Automatic for the walls


At ETH Zurich, one of Europe’s research powerhouses, high-end Swiss technology married to the power of the algorithm is producing a completely new form of automated wall construction. Strange as it may seem, the processes creators, Gramazio & Kohler, are close to squaring the circle between two apparently alien worlds; robotics and craft.

From within one of the long, large engineering buildings on the grid-crazed campus of Zurich's famous Technical University, ETH Zurich, some of the campus's most unusual research and development is emerging. There a real 'live' robot is being instructed to perforate, pattern and place materials to such precise aligned positioning that the resulting walls are transformed into things of beauty; elaborating mathematical forms and patterning to such exacting detail that they can play optical tricks on the human eye. Many materials can be used, from brick or wood, through to composites; and the patterns, whether regular or irregular can be as striking or subtle as the designer wishes.

RobotThis digital fabrication technique has already been used on various live projects in Switzerland, most strikingly for a winery near the small village of Flasch at the western edge of Graubunden by the Chur practice BearthDeplazes. Initially while being told about the winery by the bureau's partner, Daniel Ladner, with its robotically designed walls, I can recall feeling uneasy about the process with its robotics manifesto, another small yet significant step in undermining the craft process. This dissolved, however, a short while later during the visit to the winery and seeing the building amidst the grapevine-lined fields. On approaching the building a full perspectival optical illusion seemed to take hold. The assemblage of infinitesimally small calibrated bricks seemed to make the walls surface blur and almost dance as a whole, even as with each movement I made, this perspectival dance shifted. Up close, the walls began to reveal their secret. Each brick was positioned to machine level precision and taken together they created the engaging illusion, which for a moment, had left my eyes reeling. What I had needed to accept was that such precision detailing was too refined to be done by human eye and hand; a level of precision which could play tricks on the eye. Looking at and taking stock of the Flasch winery, I felt I was in the presence of a new hybrid, machine-augmented to be sure, though also within the bounds of craft, even if it was very definitely another kind of craft, another way of making.

This careful machine mediated arranging of the winery's light sandstone brick walls, also brought to mind the increasing importance and centrality given to surfaces and façade design during the last decade. In Basel, Zurich's close Gantenbein Vineyardneighbouring city, HerzogDeMeuron have partially built their enviable world reputation around what can be done with surfaces, both as far as materials are concerned, and as part of the presentational package of the HerzogDeMeuron brand of building. They aren't alone in the architectural fraternity to be doing this, of course, and buildings presentation skills, as much as the shine of any kind of surface are all of a par with our media saturated surface world. Surfaces are a sizeable part of the wow economies, and the need of cities worth their cultural salt to buy in their bit of iconic skyline. The kind of surfaces that Fabio Gramazio and Matthias Kohler, the two architects who have been pioneering the application of robotics to building processes with the ETHZ digital fabrication techniques, will most likely contribute to the transformation of the public's experience of facades and surfaces across the urban fabric and other built environments.

"There isn't anything new about this, apart from that it is computerised", remarks Gramazio while we watch the large robotic arm going through its paces in one of the ETHZ's research hangers. He may be right on this point, but the capacity to build in algorithmic instructions transforms from the ground up how automated building is conceived. Both architects are young, thirty-something, clued-up techno-academics. They have returned to their alma mater, ETHZ, and are in the third year of a professorship, the result of a competition awarded to the pair for R&D posts. They are keen to emphasise their architectural roots, and have been working as an architectural practice for the last eight years. Before that were students within ETHZ's architecture department. Both share a digital pre-history prior to ETHZ, in that they both experienced what they describe as the early nineties' 'digital/cultural revolution' big-time, as formative and defining experiences. The source of this robotics work lies in that period and its aftermath, or rather its virtual aftermath, that is what might have but didn't happen.

Gantenbein vineyard interiorBy the late nineties, with the first digital revolution largely exhausted, the pair thought that the revolution hadn't, in fact, effectively brought the physical and virtual together. Rather the opposite. The dominant focus on virtualisation had removed any common ground. This was frustrating given both were architects who, "were interested in the physicality and permanence of buildings. So we asked," says Kohler, "'how do we bring this together?' Or is it a matter, really, of one or the other? And how does programming fit in here?" Wearing their architectural hats they felt the consequences of the rapid turn to computerised architectural design had borne synthetic, blobby monsters, a computer aided design aesthetic fine as far as it went for cyberspace, but taking next to no account of the real, physical world.

Such synthetic, image and super-computer dependent complexity architecture was all the rage around the turn of the millennium, particularly in the USA. Primarily identified with Greg Lynne and his school, his fold, warp and blob inflected architectures and theorising was wholly the result of the arrival of computer power on the architecture scene. Not completely surprisingly, though perhaps a tad ironically given the pairs' critique, Gramazio was an assistant to Lynne while the latter was professor at ETHZ. He worked on surface prediction design and describes the period with Lynne as inspirational. There's a direct influence from and reaction to that whole period, Lynne included, in Gramazio and Kohler's approach.

facade from insideThe pair readily acknowledge they operate within these influences, but what they are interested in, both repeatedly say, is the actual physical endpoint, the built structures rather than the virtual phantasies. "Our work shows us," they say, "that our final goal needs to be physical and not imaginary." Kohler divides their approach into a three-fold programme: the combination of programming and construction; drawing the conceptual stage into the physical realisation; and ensuring that each design step is directly connected to the actual building steps. In effect, no division between theory and practice. A specific additional consequence regards complexity: "We are not trying to depict complexity, rather what we're doing is towards simplicity," says Gramazio.

