Researchers build robotic turtle for exploring shipwrecks

A team of researchers has built a robotic turtle to enter and explore deep-sea shipwrecks. Called the U-CAT , the robot is designed to emulate the underwater movements of sea turtles.

The U-CAT is propelled by four independently-moving flippers that enable it to swim up, down, forward, and backward. The robot can also turn and change direction on the spot.

Additionally, the U-CAT doesn’t have a tether, making it free it to travel longer distances and get to hard-to-reach places. The researchers specifically designed the robot to have a high level of maneuverability, in order to make it possible for the turtle to explore confined underwater spaces with ease.

“U-CAT is specifically designed to meet the end-user requirements,” said Taavi Salumäe , a researcher from the Center for Biorobotics in Tallinn University of Technology who designed the U-CAT. “Conventional underwater robots use propellers for locomotion. Fin propulsors of U-CAT can drive the robot in all directions without disturbing water and beating up silt from the bottom, which would decrease visibility inside the shipwreck.”

Cheaper than hiring mutant ninjas Maneuverability isn’t the U-CAT’s only key feature, though. According to Maarja Kruusmaa, head of the Centre for Biorobotics, the robot turtle is also relatively inexpensive to produce. Kruusmaa admits that while the turtle is designed to be able to get out of tight spots underwater, the possibility of it getting stuck or lost still exists. Since the U-CAT is a cost-efficient machine, Kruusma reasoned, replacing a lost or malfunction U-CAT “won’t bankrupt the archaeologist.”

The U-CAT is also equipped with an underwater video camera, allowing researchers to use footage to reconstruct underwater sites.

Robots, robots everywhere:
Underwater robots aren’t exactly a new innovation – such machines are already being used in the oil and gas industry, as well as for military operations. However, current shipwreck explorations are still being carried out by human divers – a time-consuming, expensive, and perilous venture for them. The U-CAT is designed to be a suitable and inexpensive alternative.

"The so called biomimetic robots, robots based on animals and plants, is an increasing trend in robotics where we try to overcome the technological bottlenecks by looking at alternative technical solutions provided by nature," explained Kruusmaa.

The U-CAT is a product of the ARROWS research project, an EU initiative funded and established to develop technologies for underwater archaeologists and explorers. The U-CAT will first be tested in the Baltic sea, after which it will work with bigger robots and human divers in the Mediterranean. Dr. Sebastiano Tusa, an underwater archaeologist from Sicilian Regional Government, said that the U-CAT “would work in cooperation with larger underwater robots and together with image recognition technologies for discovery, identification and reconstruction of underwater sites, would facilitate the work in all phases of an archaeological campaign.”

The robot will be on display at the Robot Safari in the London Science Museum from November 28 to December 1. The team will also show a demonstration involving downscaled U-CATS operating inside an aquarium at the exhibit.