CAM Fingerprints as ornaments of construction

Robotic milling, EPS (expanded polystyrene foam) and concrete are the dancing partners in the newly defended PhD project by architect/industrial designer Johannes Rauff Greisen.

[Johannes Rauff Greisen in front of the industrial robot. Photo by Martin Kunzendorf, via]

As most academic titles, it's sexy: "Architectonic possibilities by robotic fabrication of formwork in concrete building". The project behind the title, however is great because it takes on an investigation of the architectural potentials of the technique by making lots of formwork and testing it and discussing this in terms of architectural applications as well as the challenges of actually using EPS as a mold for concret. The scope of the investigation includes scale issues as well as economic drivers for a new aesthetics.

Starting with the prototypes, Johannes was an Industrial Doctorate at the concrete centre at the Danish Technological Institute (TI). TI had purchased a robot which they had Johannes get well acquainted with - but furthermore the concrete centre has fully automatic but tiny version of an industrial mixing plant to make completely scaleable concrete mix designs. (Sensing my envy here?)

[Thousands of light transmitting fibers for the concrete formwork before the pour. Image from Johannes Rauff Greisen's research via]

One of Johannes' experiments is one of those that 'can't be done', namely making translucent and image/pixel transferring concrete. - Well, on a curved surface that is. I am not good at explaining it and the available image online are less than great, so have a browse through Johannes' well-illustrated paper for the Prototyping Architecture conference, which we both attended earlier this year. - Download the proceedings here ((90+ Mb))and locate the paper and lots of images on page 131.

[The curved concrete screen with embedded optical fibers displaying/projecting the image shown on the computer screen. - Trust me, you'll get it as you browse through the paper! Image via]

Cheap becomes ornamental potential

Another series of experiments deal with effectivity of the milling process. Often the aim with milled formwork - well the desire, anyway - is completely smooth and endless surfaces. One of the drawbacks here is price - the 'closer' the shave, the finer the tool, so to speak. In milling terms, this means that a finer milling tool would be needed for finer, more controlled surfaces. This is costly because of the time. - So, why not make a virtue out of the necessity and praise the crude patterns of the cheaper manufacturing to add an extra layer of interpretation on the concrete surface? What is at stake here, for Yours Concretely, is the robot version of stereogeneity which I wrote about here. 

[Fine patterns of milling or CAM fingerprints shown on the concrete surface (and my new nail polish). The image is by Rauff Greisen and reproduced from the anthology Material Evidence in Architectural Research, Eds Anne Beim & Mette Ramsgaard Thomsen]

[Coarser patterns of milling or CAM fingerprints shown on concrete surface. The image is by Rauff Greisen and reproduced from the anthology Material Evidence in Architectural Research, Eds Anne Beim & Mette Ramsgaard Thomsen]

Rather than fighting the inherent formal language of the milling tool, Johannes advocates the new aesthetic, almost ornamental language of a still new manufacturing process. He coins the term CAM Fingerprints in his dissertation as associated the expressed process of manufacture from coarser, cheaper milling.

Johannes sums this up:

At one end the scale is expanded by introducing fine detail and light emitting elements in the surface, elements which are so extremely small that they become a material component. At the other end of the scale, is introduced architectural use of a coarse milling, the so-called CAM fingerprint. Hitherto it has been the aim to obtain as smooth as possible milling. Targeted use of coarse milling is new and consists in consciously working with the robot's working pattern that forms a partially controlled technology fingerprint. This autonomous CAM fingerprint can be interpreted as neo-industrial digital ornament that share kinship with past ornaments - both the craft-based unintended ornaments and more random material contingent ornamentation. The Ph.D. thesis addresses these kinships openly, but concludes that the resource economy and practices around the coarse milling immediately lays considerably closer to the existing concrete building culture than the smooth milling. The Ph.D. project thus brings the robots opportunities closer to practical concrete buildings as architectural CAM fingerprints can reduce milling times and thus reduce the final manufacturing costs. Via

[CAM fingerprint consists of "milling tool's working patterns which are marketed in the mold surface and provides a technology footprint to the concrete surface. Here used CAM fingerprint as relief in an urban space concept (designed to SLA), consisting of a 'melting landscape' in concrete" cast with a membrane formliner via]

Johannes even suggests the term of a future concrete in a new-industrial context, robot concrete. This I am less convinced about but I really like the CAM fingerprints term and this eye for new aesthetics and ornamental potentials based on new techniques.

Despite the high-/low-tech discrepancy between fabric formwork and the 3d milled EPS this whole approach and love for expressing construction may tell you that we were in fact researching under the same roof, at the Royal DK Academy. Johannes was also my suuuper handy and cool cat co-teacher at several of the TEK1 workshops about fabric formwork.

Read an article (in Danish) about the perspectives of Johannes' research.