Swarming metamaterial robots could build bridges and other large structures

Rich McEachran

Mechanical metamaterials developed at MIT (Credit: MIT)
Mechanical metamaterials developed at MIT (Credit: MIT)

You’ve probably heard about army ants working collectively to build bridges with their bodies, but what about an army of swarming robots assembling structures with modular materials?

It may sound dystopian and straight from the pages of a science-fiction novel, but this is exactly what could be possible in the future, according to research carried out by scientists at Massachusetts Institute of Technology’s Centre for Bits and Atoms, in conjunction with the US Army. 

In a paper published in Science Advances, the research team demonstrated how they can link together metamaterials with certain mechanical properties. Akin to a set of Lego pieces, this building block-style approach to design results in modular materials that can be reconfigured for different uses. The team demonstrated how they were able to build a 5m bridge that can withstand several hundred kilograms. The metamaterials were also reconfigured into a temporary shelter.

As Dr Christopher Cameron, an aerospace engineer at the US Army Research Laboratory, who was instrumental in the research, hypothesised: “If a swarm of robots can turn themselves into a bridge, how else can they be arranged? How do we design and control robots like this?”

Into battle

The answer to the second question is still being explored. As for the first question, the team expects that the technology in its current state could be deployed on the front line, where tough terrain and harsh conditions mean it can be hard to transport the required materials and tools to build a makeshift bridge, for example. 

Further afield, though, and this type of modular, robot swarm system could be used to build a variety of other structures and even equipment. Perhaps small wind-turbine blades or ladders and such like required by engineers to carry out maintenance or surveying work. 

On the basis of the MIT and US Army research, a turbine blade made from interlocking metamaterials would be more efficient. This is because they could be designed to have desired mechanical properties, which, in theory, means a blade could respond dynamically to the strength of the wind. 

Typically, structures such as bridges are monolithic. The manufacturing involves a lot of input and resources to create materials that are rigid and limited in their capability. Having modular components with mechanical properties, however, means that materials can be repurposed. Not only this, but there’s less waste and costs are lower. Different large, functional structures can be created from many mass-produced, smaller parts. Manufacturers no longer have to be as concerned about their waste stream and what they need to do with scrap material.

Open the box

It could also eradicate the problem of what to do when a structure reaches the end of its lifecycle. Wind turbines are extremely difficult to recycle and disposing of them can be cumbersome.

The most likely scenario is that a box of swarming robots will be used in remote, hard-to-reach locations, emergency situations, or when a rapid response is required. Their lightweight nature means these Lego-like building blocks are easy to transport. A box of swarming robots could be taken to a site, opened, and the robots would quickly assemble the metamaterials into the required structure. Once the built structure is no longer needed, the metamaterials can be packed away and the box taken to the next location. 

Want the best engineering stories delivered straight to your inbox? The Professional Engineering newsletter gives you vital updates on the most cutting-edge engineering and exciting new job opportunities. To sign up, click here.

Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.


Read more related articles

Professional Engineering magazine

Professional Engineering app

  • Industry features and content
  • Engineering and Institution news
  • News and features exclusive to app users

Download our Professional Engineering app

Professional Engineering newsletter

A weekly round-up of the most popular and topical stories featured on our website, so you won't miss anything

Subscribe to Professional Engineering newsletter

Opt into your industry sector newsletter

Related articles