In 2020, Néstor O. Pérez-Arancibia, an associate professor of engineering at Washington State University (WSU), developed a tiny, autonomous robot beetle capable of using combusting methanol to roam about. Now WSU has announced that Pérez-Arancibia’s “Robeetle” is officially the world’s smallest crawling robot. According to none other than Guinness World Records.

A yellow and black robot beetle standing on a green leaf.

IEEE Spectrum

Laughing Squid reported on the Robeetle’s new world title, which is clearly well deserved. The Robeetle, as WSU reports, weighs only about 88 milligrams. That’s a weight equivalent to approximately three grains of rice. And not much heavier than many types of real beetles.

The Robeetle, as the IEEE Spectrum video below shows, works using methanol combustion (methanol is a type of alcohol) to drive the locomotion of artificial muscles. The combustion process, which uses a chemical catalyst to oxidize the methanol, releases heat. The heat, in turn, changes the shape of nitinol wires in the Robeetle’s functional front legs. The nitinol wires, thanks to their ability to exhibit the “shape memory effect,” change back to their original shape when cooled. By heating and cooling its own nitinol legs continuously, the Robeetle’s able to roam autonomously.

While the Robeetle may seem like it has limited use, its list of capabilities—present and future—is long. Pérez-Arancibia and his colleagues show for example how the Robeetle can carry 2.6 times its own body weight. (Multiply that by a few thousand Robeetles and you’re really crankin’.) Plus the researchers can add a wireless RFID chip onto the Robeetle allowing it to become a mini gate opener.

IEEE Spectrum

Looking forward Pérez-Arancibia says he hopes researchers will be able to use his Robeetle to solve hard engineering problems. And emulate “talented” creatures such as squid or mice. Because, apparently, figuring out how to get robots to “seamlessly squeeze themselves like liquid” into tight places is an important goal in robotics. This makes us think Pérez-Arancibia should really make a Rocat next.