Researchers claim they have created the first fully autonomous robot that navigates via ultrasound, just like a bat.
Bats survey their environment by emitting ultrasound chirps that boomerang off objects, an ability known as echolocation. The robot, known as Robat, does something similar. Larger than most bats, and without wings, it is based around an off-the-shelf four-wheeled robot. Robat produces ultrasonic chirps from a tiny speaker mounted above its front wheels. It listens for these sounds to echo back to it through two microphone “ears.” Robat processes and makes decisions based on this information using a small onboard computer.
When released into an obstacle course inside a large greenhouse containing plants and other objects, the robot was able to gracefully wheel through the environment without hitting anything, researchers report today in PLOS Computational Biology. It also mapped the 2D outline of the objects it encountered in real time, revealing obstacle-free paths that could be used on future journeys, much like a real bat.
Bats are also thought to use echoes to categorize objects and even identify particular objects, such as a favorite tree for foraging. Robat can do the same—almost. It was able to distinguish between plants and nonplants with 68% accuracy
Robat’s main flaw is that it has to stop every half a meter for about 30 seconds to gather information. But the researchers say that with a few modifications—such as a speaker with a wider beam—Robat should be able to echolocate on the move. Once perfected, the robot could be particularly useful in situations where visual systems might struggle, such as in search and rescue operations in smoke-filled buildings or at night—when bats are most active.