SUNNYVALE, Calif. --- Liquid Robotics experienced its first shark attack recently. Everything came out great.

The company -- which announced today it has raised $22 million in a fourth round from oil services giant Schlumberger and VantagePoint Venture Partners -- builds and manages semi-autonomous robots that effectively serve as the eyes and ears on the high seas for government agencies, fisheries and oil companies.

The Wave Glider robots can help count fish stocks, for instance, or trace the path of hydrocarbons in the event of an oil spill, making cleanup easier. It’s a green technology and an example of “extroverted computing,” because we really don’t have an economic or persistent technique for monitoring activities that take place offshore. (See video.)

“It will cost you $30,000 to $70,000 a day plus fuel to keep a ship at sea,” said Bill Vass, Liquid’s CEO and a Sun Microsystems alum. “You can send one of these things out to the middle of the Pacific for two and a half years.”

Another application: the company is currently negotiating with government officials to possibly deploy a flotilla of Wave Gliders to ring an aquatic nature preserve in Hawaii that is currently beset by poachers. The robots would send warning signals to the Coast Guard about boats entering the area and take photos of the interlopers.

A basic robot runs about $100,000, while one rigged with acoustic sensors and other complex equipment can go for as high as $500,000.

While the machines guide themselves to some degree, pilots in Sunnyvale manage the craft in tricky situations and keep an eye out for any possible mishaps. That guy with the beard and a coffee cup in the cubicle at the front of the office is essentially an admiral.

Wave Gliders don’t use fossil fuels. The onboard radios, cameras and other electronics are powered bysolarpanels, while the robots are propelled forward by wave power, which also makes them one of the first commercial examples of a viable wave power application.

The vehicles don’t convert wave motion into electricity. Instead, fins seven meters below the floating surface platform undulate to propel the vehicles forward. It is similar to how a scuba diver (or a whale or a porpoise) moves forward by undulating fins. The fins push against a mass of water. The videos show the fins right beneath the platform: in the water, they telescope down to create 21 feet of distance from the surface.

Liquid drops the robots off about a mile from shore and lets them swim to their destination.  “It takes 122 days to cross the Pacific,” he added. “[The device] takes the up-and-down motion of the waves and coverts it into thrust.”

Waves as small as one inch in height provide enough energy to move the craft at a speed of one-tenth of a knot, but in high seas, the pace can be upped to a somewhat fast three to four knots. The machines also have safety mechanisms to prevent damage in storms. During one voyage to Alaska, the robots endured 22-foot high waves and survived.

The company has approximately 60 craft out in the ocean and cumulatively has logged 150,000 ocean miles.  The surprising thing about the shark attack -- which left a few scrapes on the device in its wake -- was that it took so long to happen. Four of the vehicles are currently working 200 miles offshore in the Gulf of Mexico.

Currently, Liquid has a mixed business model. Oil companies, for instance, buy monitoring as a service. Governments tend to buy the craft outright and then co-manage operations with Liquid.

Ideally, the company will become a cloud computing service, managing its own fleet of vehicles that can be deployed to provide data to whomever needs it. Oil companies, for instance, could conceivably pay for live data monitoring for oil rigs. If Liquid could get them to pay $500,000 per rig per year, that alone would bring in $3 billion in annual revenue.

The company is currently negotiating a contract with the national navy of New Zealand, which only has two ships. The robots would help with environmental and security issues. Another possible application for sea bots: small versions of the Wave Glider could be dropped out of planes after an accident to comb an area for survivors. Hundreds of small robots could more efficiently cover an area than a few isolated search boats.

Relay stations for satellites? Sure. You could put cell towers in the ocean too to help out stranded craft.

Robots on the high seas, of course, also present thorny legal questions. Could a group or government hostile to the U.S. buy a set of these and ring New York Harbor? It’s not part of the business plan, but one could see a company (maybe not Liquid) coming up with an application like that.

The security question, of course, goes both ways. The U.S. government is looking at the technology to see if it could be deployed as a trip wire for drug smugglers traveling between Cuba and Florida. Some smugglers have begun to employ diesel subs to make it to the U.S.  Sensors on a robot could detect engine noise and send out a warning to the authorities.

Robots  don’t fit within the law of the sea easily. A vessel is defined as a craft that carries people or cargo. Thus, these aren’t vessels. In fact, they are more like marine debris under the law, which implies that sailors could pick them up and take them home as salvage.

“None have been stolen yet,” he said. Future versions, however, may contain two-way radios so Sunnyvale employees can explain what’s going on to mystified sailors.