Using soil or sand and some solar power, this little robot can 3-D print the walls for a single-story house or even a bridge in the middle of the desert.
“We wanted to use robotics to solve problems that can’t be solved by traditional construction methods,” says Petr Novikov, who built the printer along with Inder Shergill and Anna Kulik as a thesis project in 2012 at the Institute for Advanced Architecture of Catalonia.
They decided to tackle the challenge of building in drylands and desert areas, where construction materials are limited and labor is especially difficult because of the heat. The design uses local materials, prints everything on site so there’s no transportation involved, creates no waste, and is low-cost.
It’s somewhat similar to Markus Kayser’s Solar Sinter, which also prints using sand. But this robot can use soil as well, making it more versatile, and it’s also much smaller, so it’s easier to move around.
Soil or sand is mixed with a binder to help it hold together, and then the robot sprays the mix into an organic-looking form. Unlike standard 3-D printers, it can print horizontally as well as vertically–making it possible to print, for example, a bridge between two rocks.
“If you look at common 3-D printers now, they all work in different ways, but use the same principle–building up a model in horizontal sections,” says Novikov. “This is of course an ingenious method but it brings lots of problems with support material. Once you want to print hanging structures, you have a problem. We can print on any type of surface–vertical, horizontal, rough, smooth.”
The process works best in dry, sunny climates, both because it can run on solar power and because sunlight helps speed up the process of setting the material. Since it takes a couple of days for the soil mixture to fully set into a solid form, rain is a problem. “After it cures it can get as wet as you want,” Novikov explains. “But you cannot print while it’s raining. It’s meant for drylands.”
During their research, the architects tested building a small wall along with some furniture. “For one story buildings and walls, this technique works well,” Novikov says. Since the idea was created for a thesis, it hasn’t been developed further, though Novikov says some of the principles behind it have inspired his subsequent work.
“I’m still working in the field,” he says. “While I won’t necessarily continue with this particular project, I’ll definitely go back to the idea of using ecological materials.”