Harvard University engineers have used termites as inspiration for a new breed of robot. These small robots are able to build complicated structures without a centralized plan by following simple rules of organization. Using a process called stigmergy, which is when individual parts of a system interact with one another indirectly by modifying their surrounding environments, the robots build structures. They have sensors that enable them to perceive other robots and bricks surrounding them which then help the robots determine which programmed movements to use. The engineers explain that the robots are also easy to program as they only have four sensors – ultrasound, infrared, tactile sensing and an accelerometer that is used to climb. These sensors help the robots adhere to preprogrammed traffic rules. While they have no knowledge of the state of the overall structure, they know not to build themselves into traps they cannot get out of.
The work was unveiled at a meeting for the American Association for the Advancement of Science on Thursday. The robots demonstrated their capabilities by building a structure with plastic bricks that followed a predetermined pattern. Justin Werfel, author of the study, said that tiny termites in nature inspired the team to learn their techniques of how they work together and build complicated structures. Termites have long since been renowned for their building of complicated structures and while they have developed a reputation for being pests, they have proved to be composed of completely sufficient, organizational networks. Much like hymenoptera insects, such as bees and ants, termites delegate tasks throughout their colony which can contain anywhere from a few hundred to a few hundred million. Using swarm intelligence, termites operate in a decentralized and self-organized team that can build mound structures up to 29 feet in height and contain tunnel structures up to 360 feet long.
The Harvard team drew inspiration from the tactics of termites and their systematic building techniques when creating computer programs for the robots. It is through the combination of several simple movements from each robot that the structures are made. The robots by themselves are not complicated in their process; it is in the way they coordinate their movements with other robots that make them able to build complicated predefined structures. The robots know when and how to pick up a brick, turn and climb a stair. These are basic functions but their teamwork as unit has been described as quasi-intelligent. Werfel explains how the robots as a team can also accommodate to change saying “there is no one critical element that can bring everything down if one fails.” That means that the robots can adapt to having new robots added to their building teams without any reprogramming needed, even if its while they are working. Also, if the structure’s size demands for more robots, then more robots can simply be added without disrupting the workflow.
The robots may be prototypes for future robots that can build complicated structures in areas humans can not go to. The team talks of how they can be ideal for space as they can adapt to changes and if one breaks, the building mission can continue uninterrupted. Even on earth, the robots may be able to work in dangerous earthquakes where it is unsafe for humans. If these small termite-inspired robots are someday used to build structures in space, the work of the Harvard engineers is a giant step toward new frontiers for humans.
By Lian Morrison
The Journal of Insect Science