Film still by schwarzpictures.com

Meet Maria Vittoria and Inés!

To celebrate Women’s Day 2021 and the 50th anniversary of women’s right to vote in Switzerland, the Swiss NCCRs (National Centres of Competence in Research) wanted to show you who our women researchers are and what a day in their job looks like. The videos are targeted at women and girls of school and undergraduate age to show what day to day life as a scientist is like and make it more accessible. Each NCCR hosted a week where they published several videos covering multiple scientific disciplines, and here we are bringing you what was produced by NCCR Digital Fabrication.

The videos cover a wide range of subjects, including (but not limited to) maths, physics, microbiology, psychology and planetary science, but here we have two women who work with robots.

Maria Vittoria Minniti is a robotics engineer and PhD student, she enhances mobile manipulation capabilities in under-actuated robots.

Inés Ariza is an architect, she uses a robot to 3D print custom metal joints for complex structures.

Head over to YouTube or Instagram (English, German or French) to see the women featured in the #NCCRWomen campaign.

In-situ fabricator. Source: NCCR Digital Fabrication

Digital fabrication enables the seamless combination of digital design with physical construction processes. To fully exploit this emerging technology within architecture, robotic fabrication must be expanded in prefabrication, but also fully implemented directly on construction sites. Achieving in-situ fabrication using mobile construction robotics is the goal of several research projects within the National Centre for Competence in Research (NCCR) Digital Fabrication.

In order to be able to work on a construction site a robot must be:

• mobile
• robust
• precise
• aware of its position on the construction site
• and able to adapt to uncertainties

These issues have already been subject of previous research including a recently completed doctoral thesis by Volker Helm. This initial project executed at the Chair of Architecture and Digital Fabrication resulted in the “dimRob” platform; an industrial robot arm mounted on a mobile track system and powered by a diesel engine. The robot was able to move across different terrains, manipulate materials and tools for construction, and was also fitted with a scanning system to manage the construction tolerances. The functioning of “dimRob,” however, still required significant human interaction: The robot had to be driven, stabilized, and localized manually by an operator before being able to build.

A new interdisciplinary collaboration will take this robotic platform to the next level, with the long-term goal of transforming the platform into an autonomous robot – the “In-situ Fabricator.” This augmented system will reduce the need for manual input and should be able to accurately build complex structures to millimetre level construction tolerances, while simultaneously being able to deal with the uncertainties of a construction site.

Timothy Sandy, PhD student at the Agile & Dexterous Robotics Lab (ADRL), ETH Zurich, explains that “the system should rely solely on on-board sensing and computing.” This is the crucial distinction compared to its precursor and a significant developmental challenge. Together with his colleagues Markus Giftthaler, PhD student at ADRL, and Kathrin Dörfler, PhD student at the Chair of Architecture and Digital Fabrication, Sandy is part of the interdisciplinary project team formed within the NCCR Digital Fabrication. This research initiative, funded by the Swiss National Science Foundation (SNSF), enables interdisciplinary collaborations and projects that individual disciplines are unable to achieve alone.

The robot’s arm is equipped with a laser range finder. As the robot sweeps its arm, the laser measures points in space to generate a 3D map of its surroundings. This map is registered against an initial scan of the context in order to calculate the robot’s position. Source NCCR Digital Fabrication

“One of the big challenges in the past month was the development of a precise localisation system”, Kathrin Dörfler explains. This might sound trivial, but how can a mobile robot localize itself when it doesn’t have an external reference point on which to base its coordinate system? A first proof of concept of the localization system was demonstrated in March. The method uses a 2D sweeping laser rangefinder that scans the surroundings to generate a 3D map of its context. This map is then registered against previous scans of the space in order to calculate the robot’s position.

A similar scanning and measuring feedback loop is also used to cope with the tolerances of construction: by comparing the point cloud scans of the existing state of construction to the CAD model of the structure to be built, the robot and its control systems are able to determine any small deviations from design and make adaptions within the construction process. “One of the shortcomings of previous robotic fabrication technologies, is that they are not linked to the design environments of architects,” says Dörfler, explaining the value of this technology to her profession. By linking the CAD systems used by architects with the technologies that build, there is a stronger understanding of what is possible and how to use the technology creatively.

