Booklet: Lamella Flock (2010)

L a m e l la Flock

a research project in novel ways of fabri c a t i n g f r e e f o r m w o o d s t r u c t u r e s

CI TA : C e n t r e f o r IT and Architecture Ro y a l D a n i s h A c ademy of Fine Arts, School of Architecture

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lamella F lock Oslo, May 2010

L a m e l la Flock collaborators http://cita.karch.dk

lamella F lock Oslo, May 2010

the exhibition digital.material, oslo 2010

L a m e l la Flock

a r e s e a r c h p r o j e c t in novel ways of fabricating freeform wood s tructures

by Martin Tamke, Jacob Riiber and Stig Nielsen Lamella Flock investigates new possibilities of creating freeform structures in wood. Where this is at the moment achieved through the use of resource heavy production techniques using glue lam, complex joints, and 5-axis milling our research shows that freeform surface structures can be constructed by the use of straight beam elements. To achieve this we have utilized the principles of the traditional Zollinger lamella construction in combination with a non standardized production. Challenges arise from the complex interdependency of beam elements in the structure, and the non-linear relationship between requirements of structure, material and production. We propose an approach that utilizes principles of self-organization. This led to the development of generative digital tools that are informed by the physical 1:1 output including structural analysis, production/material knowledge, and geometric constraints.

Wood is one of the few truly renewable building materials - in terms of both materiality and production process. A high

degree of digital based automation and prefabrication makes wood industry very efficient. The backbone of the industry is formed by versatile and relatively inexpensive wood joinery machines that work with straight wooden beams. Our research has shown that complex wood structures can be efficiently made and assembled using straight beams. The key was the combination of traditional wood techniques with digital planning and fabrication.

We were asking: What would it take to produce wooden freeform structures with straight beams? What are the trade offs to be taken into account following this approach on all levels from design to structural behaviour and assembly? How can a process between an architects design environment and the crafts production expertise and machinery be setup and efficently structured? How is it possible to include knowledge of production and structural behaviour in an early design phase?

And is this bottom up approach a practical way for future building production?

Lamella Flock was exhibited as part of the digital.material exhibition at R.O.M Gallery for Art and Architecture, Oslo in May 2010. The exhibition was kindly supported by the Nordic Culture Foundation. Lamella Flock was further supported through the collaboration with Trebyggeriet.no, hsb-SYSTEMS gmbh, Hans Hundegger Maschinenbau GmbH, Knippers Helbigg Engineers and Prof. Christoph Gengnagel/ TU-Berlin Chair of structural engineering.

Thanks also to Michael Hensel, Oslo School of Architecture and Design, and Toni Osterlund, LundenOsterlund for their inspiring constribution to the research seminar.

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lamella F lock Oslo, May 2010

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lamella F lock Oslo, May 2010

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lamella F lock Oslo, May 2010

The german Friedrich Zollinger (1880–1945) invented an efficient lamella construction of wood beans in 1922. He was facing a massive need for new houses in his position as planning commissioner of the of city Merseburg in a time, with huge lack of ressources.

The Zollinger construction is in so far very appropriate for monolithic wooden joints as maximum three members join in one connection point.

In the Zollinger Construction a weaving like pattern creates structural strength through a high amount of interconnectivity

Ba s i c of the lamella c o n s t r u c t i o n The Zollinger construction is a type of Lamella roof construction (JS Allen) that was invented in the 1920s in order to create wide spanning constructions out of short pieces of timber.

The lamellas structural principle consists of a crisscrossing pattern of parallel arches of relatively short members. These are hinged together and form an interlocking network in a diamond pattern. The ingenuity resides within two constituents: the efficient joint system that minimizes the amount of shared meeting points

allowing for simple assembly and structural strength given by the interwoven beams.

Where similar systems, as mutually supporting beam systems (Popovich), usually form barrel or dome shapes work from the AA (Hensel, Menges) and Shigeru Ban (Tristan, Self, Bosia) demonstrates the principal ability of the system to form different shapes using the flex of the material, tolerances in the joint geometries and changes in the systems local orientation. In this bottom-up approach each element is threaded individually as it acts autonomously in a larger formation

Our own investigations revealed that freeform structures can be manually crafted from straight bamboo sticks by exploitation of tolerances in the joint. Yet this method relies purely on skill in crafting and negotiation with the physical model. The translation of the craft based approach into an architectural planning practice that would allow it to anticipate and fabricate geometry in relevant scale and tolerance became a main concern of the investigation.

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lamella F lock Oslo, May 2010

Previous work at CITA showed the possibility of modern wood fabrication techniques to create customized wooden joints on common timber machines. This bears the potential for mor flexible wood constructions. Where engineering in wood introduced long spanning constructions with wooden composites (GlueLam) mass customisation can form the foundation for more flexible types of wooden systems based on the conjunction of computation, digital fabrication, and traditional craft techniques.

