I, RAnt

​You’ve probably seen or at least heard of Terminator, right? Killer robots, violence, decimation of humans? Now, can you imagine if those robots were lowly ants? Although individual ants can’t accomplish all that much on their own, a collective group of them can achieve surprising feats. Researchers are operating on that premise to build groups of cooperative robots capable of completing complex tasks. Will these robots be the end of humanity as we know it? Thankfully, probably not. The real story, although less violent, is still interesting—so read on to find out more!

Simple Robots, Complex Abilities

Eusocial insects work cooperatively, divide labor, and live in elaborate nests constructed by colony members. This cooperative action allows social insects to solve complex problems that they likely could not solve individually. Harvard researchers became interested in this phenomenon and were curious as to how insects manipulate their environment to create complex, functional architecture. They began by investigating the behavior of carpenter ants and their ability to, as a team, escape from a soft “corral”.
 
Researchers watched the ants behave inside of these ‘corrals’ and noted that before trying to escape, the ants wandered around at random and talked to one another using their antennae. Insect antennae are comprised of a number of specialized cells that allow them to interact with their environment in all sorts of ways. They are predominantly used for smell. Using antennae to interact and communicate with other insects is called antennation. The authors saw many ants engaging in antennation before they started working together. Once a few ants got together and started excavating, more and more ants started arriving. Eventually, excavation at this point started proceeding faster than in other areas, allowing ants to tunnel out. Mathematical models of this behavior showed that ants can only successfully get out of a corral when they i) work together sufficiently strongly while ii) excavating together efficiently.

Eusocial insects, such as ants, bees, wasps, and termites, cooperate to achieve some pretty amazing results. For example, insect nest construction, like the one you see above, is a striking result of colony cooperation. (Image Credit: Insects Unlocked, Image Source: Wikimedia Commons)

Making Robot Ants, or "RAnts"

Building upon their mathematical models, researchers constructed robot ants to see if they could also communicate and cooperate in the same way. They used “photoromones” instead of pheromones, to initiate robot behavior. Photoromones are fields of light that researchers used to mimic antennation and chemicals that ants use to communicate with each other. They programmed the RAnts to follow the gradient of a photoromone, avoid other ants where the photoromone density was high, and to pick up obstacles where photoromone density was high, and move them to an area where density was low. With this code, RAnts were able to successfully, and quickly, escape confinement.

Maybe it is time we start reimagining what “robots” can look like, or at least ask if a team of RAnts could take on Skynet…? (Image Source: Publicdomainpictures.net).

Conclusions

​This study revealed that even complex events and behaviors stem from simple rules. The ability of the robots was robust— even if a few ants failed, the team could still complete the task correctly. These findings may contribute to the field of AI and robotics, where engineers that input simple, reinforceable rules could build a team of robots capable of achieving grand outcomes. The work will also help humans better understand the evolution of cooperative behavior in animals. All around, some high-level findings resulting from some very tiny insects!