Knitectonics - Design Research - Chapter I

Knitectonics

Chapter I

Design Research

design research

Egg shell (1x)

Egg shell (450x)

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We commenced on our thesis research by looking at analogies in nature that correspond to architecture in their geometry, structure, growth processes, optimization, self sustenance and multi-functionality.

An interesting and intriguing example was that of the avian egg in its formation, structure and mechanics. The egg is formed in stages by continuous deposition and layering of various materials facilitating various functions. The deceptive smooth white surface that we see with the naked eye, at a microscopic resolution of 450 times is a striated surface of protein fibre membranes. The single shell has 8000- 10000 pores, which keep bacteria and dust away and the porosity enables heat and water exchange. Also the asymmetrical spherical form of the egg makes the structure stronger to resist breakage in certain axes.

The analogy of the egg enabled us to understand the concepts of single shell structure made of continuous fibers material and the economy of means wherein optimum amount of material is placed where it is required.

Monocoque Then began the research of single skin structures in the man-made world and the most basic example we identified were that of a coke can, aircrafts or a formula 1 car. These are structures, where the outer skin bears the loads on that structure and hence the concept of monocoque.

The term monocoque is a combination of the Greek root ‘mono’ meaning single and the french word ‘coque’ meaning shell, thereby meaning ‘a single shell’. The idea was first introduced in the aviation industry and was then carried onto other disciplines.

Monocoque structures

A coke can has no internal truss system and its aluminum shell is a monocoque. All of its strength is derived from the dimple in the base, without that it would collapse. The eggshells like; ostrich, hen and quail are all true monocoques.

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Gaussian Geometry

Zero Gaussian Curvature (Developable Surface Surfaces)

Positive Gaussian Curvature (Synclastic Surfaces)

Negative Gaussian Curvature (Anticlastic Surfaces)

Stinkhorn Mushrom

Video sequence of Stinkhorn mushroom growth

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Knitectonics Surface geometry of curved surfaces

The spatial structures are divided in non-rigid and rigid structures.

Tents, cables and pneumatics are light weight structures part of the non-rigid group, working on tension. While shells, folded plates and freeforms are structures working on tension, compression, bending and shearing.

Shell Scafolding _ Construction process

Shell Park Pavillion _ Felix Candela

The use of two ways structures, synclastic and anticlastic surfaces, applying Gaussian geometry presents an oppurtunity to achieve self structuring monocoques, without the need of additional structure. Shell structures designed by Felix Candela and Heinz Isler are the most iconic examples of monocoque structures.

But in spite of the lightness in aesthetics and structures, the popularity of single shell structures decreased in the 80’s, due to the complex custom made formwork required, which implied uneconomical numbers of labour, material and time. The challenge for us is to revive monocoques in architecture, by eliminating the need for a formwork.

Stinkhorn Mushroom Researching examplesin nature which demonstrated growth and self structuring, we found the stinkhorn mushroom.

These mushrooms are very diverse in appearance, but all of them share at least two features: · Some part of the fruiting body, at some stage in development, is covered with a foul-smelling slime. · The body arises from an “egg”, erecting completely after a few hours Sacklike volva; with a laced, white “skirt” hanging 3-6 cm from the bottom edge of the cap (sometimes collapsing against the stem).

The material continuity produced by the stinkhorn to create this structure, lead us to understand that self structuring forms can be achieved by employing a continuous material.

Stinkhorn mushroom membrane

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t heessi g d i sn r e s e a r c h

Material Behaviour Experiments Skin

Skin as Structure + Formwork

Structure without formwork

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For theIr apparent advantage of strength and continuity, we chose to work with composite materials. Our first set of analogue experiments were done to study material behaviour of matrix and reinforcement (the two elements of composites). In our experiments we evolved from creating skin to skin with structures and eventually forming skin as structure but without the use of formwork.

Our inference from the first set of experiments was that material and structure can be further optimized by differentiating fibers and hardener material distribution and density.

To understand fiber distribution and density, we began to look at industrial fields which use fibers. The textile industry gave us an insight into all the methods available to organize fibers, their properties and various production methods typically used.