Pr oj ect Parawood:

t r a d i tional wood joiner y as mean to ha ndle complexity http://cita.karch.dk

lamella F lock Oslo, May 2010

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lamella F lock Oslo, May 2010

The interactive design environment combines selforganisation of elements and intearction with outer sources as design intend and constructiuve constraints.

D e s ign of the s tructur e u s i n g s e l f o r g a n i s a t i o n Within a lamella systems all beams are structurally interconnected. This high level of interdependency prohibits traditional generative approaches. As initial approaches to generate the freeform lamella structure did not succeed we oriented towards bottom-up approaches instead. Our first experiment was a rule based linear distribution where element were sequentially inserted. This linear distribution led to extreme and unpredictable conditions. Due to the fact that in a networked lamella system one element is affecting all neighbours, this resulted in uncontrollable but compelling morphologies .

The problems within the mentioned experiments made it possible to state the requirements of our lamella system: A bottomup process with the ability of dynamic non-linear interaction where different design possibilities could be explored. We therefore introduced an understanding of a structure that is based on interconnected but autonomously behaving elements. This setup is in fact the basis of self organizing systems.

Our generative system is structured around interaction between elements consisting of four line segments coming together in a spiralling motion. In this way each entity exhibits within itself the non-linear relationship that unmistakably also defines the global structure.

The amount of entities, their sizes and a preliminary distribution of these as a diagonal grid in space are defined in the initialization process of the system. While running, the system is controlled through four behavioural algorithms that accumulate vector information. Each algorithm produces directions and velocities that interact to produce the overall movement and transformation of an entity.

The interface allows the model to dynamically interact with and inside an environment given by site, program, production and material properties. Manipulations are instantly answered by the model through topological change. These changes appear to the designer as a result of an internal reflection rather than direct answer. In this way designing starts by learning about the distinct character of the model and its behaviour. Feedback was integrated into the model which was becoming noticeably aware of its placement in the building process. The incoming information was handled in a pragmatic way where new insights were either encoded as internal conditions in the generative code or the visual interface was used for constraining the self-organizing system manually.

The principle of self-organization occurs at varying scales and within diverse domains of reality; living nature, non-living nature, dead nature, technology, and societies. Initially theories of self-organization as a tool where developed in the context of physics and chemistry. Later it was found that these ideas could be extended to the simulation of social insects, flock of birds or big group of humans. These simulations showed that problems can be solved by decentralized systems, comprised of many relatively simple interacting entities.

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lamella F lock Oslo, May 2010

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lamella F lock Oslo, May 2010

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lamella F lock Oslo, May 2010

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lamella F lock Oslo, May 2010

Test skĂŚring 2010 03 10

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S e t up of the digital ch a i n Production and design tools were linked in the production of the Lamella structure. Part of this digital chain was the direct implementation of an FE Analysis and the check for feasibility and structural behavior in advance. The structure is a temporary installation and no snow loads and moderate wind loads were assumed.

The stress distribution over the surface was analyzed and different underlying principles were verified. The negative gaussian curvature of the surface and the presence of a hyperboloid surface results in a rather stiff structural behavior. The free edges are not held by a stiff edge member which prohibits an overall shell behaviour. Due to its triangulation the load distributes free over the surface and an edge area is automatically formed which

compensated the missing edge element. This is a positive structural effect of the decision to take even distributed elements. As another free load distribution over the surface would require coverage with wood planks as in the classic Zollinger structure. As the installation was only temporary additional bracing elements were introduced. Their orientation avoids buckling by approximately following a continuous tension state.

Further research dealt with peculiar properties of the lamella structure. So it could be proven that the effects of imperfection between axis that are the result of the multi agents optimization process within the SO-system are negligible. The small deviations could furthermore be easily

grinded off the wooden beams if needed for constructive reasons.

Constructive reasons were as well the reason to use a basic method from Zollinger for this structure: The offset joint. As crisscrossing beams have to be connected to the same beam this is weakened in the middle. In order to reduce this a offset between the two opposite members is necessary. Since the distance puts significant in plane bending to the continuous member it should not be too apart. The optimal distance was evaluated and taken for the build up.

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lamella F lock Oslo, May 2010

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lamella F lock Oslo, May 2010

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lamella F lock Oslo, May 2010

P r o duction & Assembl y The intense development phase paved the way for a smooth production. The finished cutting data was send to the wood producer, who cut all elements in 3 hours and delivered the cut pieces to the site. The assembly strategy was based on the experiences made in the prototype and consisted of a preassembling of smaller units that were later lifted in place and connected.

Each beam had a small tenon of around a third of its depth at its ends and housing sin the connection point in its mid. The joints allowed for an easy and yet very precise positioning of the labeled beams. Once assembled the basic elements were already stiff. Specialized woodscrews could be applied without pre-drilling

and granted the necessary strength.

Self registering joints were crucial for the exploitation of digital fabrications precision as their guidance allowed precise assembly of elements without the use of measurement devices.

