Even though most buildings are designed using the latest digital tools, actual construction is stuck in the past; building is messy, slow, and inefficient. 3-D printing might change that, but recent projects like these printed houses in China demonstrate one of the technical challenges–the equipment itself has to be gigantic, because it can’t work unless it’s bigger than the building itself.

A team of researchers from Institute for Advanced Architecture of Catalonia are working on another solution: A swarm of tiny robots that could cover the construction site of the future, quickly and cheaply building greener buildings of any size.

The robots work in teams to squirt out material that hardens into the shell of the building. Foundation robots move in a track, building up the first 20 layers of the structure, and then a series of “grip” robots clamp on the top or sides adding more layers, ceilings, and frames for windows or doors. Vacuum robots attach on at the end to add a layer to reinforce everything.

Other 3-D-printed architecture requires frames, which have to fit entirely around a building, or robotic arms that can only reach as high as themselves. “If you want to make an object as big as a stadium or a skyscraper you’ll need to design a machine bigger than that object in at least one axis,” explain researchers Petr Novikov and Sasa Jokic. “Making such machines isn’t economically reasonable, sustainable, and, in some cases, simply impossible due to their size.”

The Minibuilders could in theory build anything. “The robots can work simultaneously while performing different tasks, and having a fixed size they can create objects of virtually any scale, as far as material properties permit,” say Novikov and Jokic. “They are extremely easy to transport to the site. All these features make them incredibly efficient and reduce environmental footprint of construction.”





Because the technology wouldn’t require custom molds or even support structures, there would be zero construction waste. It could also save materials by printing a little extra only in places where the building needs more support.

Eventually, the designers see the robots being used to take care of pretty much every conceivable construction task. “They are an ecology of small construction robots, and this ecology can be extended far beyond 3-D printing,” the researchers say. “In the future, we envision robots that do also painting, piping, and variety of other tasks.”