The process of applying computer programming to robotics is a form of digital fabrication, described by Kohler as additive fabrication, computer controlled surface 'creation.' This contrasts with the overwhelming norm in architecture, with both discipline and practice dominated by subtractive technologies; the removal of excess material. "We began thinking about adding material, to re-integrate additive procedures into building. This led to asking what were the most sensible ways to proceed with additive processes. Early on we began by exploring concrete surface patterns through using CNC milling technology." Kohler notes the distinction between milling and robots, both are machines controlled by data, but a robot contains anthropomorphic characteristics and in the case of the ETZH robot, upper limbs or arms: "It's definitely a step on from CNC milling."

facade from outsideGramazio points to the questions that such digital surface patterning raises. "How do you deal with corners, when there is patterning on every dimensional face and can these patterns be made continuous – though broken at the edges? How are these issues resolved?" Through a relatively thorough approach to considering the preconditions that constitute valid research, it is these sorts of questions which they describe as "interesting and valid forms of research." "It's generic, low cost, available and reliable," says Kohler falling into programming jargon for a moment, "so if there's a plus value that is more than a cost value, why not?" The pair also stress that practical ends, real functionality to façades, forms the programming work; from acoustics through to thermal patterning. "It's not about surface patterning or decoration as such, in a way it's a critique of ornamentation." By way of example they point to an early demonstration for Switzerland's 2002 Millennium Expo, where the sWISH pavilion was roofed in an especially perforated panelled ceiling, with the perforation drilling time costing less than painting the ceiling would have done.

The pair believe their architectural background is significant. "This wouldn't have come from engineers as they don't research so deeply," claims Kohler, pointing to how architects have been much more responsive to the possibilities of the process, wanting to experiment with the technology in ways that engineers do not. They are terming the robotics-skills interface that they have arrived at, Digital Materiality, and say there is a growing network exploring versions of this hybrid. In their recent Digital Materiality in Architecture, the pair argue that digital fabrication is enabling architects to no longer begin by designing the form, but through digital fabrication, designing the production process itself. If there is a strong architectural slant to the work, it is hard not to see their work as very much part of Switzerland's long tradition of high-end technical expertise, and it is not surprising when they agree to the suggestion that it is unlikely these techniques would have arisen anywhere else but ETH Zurich, one of Europe's technical and technological research powerhouses.

constructionThe physical application of digital fabrication at the Flasch winery is also down to serendipity within the ETHZ's architecture department. The two young techno-wizz's took up their posts at same time as Andrea Deplazes was just beginning as its new dean. Much of the winery was already built when Deplazes was first introduced to the techniques, but with the support of Christian Keller, head of Keller Bricks manufacturer the KR 150 L110 robot set to work putting each brick in place finishing complete wall units which were then transported to the Flasch site to be installed. "One of the good things about Andrea is that he is absolutely not interested in computers. He wasn't aware of nor did he have any ideas about the digital revolution."

Since the winery the pair have worked again with BearthDeplazes on a Zurich tram stop shelter, although this ran into the funding buffers and so was never realised. With the support of Keller, who worked on an earlier pre-computer generation of automated building research, Gramazio and Kohler are working on a number of other projects, including one where the robotic arm can be transported to, and work on, sites. This introduces additional flexibility into what is currently only a nascent wing of construction. Where this will go is somewhat open-ended at present, even if the endgame they agree, perhaps alarmingly, is automated (including virtual and remotely operated) house and other building type construction.

The pair are also finishing the façade for a private house in Zurich, working on the sun protecting louvers, looking at the distribution and angles of the light rays. It is in a project such as this where both the functionality and something of a sustainability dimension come into play: how to develop louvers which work most effectively with lighting whilst complemented with a striking façade. Gramazio says the sustainability question hasn't really impacted when I ask about any embodied energy studies of using robots, although he notes his belief that such robotic programming could reduce both materials and waste usage and may become significant in the sustainability debate within the materials and construction sector.

Gantenbein VineyardThe louver façade is planned to be in wood, and Gramazio and Kohler have often applied the robot arm to timber test projects at ETHZ, such as Sequential Wall 2008, as well as to various other materials, including concrete blocks and foam. I have foregrounded the craft element to what is happening here, highlighting how wood - immediately identified with skill and the craft of carpentry – is a part of digital materiality's repertoire. It's use with mass-produced bricks, with brick-laying, and with the palette of other materials that do not fall so easily into the perceived sphere of craft work partially redefine these materials. Materiality brings new life, opening people's eyes to qualities often missed in materials, as is the case with the humble bricks at the winery. Indeed digital fabrication's widespread application across the material spectrum gives the technology a patina of neutrality: as either dumb or smarter technology there is no reason that it could not be applied equally to a lo-tech building material tradition as much as to a hi-tech one. Such a spectrum of uses might well suggest that the oft-made immediate assumption that hi-tech (including robotics) leads to hi-tech futures isn't actually completely inevitable.

Likewise, if this hi-tech version of construction may be a bit scary for craft purists, believing in the purity of the human-made building, the winery stands quietly reassuring, acting as something of a counter-gesture to such pessimism. The building follows the form and volumes, as precisely as it can, of the initial vernacular barn which the Gantenbein family built themselves. Robots for ruralism? Perhaps. Of course, the building is a showpiece, partially designed to bring folk like myself to look admiringly at it and its strangely appealing optical device. And yes, one can easily imagine a world gone awry where the process has been 'handed over' to the robots. But the Gantenbein winery doesn't speak sci-fi, rather suggesting something else closer to using such twenty-first century technology in balance with the past. It is a very different pathway, part of the evolving crafts and computers conversation, perhaps a new beginning in that it reverses the usual maxim that computers augment the maker. Here the robot may be in control, and the making is in its hands, but this time it has led to sensuality and an enrichment of craft rather than its impoverishment.


Digital Materiality in Architecture is published by Lars Müller Publishing