Though glass fibers, with the advantage of low costs, are the most frequently used reinforcement in textile/fabric design, there is a variety of other fibers available; and the most advanced fiber based products are knitted and woven fabrics. Industrial machines allow for an additional high degree of variability, including mixing different types of fibers and the result is a two or three dimensional arrangement. These fiber processes have immense potential, but have been mostly underutilized in fileds like architecture and hence the impetus to research on 3D manufacture processes.

3d fibre manufacturing _ Science/Medical and textile Industry

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Fiber Fabrication Processes We studied some of the fabrication processes used in the textile industry for mechanically manipulating fibers into 3d fabrics.

Interweaving Interweaving is the intersection of two sets of straight threads, warp and weft, which cross and interweave at right angles to each other. Warping is by far the oldest and most common method of producing continuous lengths of straight-edged fabric. · Fiber Placement · 3d Weaving · Stitching Intertwining and Twisting Intertwining and twisting includes a number of techniques, such as braiding and knotting, where threads are caused to intertwine with each other at right angles or some other angles. These techniques tend to produce special constructions whose uses are limited to very specific purposes.

· Braiding

Interlooping Interlooping consists of forming yarns into loops, each of which is typically only released after a succeeding loop has been formed and intermeshed with it so that a secure ground loop structure is achieved. The loops are also held together by the yarn passing from one to the next. · Knitting

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    Fiber Spraying

The later ready-made is not necessary.

Knitectonics Disturbing and eventually quality reducing joins will be a High strength and form stability of the textile can be guar Final product has a lower weight and a more homogeneou Lower number of personnel and the clear reduction of cut

Typical applications of 3D-woven fabrics are half-finished p example hard hats, car interior linings or monocoques.

Fiber Placement

Braiding

3d Weaving

Mike Silver, Architects, Java-based taping patterns for With a reusable mould, a variety of patterns can be prod drives the fibre-placement process. Increased fibre plies buckling while allowing for a less densely packed fibre l and the wall, the frame and the panel no longer exist as penumbra (top image) also provides a flexible way to con

Fig. 6: Examples for application area of 3D-textiles Stiching

Knitting

Problems The writing of a database for the 3D weaving was very expens First, it had to be determined which length is needed for e done by manual measuring of the prototypes regarding wa Hence, the quality of a 3D-textile depends largely upon the ment. In a second step the weave constructions – adjusted to defined. These were21defined on the basis of experience value whole product the problem areas was apparent. To control an

design research

Textiles in Architecture History The origins of classical architecture, according to Semper, were traced to techniques of knotting and weaving. He postulated that a woven or knotted surface, that provided shade and delineated space, constituted the basis for the mythical conception of architecture.1 Innovations in material sciences and technology have overcome the limitations of textiles and also provided new sophisticated materials, thus causing ‘architecturalisation of textiles’ and ‘textilisation of architecture’.

“A new generation of giant scale textiles is at the core of a revolution in architecture” 2

Detail of Venice Landscape, Apollonio Domenichini (1715-1770)

Textiles were used only in interiors till the advent of high performance textiles in the 20th century. First enclosures created with textiles were tents and the other tectonic employment for them was as full- scale models and prototypes of buildings, which were then ‘solidified’ in stone, until Gottfried Semper revived textile tectonics.

The last century has seen the use of textiles in concept designs of Buckminster Fuller’s adaptable and flexible systems of architecture and in experiments of Frei Otto’s minimal nonlinear and optimised surfaces and forms. The analogy of textiles was often used for multilevel morphologies and utopian future cities. Postmodern world, with the advent of computers has been able to take qualities of textiles into building skins and now as tension based structures are at par with compression structures, lattice-like large- scale textiles are used for flexible skeletons and structural envelopes of buildings.

Frei Otto’s Self-Organization Experiement

Today designers are synthesizing with interactive technologies and textile methods to create dynamic, narrative and kinetic qualities in architecture.3 By the virtue of their material properties, they are conjectured to change conventional architecture; whereas the majority still requires conviction on how ‘soft’ textiles can compete with ‘hard’ construction materials.

We focussed our research on precedents where architecture coincides with textiles, why it should be considered a tectonic possibility and how the new ‘techno textiles’ could unite structure, geometry, aesthetics, material sciences, parametric design and digital fabrication.

The deep rooted presence and relevance of textiles in architecture necessitates the need to understand and acknowledge the theoretical works of the 19th century German architect, Gottfried Semper.

