Termite robots have been designed to build complex structures.
"Termites are what inspired this whole research topic for us," the study's lead author Justin Werfel, a researcher at the Wyss Institute for Biologically Inspired Engineering in Cambridge, Massachusetts, said in an American Association for the Advancement of Science news release. "We learned the incredible things these tiny insects can build and said: Fantastic. Now how do we create and program robots that work in similar ways but build what humans want?"
Humans need elaborate blueprints in order to build complex structures, but termites have the ability to build complex mounds without prior planning. The insects do this by taking cues from each other and their building environment.
This type of building strategy is called "stigmergy," researchers studied this behavior and created algorithms in an attempt to mimic it.
The new robots need only to sense a nearby brick or fellow machine in order to plot their next move. They employ sensors to know where open spots exist to lay down bricks. The robots are implemented with a few basic rules.
"There are two kinds of rules," Werfel said. "The rules that are the same for any structure the robots build, and the 'traffic laws' that correspond to the specific structure. The [traffic laws] tell robots at any site which sites they're allowed to go to next: traffic can only flow in one direction between any two adjacent sites, which keeps a flow of robots and material moving through the structure."
"If they built carelessly, it would be easy for them to build in a way where they got stuck," he said. "The safety checks involve a robot looking at the sites immediately around itself, paying attention to where the bricks already are and where others are supposed to be, and making sure certain conditions in that local area are satisfied."
Even though each robot is programed with a few simple rules, when they work together they have the ability to create complex structures.
In order to build larger structures more robots can be added without reprogramming.
"A long-term vision is for robot teams like this to build full-scale structures for human use, maybe with particular utility in settings where it's difficult or dangerous for humans to work (e.g., building shelters after an earthquake or habitats underwater or on other planets). While that's likely a long way out," Werfel said, "a shorter-term application could be something like building levees out of sandbags for flood protection."
