New robotic 'bat' uses sound to map unique environments

Scientists have developed 'Robat' -- a fully autonomous terrestrial robot with bat-like qualities that uses echolocation to move through novel environments while mapping them based only on sound.

Bats use echolocation to map novel environments, navigating them by emitting sound then extracting information from the echoes reflected by objects in their surroundings, said researchers from the Tel Aviv University (TAU) in Israel.

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, according to the research published in the journal PLOS Computational Biology.

TAU graduate student Itamar Eliakim developed the robot that uses a biological bat-like approach, emitting sound and analysing the returning echoes to generate a map of space.

"Our Robat is the first fully autonomous, bat-like bio-robot 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," said Eliakim.

"We've been able to demonstrate the great potential of using sound in future robotic applications," Eliakim said.

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.

It 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, researchers said.

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, they said.