Seattle Library Curtain Wall_OMA

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Textile Theory: Gottfried Semper Gottfried Semper wrote extensively about origins of architecture.

In his book ‘The Four Elements of Architecture’ published in 1861, he categorised the technical arts into four classes, according to the technical procedures employed for different raw materials: textiles, ceramics, tectonics (carpentry) and stereotomy (masonry). The materials in their order move from light to heavy and flexible to rigid and also coincide with Felix Klein’s four layers of geometry, namely topology, isometry, similitude and projection.4 Semper deduced that textiles were the first order in the technical processes. He stated, “Textiles should undoubtedly take precedence as the primeval art, as textile types evolved within the art itself or were borrowed directly from nature, but all other arts borrowed their types and symbols from textiles.” 5 He redefined the wall as a spatial enclosure, rather than as a structural and critical tectonic member. “Hanging carpets remained the true walls” 6, he said and asserted that the woven walls were the original technique for creating architecture. He referred to building’s envelope as ‘clothing’; infact he found a common etymological root to the German words ‘dress’ and ‘wall’, both described as types of veiling and described the ‘knot’ as the oldest tectonic joint in history, based on idea of continuity of threads at joining points. 7

Semper Knots / Textile Theory

His most famous theory of the transformation of materials, says buildings are no longer made of textiles, that textile has been transmaterialized into stone and directs it to the fact that ideas do not inhabit matter, but other materials do, just as textile inhabits in stone.8 The historic Vitruvian paradigm of ‘firmness’ emphasized on architecture dominated by permanent, durable, hard, compression based structural systems. But Semper’s notions of textile based architecture promised a reorientation of architectural space, both metaphorically and literally, from a model based on the solid to the one based on the liquid or gaseous energy states of matter. In this transition, the material and energetic states of textiles with their common properties of surface continuities, lightness, softness, flexibility, thinness and fluid like dynamism, make them an apt material group for the expression and realisation of this new ‘spatiotheoretical’ paradigm.9 Semper established techniques in the textile system to deliver this materiality into architecture. The basis of classification of textiles in procedures was the attributes the material it requires i.e. pliable,

Gottfried Semper (1803-1879)

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tough, resistant to tearing; the textile processes contribute to the transformation of raw materials into products of suppleness and strength. The transformation material units have two uses, first being ‘to string and to bind’ and the second being ‘to cover and to enclose’.10 And so the forms arising from these are either a linear form or a planimetric form.

In congruence to contemporary architecture, the linear is referred to as thread or band or even nets and meshes and planimetric is referred to as a fabric or membrane and can be used with traditional techniques like weaving, tensile structures or new age techniques like fiber placement, air inflated structures etc.

After establishing the relevance of textiles and understanding the various techniques, it is imperative to recognize the contextual tectonic opportunities offered. Lars Spuybroek’s ‘textile way of thinking architecture’, facilitates this comprehension of textile in architecture beyond Semper’s symbolic realm of style and Frei Otto’s physical realm of engineering.

Textile Tectonics: Lars Spuybroek ‘Architectural design is not about having ideas, but about having techniques’.11 Lars Spuybroek goes a step beyond the Semperian theories and establishes the concept of ‘Soft Constructivism’,12 wherein he predicts that textile itself will become tectonic and soft elements will comprise a whole through collaboration (by teaming up, weaving, bundling, interlacing, braiding, knitting or knotting) and the whole thus formed will be rigid. He first used textiles, on the footsteps of Frei Otto, for analog computing to achieve self organisation and optimisation and equated textile techniques to computing techniques. Later he introduced the idea of textile techniques as design techniques, where textile becomes surface, geometry and structure. His conception of ‘techniques’ is not just about the traditional techniques of available fibers with their immediate relationality, but is also about new techniques made possible by new type of fibers and material assemblies.

