Robots Could Replace Humans in Dangerous Ocean Missions
Digital warscapes populated by drones will soon see aquatic newcomers: undersea robots able to autonomously patrol ocean spaces for weeks.
Autonomous and programmed robots referred to as UUVs, for "unmanned undersea vehicles" presently are used by the Navy to conduct surveys for ocean science and sonar mapping. New software that grants autonomy to certain bots known as gliders will dramatically boost the Navy's ability to conduct reconnaissance of large undersea areas.
"We have examined the capabilities provided by UUVs over the past several decades and determined that they are particularly suitable for many of the traditional naval missions," said Bob Freeman, speaking for the Navy Office of Oceanography. "Specifically, they are well-suited to the 'dull, dirty and dangerous' missions."
"Radio does not work in water. You cannot have Wi-fi in water," explained principal investigator Daniela Rus at the Massachusetts Institute of Technology.
"If you want to communicate in water, you must use acoustic communication, which travels at 300 bits a second and we are used to megabits."
Higher power needs and signal speeds that are six to seven orders of magnitude slower than in the air make human/undersea robot communication impractical, Rus added.
An innovative algorithm uniquely suited to the zigzag motion of some sea bots allows them to work autonomously by a logic called "persistence path planning." Like a security camera that screens a room more frequently when it is filled with people, the framework promotes a robot's visit to locations undergoing more change, Rus said.
In recent tests of gliders involving three- or four-week tours of California waters, a glider equipped with the new software produced "two to four times as many sampling profiles in areas of high interest" as a conventional glider patrolling the same circuit, scientists said in a statement.
Gliders are self-propelled vehicles that operate by buoyancy. They are of great interest to the Navy because, unlike other robots, they have endurance for long-term missions, Freeman said.
The gliders in the tests, made by Webb Research Corp., were torpedo-shaped: 1.5 meters (5 feet) long and 21.3 centimeters (8 inches) in diameter.
Touring Monterey Bay and a marine environment in Southern California, the glider with the new software discovered a red algae bloom and monitored the spread of pollutants.
"The interesting thing is the robot worked autonomously without human input for many days, but it was also able to change and adapt its path to things it deemed interesting in the environment," Rus said.
The robot's tirelessness and its ability to act on its assessments make it a viable substitute for crewed platforms in missions that involve contaminated environments, radiological hazards, minefields, and submarine battle spaces, Freeman said.
"These systems will provide autonomous undersea support to Navy warfighters. Within this decade, we will move to a Large Displacement UUV for extended operations across several mission areas," he said.