This allowed a two man team to assemble the structure in two days including the installation of foundations. A precise paper based documentation of all units in assembly order and several overall drawings with measurements for the foundations locations were the only documentation needed.

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lamella F lock Oslo, May 2010

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lamella F lock Oslo, May 2010

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lamella F lock Oslo, May 2010

d i g i tal.material: semin a r Monday April 26th 2010

Toni Österlund

Michael Hensel

As part of the exhibition we held a open seminar reflecting on digital practice in architecture. The aim for the seminar was to discuss the further framework of the research exhibition.

Toni Österlund is a Finnish architect working with the possibilities of digital fabrication and algorithmic/parametric design methods. He is a partner in a small, yet innovative architecture office Lundén Österlund architects with special interests in digital design strategies, the use of timber through computerized fabrication and implementing natural processes in architecture. He has written articles on publications and collaborated with the University of Oulu, Department of Architecture by organizing workshops for students on algorithmic design methods. He was part in setting up an international seminar, exhibition and publication, called “GENERATE – from algorithm to structure”, which displayed works and experiments on algorithmic structures. He is currently starting his Ph.D. studies in University of Oulu, Department of Architecture.

Prof. Michael U. Hensel [Dipl. Ing. Grad Dipl Des AA] (born 1965, Celle, Germany) is an architect, researcher, educator and writer. He is a founding member of OCEAN (1994) and founding chairman of the OCEAN Design Research Association (2008) where he currently serves as a board member and secretary.

He is currently Professor for Research by Design at AHO – The Oslo School of Architecture and Design in Oslo, Norway. Previously he taught at the Architectural Association School of Architecture in London (1993 to 2009), where he developed the curriculum for and co-directed the Emergent Technologies and Design Program (2001 to 2009). He held visiting professorships and innovation fellowships and taught and lectured in Europe, the Americas, Asia and Australia. His research interests and efforts include formulating the theoretical and methodological framework for Performance-oriented Architecture and developing a biological paradigm for design and sustainability of the built environment.

Seminar topic: Digital media is often seen as a way to abstract the world. But in design and fabrication digital tools allow for a new closeness between design and making. As manufacturing becomes increasingly computer controlled and as better and more solid interfaces between the design space and fabrication mature, a more integrated working practice arises. To enter into this practice, and to make use of its knowledge sharing and its ability to create new more sustainable building practice that lie outside the mass produced and the standardised, it is necessary to integrate this new practice into architectural thinking, designing and making. digital.material explores a new material nearness into our practice. Through this seminar we ask: how do we engage with this material sense, how can better crafts knowledge challenge our design paradigms and what happens when the architect become tool builder defining individualised design tools for non standardised making.

http://www.loark.fi http://www.generate.fi

www.performanceorienteddesign.net www.ocean-designresearch.net

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lamella F lock Oslo, May 2010

Mette Ramsgard Thomsen

Phil Ayres

Martin Tamke

Mette Ramsgard Thomsen is an architect working with digital technologies. Her research centres on the relationship between crafts and technology framed through “Digital Crafting� as way of questioning how computation, code and fabrication challenge architectural thinking and material practices. Her work is practice lead and through projects such as Slow Furl, Strange Metabolisms, Vivisection and Sea Unsea she investigates the design and realisation of a behavioural space. Mette is Associate Professor at the Royal Academy of Fine Arts, School of Architecture, where she heads the Centre for Information Technology and Architecture [CITA]. She has researched and taught at the Bartlett School of Architecture, the Department of Computer Science, University College London and at University of Brighton, School of Architecture and Design.

Phil Ayres is an architect and educator. He recently joined the ranks at CITA (Centre for Information Technology and Architecture, Royal Academy of Fine Arts, Copenhagen) after a decade of teaching and research at the Bartlett School of Architecture in London, and completing a PhD in Denmark at the Aarhus School. As a self-taught computer programmer, skilled machinist and maker, his work searches to construct complementary potentials between the worlds of the digital and the analogue. His teaching and research allow him to bridge the realms of representation, fabrication and interaction, and feed into his interest of developing exploratory design techniques that are often computer mediated, but always lead to physical output. Much of this work has been published internationally.

Martin Tamke, is Associate Professor at the Centre for Information Technology and Architecture (CITA) at the Royal Academy of Fine Arts, School of Architecture in Copenhagen he is pursuing a design led research on the interface and implications of computational design and its materialization.?Being interested in the making as well as the reflection on new strategies in architectural design he worked after graduation at the Institute of Theory and Design in Architecture (ige) at TU Braunschweig in 2003, where he got in contact with scientific research in interdisciplinary projects, mainly with Computer Science. Based on a deep understanding of architectural design and computational techniques he developed his practice between the speculative and the realization of architecture. In the recent years his practice took place in collaborative projects in different scales: from exhibition pieces, competitions and interiors, as the realization of a virtual news studio for the television company RTL to architectural projects. A 70m organic shaped infrastructural hub is currently under construction in Hamburg.

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lamella F lock Oslo, May 2010

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