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Popular Mechanics
By David Hambling
How do you thwart the devastating efforts of terrorist divers? Develop a remote-control jet ski with poerful sonar and weapons, of course.

Take one jet ski, add a remote control and a sonar unit, and you have a new breed of robot warrior. While in harbor, warships make a tempting target for terrorists, because a single diver with an explosive charge can cause massive damage and loss of life. But a new robotic unmanned jet ski, known as Blackfish, may help even the odds. Developed by QinetiQ North America, in response to demand from the U.S. Navy's Underwater Warfare Centre, Blackfish belongs to a range of technology that includes sensors and weapons for "integrated swimmer defense."   

Operated remotely from up to a mile away, Blackfish is fast and maneuverable enough to intercept intruders. Harbor or fleet defenses will normally cover the entire area with powerful sonar, and Blackfish would then be dispatched to get a closer look and take action if necessary. Its high-resolution sonar and an underwater camera can distinguish divers from other objects, and it can carry a range of weapons for lethal and nonlethal response as required.   

Mark Hewitt, a senior vice president at Technology Solutions Group, an engineering and research and development group, says that Blackfish was built using off-the-shelf components. The jet ski was chosen as a lightweight, rugged platform that could be deployed easily, with a 40-knot speed (about 46 mph). It's smaller than a speedboat, and has the advantage of self-righting if it capsizes.


The primary underwater sensor on Blackfish is a Sound Metrics Didson imaging sonar that can acquire a clear picture of a diver from a hundred feet away. It's also outfitted with two cameras: one underwater with a light for illuminating darkness and another above the waterline to help pilot the craft.     

The main technical challenge, Hewitt says, was getting the jet ski to move slowly enough: "We couldn't get it to slow down to the speed of a swimmer." The problem was solved by adding bow thrusters, underwater propulsion jets that make Blackfish far more maneuverable than other jet skis. It can turn on its axis and perform precise movements, allowing it to stay close to a diver.

There are a number of armament options, though currently most revolve around nonlethal weapons to force an intruder to the surface. The Navy has developed devices that use intense sound; another possibility is light-based systems similar to laser dazzlers used by the Army. If lethal force is required, Blackfish could drop anti-diver grenades, which resemble miniature depth charges. In the longer run, Blackfish could be fitted with the weapons module from QinetiQ's MAARS ground robot, which can mount machines guns, 40-mm grenade launchers and other weapons. As this approach has yet to be tested, potential issues with aiming and recoil would have to be examined first.

At present, the Navy famously uses marine mammals, including dolphins and sea lions, for swimmer defense. Hewitt doesn't claim that Blackfish will be able to match their abilities (he wryly observes that after billions spent on bomb-detection technology, dogs are still the best bomb sniffers), but the jet ski will be much easier to deploy in a foreign port, and in a potentially dangerous situation it's preferable to send in a robot rather than an animal. (The Navy's dolphins are trained to jump into a boat after tagging a diver to keep them out of harm's way.)

Because Blackfish has a modular design, replacing or swapping out components is relatively straightforward—the underwater sensor unit attaches with eight bolts. This means it would be easy to outfit with different sensors or other gear. Hewitt suggests that with its shallow draught and good maneuverability, Blackfish might make a useful scout. Equipped with radar or other sensors, it could gather intelligence along beaches or rivers and check for mines or obstacles. Or it could be used to approach suspect vessels or floating objects without putting Coast Guard members in danger. Eventually, armed Blackfish might be useful for anti-pirate duties or for dealing with small boats like those deployed by Iran's Revolutionary Guard.

The production version will likely have onboard intelligence to avoid collisions. Other likely enhancements include networked operations, with connections to other Blackfish, manned vessels or even unmanned subs. QinetiQ North America expects the go-ahead for further engineering development of Blackfish from the Navy by the end of the year.

Original Article: http://www.popularmechanics.com/technology/military/robots/the-militarys-autonomous-jet-ski