Textile techniques are similar to morphogenesis; as one has to collaborate and communicate with the material, all the ideas are developed within the matter in the process of making and not from outside.13 The variations between two fixed ends: loops, knots and shifts – with their continuity and systemacy form figures that cause movement, orientation and deformations and these figures unite to form configurations. Unlike the classical subtractive approach, the continuum of material here works bottom up to add

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Form Finding Experiments_ NOX / Lars Spuybroek

Knitectonics elements into a form and the same figures can form surfaces or openings depending on configuration. With the material in consideration, it shifts from deformational to transformational and from system to patterned morphology, to what Lars Spuybroek refers to as ‘Parametric relationality’.14

Son O House _ NOX / Lars Spuybroek

Maison Folie _ NOX / Lars Spuybroek

The tectonic vocabulary of textiles offers surface, pattern and texture at a micro level and structure, volume and massing at the macro level and thus the ornament carries the load. ‘Topotectonic’ qualities, meaning tectonics of continuity and not of elementarism,15 of textile techniques create interaction between the part and the whole; the uninterrupted relationality articulates of the local and the global and facilitates communication and information transfer.

In the context of contemporary ‘parametric design’ a real textile technology could become a technique within digital technology 16 and that could then dwell in building technology. The ‘figures’ need not necessarily be fully materialized, but could be used to our advantage of creating transitions in ‘configurations’. Material states store information of the unit and the local neighbourhood and this information could be the parameter governing pattern, form and geometry, thus bringing techniques, ornament, structure and technology together. Coincidently, the Voronoi tessellation share the complex systemacy of textiles and the amalgamation of this coding to digital fabrication methods could cause emerging design. ‘Thats how the folk like aesthetics of textile techniques end up in advanced architecture’ 17

Textile Prototype: Carbon Tower Peter Testa and Devyn Weiser’s Carbon Tower is a design that culminated from a research on the tectonic possibilities of nonwoven, self- organising fiber strands. The prototype integrates computational geometry, material science, advanced structural engineering, free form robotic fabrication 18 as a generative process to create fiber tectonics.

Typically nonwoven textiles offer finer bonded fibers that are light weight and have augmented structural properties. Fibers have no pre- established topology, so form is an emergent property and structural morphology is a function of mechanical properties determined by fiber orientation. The continuous- discrete nature of the fibers provides them both geometrical and combinatorial characteristics that may be formed by quasi-autonomous agents acting independently or in collaboration with groups of agents, 19 thus creating all scales from individual strands to networked bundles.

Carbon Prototype Tower _ Testa / Weiser

For the Carbon Tower Prototype, a model for a forty storey office 25

design research

building, Testa & Weiser have developed a tensile building system using advanced composites, to ensure minimum material and maximum performance. Advanced fiber composites are typically constituted of a matrix material and a fiber material and are stiff, strong, light and formable. All fibres in the structure are continuous as they span the full height of the building and its facade is to be of transparent and translucent membranes. The construction approach here is top down, instead of the conventional bottom up; first the compression members or the cores are constructed using high strength steel reinforced concrete and then the structural skeleton is built from top to bottom. The structure is not assembled from distinct parts, but is woven together.

The hybrid structure has a flexible envelope with a rigid centre i.e. a tensile mesh or a woven structure is suspended from the compressive core.20 The cylindrical core volume is wound in both directions with forty thin helical bands of carbon fiber (a foot wide and an inch thick), running continuously from bottom to top to counter the vertical compressive loads. So within the tensile envelope, the compressive structure supports this compressive mesh of continuous pultruded sections, with carbon fiber cables to support floor slabs, such that the forty floor plates of laminated resin act in tension. So in a certain symbiosis, the floors and the helix, support each other and prevent the other from collapsing and provide an open interior plan.

The filament-wound ramps positioned around the structure allow pedestrian circulation, act as lateral bracing against wind and seismic forces, and are an integral part of the air-distribution system. The layered resin and silicone exterior skins provide natural ventilation and allow choreography of natural light inside, with the variations in membrane being opaque, reflective, translucent and transparent. A new pultrusion and robotic technology is being developed to weave the structural envelope on site. The bands comprising the helix could then be constructed by robotic devices working in tandem – a pultruder on each of the 40 vertically spiralling members, closely followed by a series of braiders that shape these same fibres into floors. The robots would weave simultaneously, moving up the steadily rising building floor by floor. 21

Carbon Prototype Tower _ Testa / Weiser

Future of Proto-textiles These are some of the unexploited qualities of textiles. Textiles in architecture could have an impactful response to the fast changing culture and society, as they can express and accelerate the changes to materialise built architecture that encloses dynamic, flexible, interactive and process based spaces. At a more literal level, textiles in architectural construction give us the opportunity to combine many multiple systems into a unified system making it more efficient, for instance the skin becomes both ornament and 26

Mel Weaver Script MIT _Testa / Weiser

Knitectonics structure. It promotes transparency, simultaneously links inner and outer spaces and ‘metamorphose the internal and external into a homogenous whole, such that inside/ outside divisions disappear’.23 The continuity of material makes emergent geometries achievable and ensures efficient and speedy construction, with an added advantage of construction waste elimination.

