Rescue robots demonstrate swarm-like intelligence

Self-organising robots that mimic the swarm-like intelligence of termite colonies have been demonstrated by a team of Harvard University engineers.

The TERMES robots can build towers, castles and pyramids out of foam bricks — erecting staircases that let them reach the higher levels and adding bricks wherever they are needed — using only four simple types of sensors and three actuators. In the future, the researchers say similar robots could lay sandbags in advance of a flood or even perform simple construction tasks on Mars. "The key inspiration we took from termites is the idea that you can do something really complicated as a group, without a supervisor, and, secondly, that you can do it without everybody discussing explicitly what's going on, but just by modifying the environment," said principal investigator Radhika Nagpal. In a similar way to how termites use stigmergy — a kind of implicit communication — each TERMES robot is designed to execute its building process in parallel with the other robots, but without knowing what else is working at the same time. If one robot breaks, or has to leave, it does not affect the others. This also means that the same instructions can be executed by five robots or 500. Whereas other systems rely on an 'eye in the sky' approach, in which a central controller is used to make sure all of robots are communicating properly, as the number of robots and the size of their territory increase, these systems become harder to operate. Furthermore, in dangerous or remote environments, a central controller presents a single failure point that could bring down the whole system. "It may be that in the end you want something in between the centralised and the decentralised system. But we've proven the extreme end of the scale: that it could be just like the termites," said Nagpal. "And from the termites' point of view, it's working out great." Check out the video below to see the robots in action.