The “Robat” is a fully autonomous, four-wheeled terrestrial robot with bat-like qualities that uses echolocation, also called bio sonar, to move through novel environments while mapping them based only on sound. It was developed at Tel Aviv University (TAU).

Bats use echolocation to map novel environments, navigating them by emitting sound then extracting information from the echoes reflected by objects in their surroundings. Many theories have been proposed to explain how bats harness sonar in order to navigate, but few attempts have been made to build a robot that mimics a bat’s abilities.

A TAU study about the invention was published in PLOS Computational Biology.

TAU graduate student Itamar Eliakim developed a robot that uses a biological bat-like approach, emitting sound and analyzing the returning echoes to generate a map of space. Prof. Yossi Yovel of TAU’s Department of Zoology and Dr. Gabor Kosa of TAU’s School of Mechanical Engineering serve as Mr. Eliakim’s advisors.

The Robat is equipped with an ultrasonic speaker that produces frequency-modulated chirps at a rate typically used by bats, as well as two ultrasonic microphones that serve as the robot’s ears. The time delay of the echo tells Robat how far away objects are.

Robat classifies the borders and shapes of the objects it encounters with an artificial neural network, creating a rich, accurate map of its environment while avoiding obstacles. For example, when reaching a dead end, the robot uses its classification abilities to determine whether it is blocked by a wall or by a plant through which it could pass.

To test Robat, the researchers placed it in a greenhouse in a botanical garden. Robat then drove through the environment avoiding obstacles, drawing a map of the surroundings along the way.

“Our Robat is the first fully autonomous, bat-like biorobot that moves through a novel environment while mapping it solely based on echo information. This information delineates the borders of objects and the free paths between them,” says Eliakim. “We’ve been able to demonstrate the great potential of using sound in future robotic applications.”

They add that Robat could be useful in situations where visibility is limited, such as search and rescue missions or while moving in extreme weather.

Editor’s Note: This article was republished from Tel Aviv University.