IEEE Spectrum says, Forget Autonomous Cars—Autonomous Ships Are Almost Here.

My colleagues and I at Rolls-Royce anticipate that the first commercial vessel to navigate entirely by itself could be a harbor tug or a ferry designed to carry cars the short distance across the mouth of a river or a fjord and that it or similar ships will be in commercial operation within the next few years. And we expect fully autonomous oceangoing cargo ships to be routinely plying the world's seas in 10 or 15 years' time.

That people should be seriously interested in robotic ships is easy enough to explain: Such ships are expected to be safer, more efficient, and cheaper to run. According to a report published by the Munich-based insurance company Allianz in 2012, between 75 and 96 percent of marine accidents are a result of human error, often a result of fatigue. Remotely controlled and autonomous ships would reduce the risk of such mistakes and along with it the risk of injury and even death to crew members, not to mention the dangers to the ship itself.