INNOVATION

Who Needs a Driver? These Navy Boats Are Programmed to Swarm Like Bees

Using algorithms based on the swarming behavior of ants and bees, the U.S. Navy is turning to driverless boats to protect its ships

Randy Rieland

October 14, 2014

The U.S. Navy expects to have swarm boats in operation as soon as next year. Office of Naval Research

This August, on the James River in Virginia, the U.S. Navy staged the kind of scene you’d expect to see at the beginning of a James Bond movie. As a large ship moved through the water, a helicopter overhead spotted an unidentified boat approaching and sent a warning to a small fleet of escort boats. Some were armed with loudspeakers, others with flashing lights, another with a .50 caliber machine gun.

Once the fleet zeroed in on the threatening vessel with radar and infrared sensors, some of the escort boats broke away and quickly encircled it. They flashed lights and blasted warnings through loudspeakers. Threat resolved.

All of the escort boats were unmanned—and yet they moved together as a group, thanks to what’s known as “swarm intelligence.”

A different kind of drone

This doesn’t mean the boats were programmed to move in unison like some kind of mechanical synchronized swimmers. Instead, each one relied on algorithms based on swarm behavior and then used radar to calculate its own route through the water, not only to avoid obstacles, but also to keep track of the locations of the other boats. The software, called Control Architecture for Robotic Agent Command and Sensing, or CARACas, allowed the boats to react to changing conditions, weigh the cost and benefits of different routes and collaborate with the other boats, all in the midst of chaos.

It sounds impressive and even better, it doesn’t cost that much, at least not in the realm of military spending. The small device that directs a boat’s movement within the swarm costs about $2,000 and can be fitted on any vessel. The Navy would install the equipment on inflatable boats it already has in its fleet. Also, this approach would dramatically reduce personnel needs. Providing that kind of escort for a ship would ordinarily require as many as 40 people, according to the Navy; only one person was necessary to direct the swarm exercise.

One thing an autonomous boat can’t do, though, is fire a weapon on its own. In line with a 2012 Department of Defense directive, the decision to fire a weapon on any U.S. military robotic device must be made by a human.

All together now

The idea that the swarming behavior of ants or the flocking of birds could be applied to inanimate objects goes back almost 25 years to research by University of California scientists Gerardo Beni and Jing Wang. They concluded that artificial intelligence algorithms could make mechanical devices respond to rewards, threats or changes in the environment and that breakthrough could result in an overall intelligence for a “swarm” of machines.

The approach was incorporated into the design of Curiosity, the Mars rover, with the purpose of giving it the intelligence to make decisions on its own based on what it encounters instead of waiting for instructions from Earth. That’s just one robot operating on its own, but others have suggested that one day a swarm of smaller machines could be a more efficient way of exploring the planet, with some serving as “scouts” that return and upload new information that becomes shared intelligence.

Common knowledge

Back on Earth, the U.S. Army Research Laboratory (ARL) has been funding research into reconnaissance spy-bots for years now, and swarm intelligence is being integrated into how they function. It’s part of a research project called Micro Autonomous Systems and Technology, the purpose of which, according to an Army spokesperson, is to enable “the autonomous operation of a collaborative ensemble of multifunctional mobile microsystems." In other words, swarming drones.

Vijay Kumar, a University of Pennsylvania scientist, is leading a research project that ARL has funded. His video of mini-drones, called quadrotors, flying in formation and then playing a theme song from a James Bond movie became a huge YouTube hit.

Kumar likes to point to potential non-military applications of swarming robots, such as leading search and rescue missions, say, to find lost hikers or injured people after a natural disaster. And the Navy says commercial versions of its swarm boats could provide security in shipping ports.

But based on where the bulk of the research money is coming from, the U.S. military is clearly taking the lead in developing autonomous machines that mimic swarm behavior. It probably was no coincidence that the Navy announced the success of the swarm boats exercise just before the 14th anniversary of the terrorist attack on the USS Cole, in October 2000. The Cole was attacked in a port in Yemen when a small boat packed with explosives and driven by a suicide bomber exploded next to the destroyer, blowing a 40-foot by 60-foot hole in the side of the ship. Seventeen American sailors were killed and 39 others were injured.

Rear Admiral Matthew Klunder, who is overseeing the swarm intelligence project as chief of naval research, made the connection in a press release: “While the attack on the Cole was not the only motivation for developing autonomous swarm capability, it certainly is front and center in our hearts and minds. If the Cole had been supported by autonomous USVs (Unmanned Surface Vehicles), they could have stopped that attack long before it got close to our brave men and women on board.”

The Navy expects to have the swarm boats in operation as soon as next year.

Here's one more swarming drones video to leave you with—1,000 swarming mini-robots, known as kilobots, developed by a team of Harvard University engineers.