First step in navigation software for underwater robots
On the water, cruising along with no paddles or people in sight, the kayaks look like the evidence of a day trip gone wrong. But one day, small robotic vessels like these, piloting themselves and loaded with high-tech gadgetry, could bring supplies to tsunami survivors or search for hidden explosives in coastal waters.
The kayaks, called SCOUTs (surface craft for oceanographic and undersea testing), are meant to help the navy develop navigation software for underwater robots. The navy envisions a day when swarms of autonomous submarines sweep the ocean floor for mines. Because it is very difficult for vessels to communicate with each other underwater, a team including Joseph Curcio and John Leonard, of MIT’s Center for Ocean Engineering, and navy scientist Michael Benjamin suggested first developing the navigation software for surface craft–kayaks equipped with GPS, Wi-Fi, and radio antennae. They proceeded to outfit several plastic boats–bought off the shelf for $500 each–with battery-operated propellers, computers sealed in watertight compartments, and communications gear. Leonard likens the work to “using training wheels to learn how to ride a bike.”
There are 10 SCOUTs in operation, including four owned by the navy. In one experiment, three of the 10-foot-long boats fall into a triangular formation, like a tiny flock of migrating birds, with the two trailing vessels determining their positions and headings based solely on information from the lead boat. “Wherever he goes, they go,” says Curcio. The researchers are working on using undersea acoustical information to achieve the same result.
In the course of developing the robotic kayaks, the group has imagined a slew of other applications. Curcio designed a winch for a sensor that can be lowered hundreds of feet below the surface and dragged behind a kayak to monitor ocean conditions such as temperature and salinity. Leonard adds that with the development of the SCOUT, “there’s a whole new set of robots for humanitarian missions.” Hundreds of kayaks could be dropped from an aerial transport into the water along a tsunami-flooded coastline. Programmed to head for specific destinations, they could deliver medical supplies or, if outfitted with wireless routers or mini cell-phone towers, reëstablish mobile-communications networks.
The researchers have begun to apply many of their ideas to robotic submarines, but they say it will be a few years before large groups of them can operate together.