On their own, ants are limited in both strength and intelligence. As a colony, however, they can employ complex strategies to take on sophisticated tasks and evade larger predators.
It is not surprising, then, that robotics researchers at Ecole Polytechnique Fédérale de Lausanne (EPFL) have used this phenomenon as inspiration to develop tiny “robot-ants” able to communicate with one another and work collectively. Despite their simple design and weight of only 10 grams, each robot possesses multiple locomotion modes to navigate any type of surface. When working together, they can quickly detect and overcome obstacles and move objects much larger and heavier than themselves.
The robot-ants, also known as Tribots, are three-legged, T-shaped origami robots. They can be assembled in only a few minutes by folding a stack of thin, multi-material sheets, making them suitable for mass production. The Tribots use infrared and proximity sensors for detection and communication purposes, and could accommodate more sensors for different applications.
Specifically, the movements of the Tribots are modeled on six-legged members of the genus Odontomachus, also known as trap-jaw ants. According to Zhenishbek Zhakypov, first author of a study published in Nature, the ants snap their powerful jaws together to catapult themselves away from predators. The Tribots’ origami design allows them to replicate this ability with multiple shape-memory actuators. A single robot-ant can thus produce five distinct locomotion gaits: vertical jumping, horizontal jumping, somersaulting to clear obstacles, walking on textured terrain and crawling on flat surfaces — just like their living counterparts.
In addition, each robot-ant is assigned a specific role to handle a variety of situations. Professor Jamie Paik, whose laboratory directed the research, explained that “explorers” detect physical obstacles in their path and inform the rest of the group of their findings. A “leader” then gives instructions while “workers” pool their strength to move objects.
"Each Tribot, just like Odontomachus ants, can have different roles,” said Paik. “However, they can also take on new roles instantaneously when faced with a new mission or an unknown environment, or even when other members get lost. This goes beyond what the real ants can do."
Thanks to their ability to work untethered and with complete autonomy, that could include tackling emergency search missions. Their multi-locomotive and multi-agent communication capabilities would enable them to locate a target quickly over a large surface without the need for visual feedback or GPS. "Since they can be manufactured and deployed in large numbers, having some 'casualties' would not affect the success of the mission," added Paik. “For certain missions, they would outperform larger, more powerful robots."