Though the origins of architecture are traced back to textiles, the long latency of textiles in architecture poses a challenge to its competence with the conventional materials. This challenge could be confronted with the re- engagement with the means of production and a resultant rediscovery of the craft for architecture. Advanced manufacturing techniques and digital technology are already available for the much established, age old textile industry. These could be morphed to suit progressive digital-designfabrication methods, which could then ‘self- program’ the textile techniques for parametric design.

A fundamental attribute of textiles ‘local relationality’, could be used to our advantage in a parametric system much similar to a cellular automata. Just as a cellular automaton is comprised of discrete cells in a neighbourhood and the configuration of neighbourhood is used to determine the next generation of cells, considering each loop or knot as a cell in textiles, generative information could be transmitted and that could formulate the ‘self- programming’ in textiles. This would impart inherent complexity and richness to the outcome. As Mike Silver says, “This kind of complexity is not dependent on the incessant differentiation of parts, but on the application of fixed rules in a discrete system that requires only two binaries, which could be sameness and variation, periodicity and aperiodicity, thereby making, architecture itself is computed”. 24 Another key trait of textiles, which could be exploited, is the fact that they are ‘multiscalar’ in resolution.

The system of textiles is similar to natural systems because here the mono- material can achieve the characteristics of multiple materials through ‘scalar differentiation and hierarchical build- up’.25 Infact, performance at a local and global scale, as noticed in nature, could be achieved with the new generation of smart materials.

Materials make up our built environment, and their interaction with the dynamics of the environment they are embedded within, results in the specific conditions we live in.26 High performance fiber and fabric materials at our disposal today, are much stronger, faster and lighter. The innovation in clothing is tending towards active garments, as opposed to the historically passive ones, garments that automatically respond to the external stimuli (stress, temperature, humidity etc) using smart materials. As textiles provide a flexible conduit, smart materials could be embedded in them to enable direct response to environmental influences making fibers a sustainable practice. Then we could even imagine a room made of responsive textile that would monitor and adapt according to the mood of the users! Possibly in the future biotextiles might reform architecture, as these biological fibers could have organic qualities of self- repair, growth and replication. 27 Textile structures bridge the gap between the transitory and the permanent, linking architecture, fashion, performance and sculpture in what is a highly attractive mix of the aesthetic and the functional.

The speed, liquidity and softness of textiles would change, accelerate and move the presence of architecture.

In the words of the distinguished French architect Dominique Perrault, “We should totally kill the idea that architecture is fixed. Architecture can and should change, where it is needed; it can be in a continuous state of becoming. I can imagine buildings that change their garments to communicate their changing function or ownership, or other aspects of architecture, to make buildings fit more flexibly.” 29

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Hypothesis

The agenda focuses on re-engineering standard design and construction processes, in favour of itinerant, adaptive and specific practices, to generate new rule systems and develop integrated solutions.

These novel methods would then be used to develop strategies for prototypical scenarios.

Our foremost objective is to achieve ‘economy of means’, such that material is placed optimally where it is required. Monocoques, where skin is the structure, visibly illustrate this; our aim is to extend this economy to other parameters of material, machine, infrastructure, energy, time.

The second objective is to create ‘self structuring forms’, such that formwork during construction can be eliminated. Material continuity is a potential method to achieve these, while economizing on material, time and energy.

These objectives are to be accomplished by reinterpretation of existing fabrication processes; in order to define a tectonic language on the basis of ‘material, machine and mannerisms’, which is at the core of the studio ‘Machinic Control’.

