In Situ's construction robot can automate on-site building
The In Situ Fabricator1 is a construction robot able to build structures with a precision of less than 5mm and operate semi-autonomously in complex environments. Developed by Markus Giftthaler at ETH Zurich, a Swiss university, the robot uses a flexible robotic arm to position construction tools and connects to the internet, enabling real-time changes to be made to plans. Equipped with cameras to sense its environment and powerful on-board processors for navigating and planning tasks, the robot will be used to build structures on an experimental construction site in Switzerland.

That’s a big ask, but the potential benefits are huge. Construction robots would allow new types of complex structures to be assembled in situ rather than in distant factories and then transported to the site. That allows new types of structures to be built in place, indeed these structures could be modified in real time to allow for any unexpected changes in the environment.

So what is the state-of-the-art for construction robots?

Today we get an answer thanks to the work of Markus Giftthaler at the ETH Zurich in Switzerland and a few pals who have developed a new class of robot capable of creating novel structures on a construction site. They call their new robot the In Situ Fabricator1 and today show what it is capable of.

The In Situ Fabricator1 is designed from the bottom up to be practical. It can build stuff using a range of tools with a precision of less than five millimeters, it is designed to operate semi-autonomously in a complex changing environment, it can reach the height of a standard wall, and it can fit through ordinary doorways. And it is dust- and waterproof, runs off standard electricity, and has battery backup. On top of all this, it must be Internet-connected so that an architect can make real-time changes to any plans if necessary.

Those are a tricky set of targets but ones that the In Situ Fabricator1 largely meets. It has a set of cameras to sense its environment and powerful onboard processors for navigating and planning tasks. It also has a flexible, powerful robotic arm to position construction tools.

To show off its capabilities, Giftthaler and co have used it to build a pair of structures in an experimental construction site in Switzerland called NEST (Next Evolution is Sustainable building Technologies). The first is a double-leaf undulating brick wall that is 6.5 meters long and two meters high and made of 1,600 bricks.

Even positioning such a wall correctly on a construction site is a tricky task. In Situ Fabricator1 does this by comparing the map of the construction site it has gathered from its sensors with the architect’s plans. But even then, it must have the flexibility to allow for unforeseen problems such as uneven terrain or material sagging that changes a structure’s shape.

“To fully exploit the design-related potentials of using such a robot for fabrication, it is essential to make use not only of the manipulation skills of this robot, but to also use the possibility to feed back its sensing data into the design environment,” say Giftthaler and co.