Teresa Escrig

News and oppinion about Cognitive AI & Robotics

Autonomous Underwater robots – another very active market area for robotics

leave a comment

With the ultimate goal of designing completely autonomous robots that can navigate and map cloudy underwater environments without any prior knowledge of the environment and detect mines as small as 10 cm in diameter, researchers at HoverGroup (MIT) have came up with algorithms to program a robot called the Hovering Autonomous Underwater Vehicle (HAUV).

To provide a detailed sweep of a ship’s hull, the researchers took a two-stage approach. Firstly, the robot is programmed to swim in a square around the ship’s hull at a safe distance of 10 meters (33 ft), using its sonar camera to gather data that is used to produce a grainy point cloud. Although a ship’s large propeller can be identified at this low resolution, it isn’t detailed enough to make out a small mine.

Additionally, the point cloud may not necessarily tell the robot where a ship’s structure begins and ends – a problem if it wants to avoid colliding with a ship’s propellers. To generate a three-dimensional, “watertight” mesh model of the ship, the researchers translated this point cloud into a solid structure by adapting computer-graphics algorithms to the sonar data.

Once the robot has a solid structure to work with, the robot moves onto the second stage. This sees the robot programmed to swim closer to the ship, with the idea of covering every point in the mesh at spaces of 10 centimeters apart.

Read more >

US Navy is also developing autonomous underwater hull-cleaning robots. The Robotic Hull Bio-inspired Underwater Grooming tool, or Hull BUG, is being developed by the US Office of Naval Research (ONR) and SeaRobotics.

The Hull BUG has four wheels, and attaches itself to the underside of ships using a negative pressure device that creates a vortex between the BUG and the hull. Much like a robotic vacuum cleaner, lawnmower or floor cleaner, the idea is that once it’s put in place, it can set about getting the job done without any outside control.

Onboard sensors allow it to steer around obstacles, and a fluorometer lets it detect biofilm, the goop in which barnacles and other greeblies settle. Once it detects biofilm, powerful brushes on its underside are activated, and the film is scrubbed off. In this way, it is intended more for the prevention of barnacles, than for their removal. Initial tests have shown it to be very effective.

Read more >

Leave a Reply