Estonian Turtle-Robot Searches for Shipwrecks and Treasure

The unique feature of the U-CAT, about the size of a vacuum cleaner, is four silicon flippers inspired by streamlined sea turtles’ arms and legs

In this photo taken on Wednesday, Nov. 25, 2015, Taavi Salumae, designer of the U-CAT robot and researcher at the Biorobotics Centre at the Tallinn University of Technology, prepares the U-CAT robot for testing in an aquarium in Tallinn, Estonia. AP Photo/Vitnija Saldava

TALLINN, Estonia—The Baltic seabed, littered with war debris and shipwrecks, has fascinated historians and researchers through the ages. But the underwater search robots they use pose problems by further disturbing the silty waters with their propeller movements.

Estonian engineers say they may have found a solution with their latest invention — a small, propeller-less underwater robot that causes minimum disturbance and lowers the risk of damage to submarine archaeology.

In this photo taken on Wednesday, Nov. 25, 2015, Taavi Salumae, designer of the U-CAT robot and researcher at the Biorobotics Centre at the Tallinn University of Technology, tests the U-CAT robot in an aquarium using a fish net in Tallinn, Estonia. AP Photo/Vitnija Saldava