods Hole Oceanographic Institution.
"The real thing that we're trying to get out of this is data," says Roger Stokey, of the Woods Hole Oceanographic Institution, and a senior engineer on the REMUS project. "The goal isn't to create an AUV, it's just a means to an end."
The REMote environmental sensing UnitS (REMUS) are at the cutting edge of AUV technology and are fully autonomous. Once REMUS is given a location and told what to measure, off it goes. There is no communication with it after that.
The greatest advantage to these small, unmanned craft is that they can work in temperature extremes from the Arabian Sea to Antarctica, and in conditions and for periods that would be perilous for divers.
Keen Interest Shown by U.S. Navy
Once the U.S. Navy got wind of REMUS' capabilities it wanted to harness the technology to roam hostile coastlines searching for buried mines.
"During the Gulf War, they had no way of bringing troops ashore via ships because they didn't know where the minefields were," says Stokey. "They'd send in SEALs (special sea-air-land forces) under the cover of darkness to feel around for these mines. Nobody in their right mind would want that job."
REMUS with its sleek, light body is perfectly adapted for swimming in coastal waters and is expected to play an integral role in upcoming projects to map the ocean floor of coastal regions.
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