Zurich/Zug – The limits of interactive architecture design and digital fabrication are now being pushed at the Swiss Federal Institute of Technology Zurich (ETH): four robotic arms are using artificial intelligence to build a 22.5-meter-high planted sculpture called Semiramis at the Tech Cluster Zug.

The Tech Cluster Zug will gain a hanging garden based on the ancient model. The envisaged planted architectural sculpture for this is called Semiramis. It is 22.5 meters high and consists of five geometrically complex wooden pods of different sizes that are placed one on top of the other. A video presented in a press release from the ETH shows how these will be supported by eight thin steel pillars.

Researchers from a group led by ETH architecture professors Fabio Gramazio and Matthias Kohler are designing and creating Semiramis together with the landscape architecture firm Müller Illien Landschaftsarchitekten, wooden structure engineers from Timbatec, and additional partners from industry and research. The design options come from a machine learning algorithm that was developed in collaboration with the Swiss Data Science Center.

Matthias Kohler, Professor of Architecture and Digital Fabrication at ETH Zurich, explains: “The computer model lets us reverse the conventional design process and explore the full design scope for a project.” The researchers were able to explore the drafts in three dimensions at the Immersive Design Lab, an ETH augmented reality lab. Software developed together with the Computational Robotics Lab at the ETH enabled modifications to the drafts. This beacon project for architectural research is “advancing the key research topics of the present, such as interactive architectural design and digital fabrication,” according to Kohler.

The Semiramis sculpture is currently being built by four robotic arms working together at the Robotic Fabrication Laboratory at ETH Zurich. An algorithm prevents collisions when they simultaneously lift one of the wood panels and position it. The robots are relieving humans of the tasks of heavy lifting and exact positioning. They also eliminate the need for costly scaffold construction.

Each of the individual pod segments consists of 51 to 88 wood panels. When one is ready, it is transported to Zug by truck. Semiramis is to be erected and planted out in spring 2022.