New possibilities through collaboration

Working with industry and university partners, SOM is developing new techniques and applications for construction aided by robots. “Anatomy of Structure: The Future of Art and Architecture,” at Ambika P3 Gallery in London, presented several results of this collaboration. The show’s dramatic centerpiece is a vault structure, built of glass bricks, that was assembled by robots in the gallery throughout the course of the exhibition.

Structural engineers at SOM developed the installation in collaboration with Princeton University CREATE Lab and Form Finding Lab, with assistance from the TU Delft Glass & Transparency Research Group. The robotic arms were provided by Global Robots and the glass bricks were provided by Poesia Glass Studio. Combining its expertise, the team developed a material system, structural design, and assembly strategy to enable robotic arms to assemble a self-supporting vault. The research behind this installation draws upon traditional vault construction methods while applying advanced engineering techniques to create an efficient and beautiful shell structure that can be built entirely without formwork or guides.

Bringing an ancient building method into the 21st century

The doubly curved vault concept has a solid foundation in structural theory. The structure created for exhibition is a type of timbrel vault, a masonry construction method first developed in the 14th century. Older structural vaults are found throughout the Mediterranean, and early  modern architects and engineers including Gaudí and Guastavino made the technique known all over the world. The installation at Ambika Gallery revisits this construction technique, harnessing robotic capabilities to fabricate an aesthetically striking structural design.

The inspiration to build a glass-brick vault came from SOM’s ongoing collaboration with the Taller de Bóvedas Tabicadas (Timbrel Vault Workshop) at the University of Alcalá in Madrid, where teams of professors and students have been developing and building ultra-light, yet efficient and strong timbrel vault structures. The annual workshop seeks to revive this affordable, centuries-old construction method, which has particular value in places where resources are scarce. 

The construction sequence for the glass vault was also inspired by an ancient barrel vault technique that allowed for construction without formwork, relying on inclined courses set against a vertical end wall. For the robotic construction, layers of arches are built off a central arch, and the bricks are staggered on either side for stability.

Demonstrating the concept

The vault installation at Ambika Gallery shows how robotic fabrication methods can produce new and more efficient ways of building. The two robotic arms work in tandem: one serves as a temporary support while the other places the material. The accuracy and spatial awareness of the robotic arms allow them to place the glass bricks without the need for guides or formwork.

This robotic technique does not eliminate the need for human insight—in fact, the glass vault construction depends on close collaboration between robots and humans. The robots perform tasks that require precision and accuracy, while humans make real-time adjustments, such as applying the epoxy to gap sizes that vary due to geometry. As opposed to traditional construction methods for arches, which normally build from both supports upwards, the robots alternate placement and support to construct the arch from one end to the other without any scaffolding.

Building with glass

Glass is seldom employed as a structural material, even though its high compressive strength is a desirable property for vault structures. The team chose glass bricks to showcase the structural and aesthetic potential of this easily recyclable material. The bricks are laid in a herringbone pattern, which is inherently stable due to the interlocking mechanism it creates between the bricks.

The team studied various materials for the connection between the glass bricks: it needed to be fast-setting and rigid, with enough tensile capacity to hold each brick in place during construction. The material also needed to negotiate variations in the gap sizes between the bricks due to geometry, as well as material and construction tolerances. Ultimately, the team selected a fast-setting epoxy putty as the connection material. 

Since glass has high compressive strength and low tensile strength, the geometry of the vault had to minimize any tensile forces. Digital modeling helped the design team determine the most efficient shape of the vault structure, which enabled the identification of a doubly-curved, compression-only shell.

The vault shape was also conceived to showcase robotic capabilities: in particular, spatial awareness and the potential for collaborative interaction. The shape was determined by the limit of reach of the robots’ arms, and the clearance required for their movement. Finally, the team planned the construction sequence to ensure the stability of the structure at every step.

Future possibilities

The glass vault installation allows us to imagine a range of possibilities that combine robotic capabilities with human ingenuity. In the realm of disaster response, the speed at which structures could be built with the aid of robotics opens up potential applications for rapidly constructed emergency shelters. In places where resources are scarce, a return to traditional building methods could offer a solution for durable, low-cost construction. Robots could even be deployed to construct similar structures in harsh environments, whether on the Earth, the Moon or Mars. And these methods provide efficient alternatives for more typical construction projects, where the benefits in how we use materials could be significant when applied at scale.