Team of 3D-printing "Minibuilder" robots print large-scale structures on site


June 18, 2014

Working together, a team of 3D-printing "Minibuilders" can construct structures many times larger than themselves

Working together, a team of 3D-printing "Minibuilders" can construct structures many times larger than themselves

Image Gallery (11 images)

3D printers are great at creating small objects – and some can even be pressed into doing larger things, such as cars – but a 3D printer able to print a full-sized house would have to be, well, bigger than a house. To tackle this problem, a team of researchers from the Institute for Advanced Architecture of Catalonia (IAAC) in Barcelona removed the size restrictions of a printer altogether by using mobile 3D printer robots to print directly on site.

Though other structures have been printed in 3D – such as low-cost housing in China – these are produced piecemeal off site and have to be transported. This is where the IAAC concept is unique; it 3D prints structures in one continuous process, so that a building can be formed layer by layer in place.

The robots used have been dubbed "Minibuilders" because of their diminutive stature, the largest being just 16.5 in (42 cm) wide. These robots make up a team of three that all carry out different functions in the process, working independently on their own task but in coordination with each other on the overall work. Each Minibuilder performs its role in order using instructions provided by a central computer, in conjunction with its own sensors and local positioning systems. One other robot – a "Supplier" robot – provides the liquid building material to each of the Minibuilders, as required.

To create a structure, a "Foundation" robot begins by laying down the base – in the case of the exhibition structure, artificial marble – by extruding material in a precise pattern from its print head that rises as each successive layer is applied. This continues until the limit of the robots height is reached, and the next robot moves in.

The "Grip" robot follows on from the Foundation robot by attaching itself to the foundation layers using its four rollers. It then moves its way around the structure laying down further material to create the walls and using heaters to dry it. Once it has completed the walls, the Grip robot then moves on to making the ceilings and window and door lintels.

The last robot in the Minibuilder construction process is the "Vacuum" robot. It attaches itself to the surface of the structure under construction with a vacuum-operated suction cup. This robot moves up and down the construction repeatedly printing material at an almost perpendicular angle to the other layers, thereby providing strength reinforcement to the structure.

Though the first construction completed by the Minibuilders is a demonstration piece created in the exterior exhibition space of the Design Museum of Barcelona, it is envisaged that the team's work will one day lead to swarms of 3D printing robots constructing full-size structures.

The video below shows the Minibuilders in action.

Source: IAAC

About the Author
Colin Jeffrey Colin discovered technology at an early age, pulling apart clocks, radios, and the family TV. Despite his father's remonstrations that he never put anything back together, Colin went on to become an electronics engineer. Later he decided to get a degree in anthropology, and used that to do all manner of interesting things masquerading as work. Even later he took up sculpting, moved to the coast, and never learned to surf. All articles by Colin Jeffrey

Next step is to make them fly so its scalable


while this is obviously a superior approach to large scale printers, there is one major problem to be worked out.

the concrete print must solidify enough so that a printer can climb or mount the existing structure to be printed upon.

however, if the existing structure is already solidified in part, how well can the additive print that is layered on top of the existing strucuture BOND to the existing structure if it itself is a) not layered continuously and b) not at the same consistency that the existing print

if the modular approach is to succeed, the bonding of additive prints must form seamless connections, with no meaningful weakness in the lines of separation, like the seamless connections of the plates of a mature skull. observable yet containing barely any weakness at those boundaries.----


Am i the only one who saw this and saw them building this:

Joel Joines
So far concrete is not the usual material for 3D printing. And it may never be. Using newer materials seems to be the better path. Jim Sadler

Buildings are made up of more components than just concrete, for even foundations are made up of rebar, gravel and concrete; where the bed has to have a level surface to lay the foundations. Most large structures are primarily made up of a steel skeleton with concrete over steel girders; unless you have a composite material that has the tinsel strength of steel that would replace steel girders. In the video it shows the robot 3 D printer constructing a column of concrete, how much concrete would you use if this was a ten storied office building; and how would you compensate for windows?

Kristianna Thomas

Concrete (and other similar items involving Portland cement - like mortars) doesn't just "dry out". It sets or cures - because its a chemical action.

Thus it can be controlled by adjusting the formula so that sufficient strength can be achieved in time for robots to extend/climb up it.

A few years ago, back in UK, there was great excitement of fibre-glass reinforced concrete. It was exceedingly strong, in tension as well as compression, had a glass-like weather-resistant surface and could be sprayed.

Suitable adapted by more up-to-date technology like this, including colouring and texturising it may be time for a rebirth?


Mark my words This will be used robotically to build and have basic structures at the ready on the Earth's Moon and Mars

Bradley Green

Fascinating application of robotics. Definitely something to watch for in the future.

It looks like a lot of hard work and some clever thinking has gone into these machines. I am for example wondering how the suction robot manages to grip onto such a rough surface, and how it moves to the next spot - must be at least two suction cups.

Well done to the team.

Post a Comment

Login with your Gizmag account:

Related Articles
Looking for something? Search our articles