Patches of bricks for assembly are automatically generated according to the robot’s location and range constraints. Source: NCCR Digital Fabrication

All of this sounds as if the “In-situ Fabricator” is ready to go on site tomorrow. However, according to the researchers, the technologies and processes are still “primitive” for now. Sandy explains: “At the moment the robot can be considered to be ‘working in the blind.’” This means that, after having moved, it isn’t aware of its position anymore, and first has to localize itself again. “In future the robot should be continuously aware of its position, even when in motion, and capable of steady, and accurate construction.” Only then will the seamless combination of the digital design with the physical construction process be entirely achieved.

Professor Robert J. Flatt. Source: DFAB

Being able to control the moment when concrete turns from liquid to solid is crucial for digitally fabricated concrete structures. The timing of this process can be controlled by tuning the chemistry and adding small amounts of specific substances at just the right time. Robert J. Flatt, Professor of Building Materials at ETH Zurich, discusses this process and the innovations in concrete chemistry and digital fabrication he and his team are working on to reduce the environmental footprint of the most used building material in the world.

“Test the limits and break through (…) no rules for me (…) let it go!”, you used this song from the Disney film “Frozen” in a presentation on your research. How are you working to get rid of rules?
I’d rather say: We try to do things that, at first, seem unfeasible. Lets take the making of a cake as an analogy. In general you have dough, which is fluid. You pour it into a mould and then put it into the oven to harden. What we are working on is similar to a process that would extrude this dough and have it immediately shaped and cooked. You could say: We are trying to remove steps of common processes by forcing the material to behave differently.

“The key is to use the critical moment when the material transforms from liquid to solid.” What does this mean in practice?
We are working on what I call the “spices” of concrete. Added to a mixture in very small amounts, these additives have a huge impact on the material properties. I give you an example. The research project “Smart Dynamic Casting” (SDC), a collaboration with the ETH Chair of Architecture and Digital Fabrication, started with the question: Can you make complex shapes of concrete without any formwork? SDC is an answer to this challenge, in which the key is to be able to use the critical moment when the material transforms from liquid to solid; when you can shape the material, but it doesn’t collapse under its own weight.

SDC also has been your first collaboration in the field of digital fabrication, before joining the National Centre of Competence in Research (NCCR) Digital Fabrication. Where are the synergies between material sciences and digital fabrication?
Digital fabrication in concrete wouldn’t work without the manipulation of the material properties. You either would end up with a very inefficient process or the process would simply fail. On the other hand, robotic control opens new perspectives to surpass current state-of-the-art construction processes, particularly for more individualized structures. For me this interdependency of material design and robotic processes is the exciting part about this research field, and bringing our expertise to this collaboration is where we see our role within the NCCR Digital Fabrication.

“A big opportunity is to combine the manipulation of the material properties with the reduction of the environmental footprint.” What is the added value of these new fabrication processes and materials compared to traditional ways of building?
If you take SDC, the overall interest was to be more efficient in producing complex shapes. So the added value is about creativity and efficiency. Furthermore, by replacing traditional formwork with a single adjustable slip-form, waste can be reduced. However, in terms of the overall environmental impact I consider the elimination of the formwork to be of second order. A much bigger opportunity is to combine the manipulation of the material properties with the reduction of the environmental footprint of concrete. Accordingly, the development of more environmentally friendly types of concrete is one of our main research focuses and also one of our major long-term goals, of which we plan to feed the results into the NCCR Digital Fabrication.

5 to 8% of the man made CO2 emissions is effected by cement production. Why do you focus on concrete and not on a building material with less environmental impact?
Concrete is the most used building material in the world. It is used in larger quantities than all the other building materials added together [1]. There are basically no other materials available in the quantity that can compete with concrete in terms of performance, environmental impact and cost. This huge volume of concrete also means that: If you simply succeed in reducing the amount of cement used in concrete you have a huge multiplication factor. As an example: about 40% of Switzerland’s Kyoto Protocol objectives where reached by the cement industry. Part of this reduction is due to the fact, that less concrete was used, part of it due to improvements in production, and part due to changes in the nature of the cement being produced. That brings us back to the “spices”; these additives can be used to tune the material properties, but you also can use them to keep required values of some properties while changing the proportions of the materials you used. As an example; chocolate producers are now allowed to replace 5% of the cacao fat with vegetable oil, but of course they don’t want to change the taste. In our research we try to do the same, but our goal is not to replace 5%, but 50% of the material. To accomplish this we need to formulate very good spices for it to go unnoticed!

