AC 2013 – Robotic Infiltrations

The project represents a continuation of research that explores the potential of additive digital production through the use of robotically controlled placement of phase-change polymers in the production of full scale structures. It is a collaboration between the University of Innsbruck’s REX|LAB and the Institute of Architecture at the University of Applied Arts Vienna.

The “ARCHITECTURE CHALLENGE” program is an international design workshop series in collaboration with international experts and institutions. It is intended for architecture students interested in exploring integrated digital design and fabrication while simultaneously designing a full-scale built project within the teaching environment of the Institute of Architecture at the University of Applied Arts in Vienna. Architectural Design at “Die Angewandte” is taught as an integrated, multidisciplinary process. Following this tradition, the design process in the workshop was enriched with robotic design strategies combining Grasshopper plugins such as the HAL and KARAMBA platforms. The workshop was taught by Andrei Gheorghe, specialists from Bollinger + Grohmann Engineers and invited guest experts Georg Grasser, Kadri Tamre and Thibault Schwartz from Technical University Innsbruck co-tutored the project. The handling of virtual simulation methods and the engineering of full-scale structures using robotic manufacturing were a primary focus of the project. Three ABB industrial robots from REX|LAB were used for on-site fabrication.

Structural Performance

Structural testing of PU foam mockups revealed a strong tension ability of the expanded material. Supporting points on the floor and suspension point on a moveable rack were defined locally taking into account the architectural site context. Possible connection lines between these points were optimized for internal bending moments using the structural plugin Karamba in combination with the genetic algorithm Galapagos.

Intrinsic Material Qualities

The geometrically accurately defined design strategy reacts with loosely defined material behavior. The precise abilities of the robots correlate with the very uncertain geometrical condition entailing from the foam expansion process. This intuitive material behavior enriches the digital precision resulting in artifacts of one – time unique aesthetic design results. Experimental and final production of the structure merge in one single fabrication process.

Fabrication Process

A Grasshopper definition was developed to extract 4-point nodes and 2-point connections from the final design network. HAL was used to compute specific tool paths for the three robots. A specific material mixture (PU foam, gypsum, water and hardener) developed at TU Innsbruck combined with precise time management was required to produce the structural nodes.

Future Application

Digital Design and Fabrication processes will have increasing importance in future architecture production. The project researches an alternative way of construction. Using industrial robots and the PU foam material in a new way, it develops ways of building full-scale architectural structures. In future, this technology can be refined to be used in fully functional small and large-scale construction.


Andrei Gheorghe, Georg Grasser, Kadri Tamre and Thibault Schwartz

External Experts on Structural Design:

Clemens Preisinger, Robert Vierlinger, Moritz Heimrath


Lu Jiaxing, Rhina Portillo, Matthias Urschler, Maria Valente, Yi Lin Vincent, Matea Ban

Many Thanks to Bollinger + Grohmann Engineers, University of Innsbruck’s REX|LAB and the Institute of Architecture at the University of Applied Arts Vienna.