Termite Inspired Robots Build Complex Structures

Drawing inspiration from termites, a team of scientists has developed an autonomous robotic construction crew 'TERMES' that functions without communication and supervision.

Researchers at the Harvard School of Engineering and Applied Sciences (SEAS) and the Wyss Institute for Biologically Inspired Engineering at Harvard University have created robots that complete construction tasks just like termites. The four-year project TERMES, mimicked termites swarm intelligence and construction system in which small autonomous robots build foam 3D structures. They work without the need for any central command.

Millions of termites gather together to construct a mound of soil. These insects follow each other and don't indulge in any complicated planning. They also lack a sense of overall plan. They instead use cues from the environment to complete the construction. It is this resilience and collective intelligence of these insects that struck the researchers.

The 180cm- long TERMES robots can build towers, castles and pyramids using foam bricks. They can also build staircases to reach greater heights and add bricks in open spots using sensors. BBC reports that the bots have four simple types of sensors - infrared, ultrasound, accelerometer for climbing and tactile sensing for push.

"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," principal investigator Radhika Nagpal, Fred Kavli Professor of Computer Science at Harvard SEAS, said in a statement.

Unlike a human construction project, which is based on blue prints and requires long discussions and planning, termites work on stigmergy-an implicit communication system. The termites work identifying changes in the environment. TERMES robots are designed to function in a similar manner.

"They have some traffic rules that tell them how to move through the work space, and these correspond to the particular type of structure being built. That is, if you ask them to build something else, the traffic rules will be different. And they also have some safety checks that ensure they never put bricks that back them into a corner, such as building a cliff they can't then climb over," lead author Dr Justin Werfel from the Wyss Institute for Biologically Inspired Engineering at Harvard University, said to BBC News.

Every single robot completes the building process along with others. One robot's performance does not affect the others.

"We co-designed robots and bricks in an effort to make the system as minimalist and reliable as possible," says Coauthor Kirstin Petersen, a graduate student at Harvard SEAS with a fellowship from the Wyss Institute. "Not only does this help to make the system more robust; it also greatly simplifies the amount of computing required of the onboard processor. The idea is not just to reduce the number of small-scale errors, but more so to detect and correct them before they propagate into errors that can be fatal to the entire system."

According to the researchers, similar robots could be used to lay sandbags before being hit by floods. The TERMES could also help carry out construction tasks on the Red Planet.

The finding was published in the journal Science.