- UC Berkeley Engineers develop an insect-sized robot with exceptional agility.
- The robot could move through a flat surface at a speed of about 1.5 miles an hour.
- The researchers tested the bot’s agility by putting it through a maze, which it completed in 5.6 seconds.
Robot with clever feet
Engineers at the University of California, Berkeley have developed an insect-like robot that can move rapidly and literally turn on a dime. The bot’s sophisticated footwork is because of its clever feet, which alternate stickiness and makes sharp turns by using different voltages.
The new robot is based on a concept reported by the researchers in 2019 and is composed of a rectangular sheet of polyvinylidene fluoride (PVDF) covered in an elastic polymer. When an alternate current is supplied, the material bends and straightens in rapid succession, resulting in forwarding motion.
The researchers demonstrated in a 2019 study that this simple model could be used to create a cockroach-sized robot that could scurry through a flat surface at a rate of 20 body lengths per second, or about 1.5 miles an hour — nearly the speed of living cockroaches and the quickest relative speed of an insect-sized robot. The main issue was that it wasn’t especially maneuverable, so engineers made it more sophisticated feet for the subsequent iteration.
“Our original robot could move very, very fast, but we could not really control whether the robot went left or right, and a lot of the time it would move randomly, because if there was a slight difference in the manufacturing process – if the robot was not symmetrical – it would veer to one side,” says Liwei Lin, senior author of the study. “In this work, the major innovation was adding these footpads that allow it to make very, very fast turns.”
The Maze Runner
The robot’s snazzy new feet operate on the theory of electrostatic adhesion – the same force that causes a balloon to adhere to your hair or clothes after rubbing it. When a voltage is supplied to one foot in this example, it sticks to the floor, causing the robot to spin abruptly in that direction.
The researchers tested the bot’s agility by putting it through a maze, which it completed in 5.6 seconds. In other experiments, it was outfitted with gas sensors and charged with generating a map of gas concentrations inside a certain region, which might foreshadow future uses in finding the source of leaks.
Senior author Liwei Lin stated, “One of the biggest challenges today is making smaller scale robots that maintain the power and control of bigger robots. With larger-scale robots, you can include a big battery and a control system, no problem. But when you try to shrink everything down to a smaller and smaller scale, the weight of those elements becomes difficult for the robot to carry and the robot generally moves very slowly. Our robot is very fast, quite strong, and requires very little power, allowing it to carry sensors and electronics while also carrying a battery.”