Design Intent Economy of Means ( Skin as Structure ) +

Material System

Fabrication Process

Fiber + Hardener

Knitting

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Knitectonics

Notes for Chapter I

1 Semper, Gottfried

2 Hanna, S & Beasley, PA

3 Garcia, Marc

‘Style in the Technical and Tectonic Arts; Or, Practical Aesthetics’, Getty Research Institute Publictions, Los Angeles (2004) page 248 “A Transformed Architecture”, ‘Extreme Textiles’, Edited by Matilda Mc Quaid, Thames & Hudson, London (2005) page 103 ‘“Prologue for a History and Theory of Architextiles”, Architectural Design ‘Architextiles’, Vol. 76 No 6, John Wiley and Sons, England (2005) page 16

4 Cache, Bernard 5 Semper, Gottfried

6 Semper, Gottfried 7 Garcia, Marc

8 Tramontin, Ludovica

9 Garcia, Marc

10 Semper, Gottfried 11 Tramontin, Ludovica 12 Tramontin, Ludovica 13 Tramontin, Ludovica 14 Tramontin, Ludovica 15 Tramontin, Ludovica 16 Tramontin, Ludovica 17 Tramontin, Ludovica 18 McQuaid, Matilda

19 McQuaid, Matilda

“Architecture of Geometry – Geometry of Architecture” (2003) ‘The Four Elements of Architecture and Other Writings’, Cambridge University Press, Cambridge, (1989) page 113 ‘Op.Cit., page 113 “Prologue for a History and Theory of Architextiles”, Architectural Design ‘Architextiles’,Vol. 76 No 6, John Wiley and Sons, England (2005) page 15 “Textile Tectonics: An Interview with Lars Spuybroek”, Architectural Design ‘Architextiles’, Vol. 76 No 6, John Wiley and Sons, England (2005) page 53 “Architecture + Textiles = Architextiles”, Architectural Design ‘Architextiles’, Vol. 76 No 6, John Wiley and Sons, England (2005) page 8 Op.Cit., page 113 Op.Cit., page 52 Op.Cit., page 53 Op.Cit., page 55 Op.Cit., page 58 Op.Cit., page 59 Op.Cit., page 55 Op.Cit., page 57 “Tectonics and Textiles”, Architectural Design ‘Architextiles’, Vol. 76 No 6, John Wiley and Sons, England (2005) page 100 Op.Cit., page 100

20 Testa, Peter Weiser, Devyn 21 McQuaid, Matilda 22 Garcia, Marc

23 Quinn, Bradley

24 Silver, Mike

25 Menges, Archim

26 Hensel, Michael Sunguroglu, Defne 27 Garcia, Marc

28 Simmonds, Tristan, Self Martin & Bosia, Daniel 29 Garcia, Marc

“Emergent Structural Morphology”, Architectural Design ‘Contemporary Techniques in Architecture’, Vol. 72 No 1, John Wiley and Sons, England (2001) page 16 Op.Cit., page 101 “Prologue for a History and Theory of Architextiles”, Architectural Design ‘Architextiles’,Vol. 76 No 6, John Wiley and Sons, England (2005) page 18.

“Textiles in Architecture”, Architectural Design ‘Architextiles’, Vol. 76 No 6, John Wiley and Sons, England (2005) page 25 “Building without Drawings: Automason Version 1.0”, AD ‘Programming Culture’, Vol 76 No 4, Wiley & Sons, London (2005) page 47.

“Manufacturing Performance”, AD ‘Versatility and Vicissitudes’, Vol 78 No 2, Wiley & Sons, London (2005) page 44.

“Material Performance”, AD ‘Versatility and Vicissitudes’, Vol 78 No 2, Wiley & Sons, London (2005) page 36.

“Prologue for a History and Theory of Architextiles”, AD ‘Architextiles’, Vol. 76 No 6, John Wiley and Sons, England (2005) page 19.

“Woven Surface and Form”, AD ‘Architextiles’, Vol. 76 No 6, Wiley and Sons, England (2005) page 84.

“Impending Landscapes of the Architextile City: an Interview with Dominique Perrault”, AD ‘Architextiles’, Vol. 76 No 6, Wiley & Sons, England (2005) page 34.

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Machinic Control 2.0 Design Research Lab v13 Archit ectural Association London Phase II Copyright Š Frozen Fibers 2011, otherwise indicated and used only for academic purposes.