Meet the bat bot
New design for autonomous robot takes its inspiration from bat echo-location. Andrew Masterson reports.
Israeli researchers have designed a new type of robot with a navigation system that mimics the echo-location abilities of bats.
The fully autonomous machine, dubbed the “Robat”, was built by a team headed by Itamar Eliakim from Tel Aviv University, and is revealed in the journal PLOS Computational Biology.
Many species of bat, famously, have poor vision, and rely on sound to navigate quickly and successfully in the dark. They do so by emitting a series of high-pitched noises, and listening to their echoes.
By processing these signals they are able to quickly determine the three-dimensional reality of their immediate environment and avoid any obstacles, even when moving at high speed.
Eliakim’s Robat promises to do exactly the same thing – albeit while staying firmly on the ground and moving by means of four thick-tyred wheels – using exactly the same mechanism.
The machine features an ultrasonic speaker that emits frequency modulated chirps at a rate similar to that used by bats. The returning echoes are then picked up by two ultrasonic microphones that essentially function as ears. The system requires no visual input.
By running the returning sounds through an artificial neural network, the Robat is able to rapidly map the borders of objects in its environment. The results are detailed enough that it is able to distinguish between an impenetrable barrier, such as a wall, and a partial obstacle, such as the leaves of a plant, through which it is able to push.
“Unlike most previous attempts to apply sonar in robotics, we focus on a biological bat-like approach, which relies on a single emitter and two ears, and we apply a biological plausible signal processing approach to extract information about objects’ position and identity,” the researchers state.