In your experience, what factors are required for a research innovation so that industry will take interest?
An innovation, of course, needs a market perspective. In this sense environmental aspects are certainly a macro trend that impacts their long-term strategic considerations, however it is clearly the costs of materials, energy, and the impact of CO2 emissions that will influence marketability in the long term. The balances between impact issues and how to bring an innovation to market are definitively the high-level strategic considerations for industry.

So, if the NCCR Digital Fabrication wants to be successful, in practice it should focus on environmental issues?
This conclusion is too limited and brief, whereas the goals of the NCCR Digital Fabrication are long-term. I would rather describe the process as such: In the first phase we are more in the logic of developing something like a Formula One car, a niche product. So, of course we are concerned with doing things in a sustainable way, but we are still addressing a small portion of the market. We are looking at opportunities with high added value, rather than large volumes where processes are much more optimized and margins are very tight. At this stage looking at the large volume market from the perspective of digital fabrication could be a killer for innovation. Then, in a later stage, we intend to evaluate which part of our innovations can be adapted to larger scale use. This is where we can optimally shift our attentions to larger issues such as sustainability. Once we have resolved the smaller scale problems we can shift to volumes that allow us to have a large-scale ambition and a large-scale impact to improve sustainability.

Are there any risks you can think of regarding the path on which this NCCR is heading?
If you want to build a Formula One car and you can build it more efficiently with a robot that has special features, you might well be persuaded to also use this very versatile robot for normal serial production, but this may not be the most optimal solution. The big question for me is: Will our increased use of digital fabrication eventually lead to automation with a loss of design individualization? This is, of course, exactly the opposite of what we are aiming to accomplish within the NCCR Digital Fabrication. So, to answer your question, I think it is our mandate to bring affordable “mass customization” into construction and to use our research to ensure that individualization of design and construction is available for everyone.

[1] Yearly volumes: concrete 10 km3, fired clay 2 km3, timber 1.3 km3, steel 0.1 km3.

On this subject see also the newspaper contribution “Gewürze für mehr Nachhaltigkeit” of 25.06.2015 in “Tages-Anzeiger” (in German only).

Photo credit: Gramazio Kohler Research, ETH Zurich.

In September a new Master of Advanced Studies (MAS) ETH in Architecture and Digital Fabrication will be offered by the Gramazio Kohler Research chair at ETH Zurich. This one-year, full-time program focuses on digital design and full-scale fabrication using state-of-the-art robotic fabrication facilities at ETH. The MAS is embedded within the National Centre of Competence in Research (NCCR) Digital Fabrication, itself an ambitious research initiative at the intersection of architecture, engineering, robotics, material and computer sciences. Interested candidates are invited to apply until April 30, 2015.

The term “digital fabrication” refers to the seamless combination of digital planning with the physical fabrication process. The project data is sent to a machine, and directly implemented in reality. However, this exchange of information could also work in the other direction: the physical conditions could immediately influence the computer-aided designs.

For architecture, this opens up possibilities that were previously undreamt of, and which go far beyond purely design-related aspects. New construction systems, material systems, resource-saving production, efficient-yet-flexible engineering and construction processes, and a transition from mass production to customised industrial production all promise a decisive developmental step towards a sustainable building culture for the future.

Unlike objects produced by conventional computer-controlled production, architectural objects are typically larger than the actual production facility, they are always unique, and they are usually produced on site. As a result, research on this topic is confronted with completely new questions: How can the automated industrial robot in the factory hall become a reactive robot for the building site? What intelligent material systems and construction systems are suited to a robot-based additive (and thus waste-free) building technique? And what do the new planning and building processes mean for the future interaction between humans and machines?

The practicability (and thus the success) of digital construction will depend not only on research, but also, to a great extent, on experts who can ensure the transfer of knowledge into practice. This is why the NCCR Digital Fabrication, in conjunction with ETH Zurich, is launching the new Master of Advanced Studies (MAS) in Architecture and Digital Fabrication next autumn. As the education platform of the NCCR, this programme is embedded in the context of the latest research findings. In the NCCR’s unique robotic fabrication facilities, the students will also have the opportunity to research digital design and construction processes, and to implement these directly in large-scale prototypes.

More info: http://www.dfab.ch/education/mas/

If you liked this article, you may also be interested in:

• Swiss to invest almost CHF30 million in digital fabrication research over next 4 years
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