Robots go under the seas
2 Bay State firms' devices help the Navy clear mines from the ocean more safely and efficiently
With the twist of a knob, electronics technician Erik White sent a burst of sonar into the water just west of Bassetts Island off Pocasset. About 20 feet from the boat where White stood, a small bright yellow watercraft came to life.
A spray of water burst from the vessel's tail as its propeller spun up. It surged forward, creating a miniature wake. Suddenly, it sank -- just as it was supposed to.
The REMUS 100 has gone hunting for submerged mines, the kind that could vaporize any boat in this peaceful harbor, or open up the belly of a warship in the Persian Gulf. It's the ideal task for an autonomous underwater vehicle, or AUV -- basically, a self-guided seagoing robot. REMUS -- the name stands for Remote Environmental Measuring UnitS -- was born from research at Massachusetts' famed Woods Hole Oceanographic Institution.
In 2001, Christopher von Alt, former principal engineer at Woods Hole, joined with colleagues to commercialize the REMUS technology. Von Alt's company, Hydroid LLC of Pocasset, has sold about 130 REMUS machines, most of them to the US Navy.
"REMUS was the first AUV that was certified by the Navy for use as a weapon of war," said von Alt. The navies of Great Britain, Australia, and New Zealand also use them.
Massachusetts has a strong land-based military robot industry, thanks to companies like iRobot Corp. and Foster-Miller Inc. The role locally developed robots play in helping patrol the seas is less well known, but these underwater sentries have already proved their worth in combat operations.
"We use them quite frequently now," said Landon Hutchens , public affairs officer for the Navy's Naval Sea Systems Command in Washington. "They work very well and make clearance of underwater mines and other things more rapid and more efficient."
In 2003, during the invasion of Iraq, US Navy special warfare teams used several of the REMUS robots to scour the port of Umm Qasr for mines with high-resolution sonars. Even when they find nothing, robots like the REMUS free up Navy personnel for other, safer tasks. The goal, said the Navy's Hutchens, is to "keep the man out of the minefield."
REMUS doesn't swim alone; in Cambridge, Bluefin Robotics Corp. produces a competing line of undersea robots, based on technology developed for the Navy at the Massachusetts Institute of Technology.
Bluefin has sold about 50 units, mostly to the US Navy. The two companies make a range of seagoing robots, priced from $350,000 to $2.5 million and capable of diving as deep as 18,000 feet. Both Bluefin and Hydroid are privately held companies and don't reveal their finances. But both say they're making a profit, and Hydroid says its sales are growing at more than 30 percent per year.
Most land-based robots must be remotely controlled by a human being. But you can't broadcast radio signals through water, and only very simple commands can be sent through sonar pulses. Essentially, underwater robots are on their own. They must be smart enough to find their own way to their destination, carry out their missions, and then bob to the surface to transmit data or ask to be picked up. It's a tall order, but Hydroid's machines manage with surprisingly crude technology. "It's commercial off-the-shelf technology with a wrapper around it," said von Alt.
The REMUS's main processor chip is an Intel 486, developed for the desktop computers of the late 1980s. Its operating system software is even more archaic: Microsoft's MS-DOS, developed in 1981. Yet these relics of computing's Dark Ages are more than adequate for the task.
Still, REMUS has plenty of high-end technology, including an inertial navigation system, GPS satellite receiver, a WiFi wireless Internet system, and a link to the Iridium satellite telephone network, allowing a REMUS to phone home from nearly any spot on earth. It's all packed inside a torpedo-shaped pressure hull that keeps inner components dry.
Bluefin uses a different structural approach, one that relies on the toughness of many electronic components. When a Bluefin robot is submerged, water flows inside the device, equalizing the pressure inside and out. Electronic components are sealed in plastic packages filled with a liquid that doesn't conduct electricity. Components are chosen for their ability to withstand high pressure.
Chief operating officer Robert Grieve said this enables Bluefin to use a modular approach. There's no need to dismantle a pressure hull during repairs; just snap out the defective electronics packet and snap in a new one. "They can just send us back the failed module and we repair it and send it back," Grieve said.
Both Bluefin and Hydroid have civilian customers, such as oil companies surveying the seas for good places to drill. Universities use robots to conduct both academic and military research.
Mark Moline, professor of biology at California Polytechnic State University in San Luis Obispo , uses two Hydroid REMUS robots to track the spread of toxic "red tide" algae in the ocean. "We can spot it and track it now," said Moline. He also works with the Navy to study bioluminescence -- the glow emitted under certain conditions by tiny aquatic creatures. This glow can give away the position of a landing party during a commando raid, and the Navy is trying to find out how to minimize the risk.
Despite Hydroid's success with the Pentagon and academia, von Alt wants more. He thinks the oil industry should buy more robots to survey routes for underwater pipelines, or to inspect existing ones. Telecom companies could use them for construction and maintenance of undersea cables.
Von Alt says cautious executives have been slow to fully exploit undersea robots, but he's convinced the tide is starting to turn. "The people in the boardrooms are starting to accept this idea," he said. "Once one guy does it the other guy has to do it, and that blows the doors open."
Hiawatha Bray can be reached at email@example.com.