Knitflatable Architecture: Pneumatically activated pre-programmed knitted textile spaces

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KNITFLATABLE ARCHITECTURE: Pneumatically activated preprogrammed knitted textile spaces ITECH M.Sc. Thesis

BARANOVSKAYA YULIYA Supervisors: Moritz Dรถrstelmann (ICD) Marshall Prado (ICD) Professor: Achim Menges (ICD)

University od Stuttgart 2014-2015



Master Thesis Project is developed at the Faculty of Architecture and Urban Planning of the University of Stuttgart within ITECH M.Sc. Programme under the supervision of professor and tutors from ICD (Institute of Computational Design) in a period 15.10.2014 - 20.10.2015

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CONTENT: ABSTRACT 07 01_AIM 09 02_CONTEXT 09 03_STATE OF ART 19 04_METHODS 35 05_DESIGN RESEARCH DEVELOPMENT 69 06_DESIGN RESEARCH PROPOSAL 106 07_DISCUSSION 120 08_OUTLOOK 124 09_ACKNOWLEDGEMENTS 129 10_BIBLIOGRAPHY 131 11_APPENDIX 129

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ABSTRACT The purpose of this thesis is to investigate the potentials of textile architecture through a multi-layered study of the knitting technique and to show how the pre-programmed surface pattern affects the global geometry while being inflated. The empirical part of the study was conducted through sets of experiments with various knitted samples activated pneumatically into a shape. Knitted fabric surfaces were formed into the cushion and later were filled with the multiple latex inflatables. The outcome of the system is a continuous element that bends according to the assigned surface differentiation and creates a spatial division. The multiplication of the elements with different geometrical behaviors and surface features can result in a larger scale architectural object that creates different spatial situations for inhabitation.

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01 AIM 02 CONTEXT

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CHAPTER 01

SHAPE FITTING

OPENINGS

architecture?

SURFACE COVERING SHAPE FITTING

I_001: Knitting for architecture? Diagram of the potential use of the knitted textiles for architectural application.

01_AIM The aim of the current project is to explore knitting manufacturing techniques in order to fabricate differentiated textiles and discover ways in which they could be activated pneumaticly to create architectural spaces. In recent years textiles have been introduced to architecture through the physical realm of engineering: those systems are able to integrate the surface suppleness with the structural toughness. Textile technique becomes a way of computing, surface becomes structure and structure becomes geometry (Lars Spuybroek, NOX) [1]. Textile manufacturing technique is a driver for the design and has a lot of potential. Knitted surfaces being produced as set

of rows containing series of loops can perform dynamic mechanical (stretching, elasticity) and kinetic (foldable creasing, curling) behaviour. Normally, knitted textiles are associated with the fashion industry and garments production. By itself a knitted garment is a very complex fibre system with different areas with various properties merging with each other. The questions we seek to answer are: What happens if we translate properties of knitted textiles to the architectural level? What if we convert the richness of the textile formation methods to building methods? Although the fabric itself lacks structural self-supporting properties, the use of a element integrated into the fabric system might compensate this absence and due to the great tensile properties textiles could turn into a competitive building material, that can 10


CHAPTER 02

DYEING

Direct to Transfer Garment Printing Roller Silkscreen Printing Silkscreen

Perrotine

SEWING

Mechanized Roller Synthetic Indigo Mercerization Bleach Improved Embroidery Machine Synthetic Dyes begin Embroidery Machine to be researched Double-lock sewing machine

Mordant block Roller Priting printing for more fabrics Roller Priting

WEAVING

Molas Machine looms Water-powered throwing machines

Nottingham Lace Machine Ikat Dying

MONOFILAMENT TEXTILE MAKING

Multi-thread bobbinet machine

Resists

Broadloom

Quilting Multi-thread knitting machine Frost’s Net Powered knitting machine

Drawloom

Indigo cultivation spreads

Lace

Patterned knitting on frame Hand-operated knitting frame

Upright Frame Loom

Crochet

Pattern Knitting Block Printed

Bags

Piling

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Patchwork Painted Fabric

Weaving

Caulking for waterproofing Needles, sewing FESTIVAL

Treadle loom

Applique

Embroidery

Cord Dye

Threads

Twined textiles

PREPARATION

Wheel spinning of weft yarns

Knotted netting

Spinning Wheel

Plaited Textiles

Linking and Looping Felt Improved preparation

Spun Fibers

Mechanized wheel spinning

Knitting

Sprang

Cotton Carding in Europe

Spindle Wheel

Splicing

Cotton overtakes linen

Lycra Polyester Acrylic Nylon Viscose

Multi-ply cords Cord Twisting bast fiber

vines, intestines, sinews

10000 BCE 40000 BCE

silk

MATERIALS

cotton flax, hemp, ramie wool

1000 BCE

1000 AD 1500 AD

2011 AD

xtile history diagram, World Textiles: A Concise History by Mary Schoeser, 2003 and 5000 Years of Textiles by Jennifer Harris, 2004 Figure 2.3 Textile history diagram. Developed from World Textiles: A Concise History by Mary Schoeser, 2003, and 5,000 Years of Textiles by Jennifer Harris, 2004.

I_002: Textile history diagram. World Textiles. A Concise History by Mary Schoeser, 2003 and 5000 Years of Textiles by Jennifer Harris, 2004

span over many meters, cover big surface areas, provide shade and support loads. The textile object is born in one continuous process of creation and manipulation. It reaches its final form in a relatively short time, ready to be installed and used.

New visions of architecture and urbanism were often accompanied or driven by technological developments, material innovations or dramatic changes in politics, society and economy (Manuel Kretzel, Polymorphic Matter, 2013) [21]. Based on their manifestation and visual character they are implicit in various architectural styles, each more or less representative of a certain period in time. Today’s society is extremely diverse, profound and interminable and therefore difficult to be presented by a single and defined image of our time (M Kretzel, Polymorphic Matter, 2013) [21]. Similarly, the rapid development of new technologies, the great variety of available materials and the inconsistency in combining these to create new spaces for a rapidly growing and evolving population leads to a confusion of architectural styles. This is why today is the right time to focus on the materiality. Material attributes, no matter how solid

02_CONTEXT

“Architectural design is not about having ideas, but about having techniques. Techniques that operate on the material level. It is about making matter think and live by itself.“ Lars Spuybroek, NOX 11


CHAPTER 02 01

visual and weather protection textiles as mats, blankets and wall hangings. Great significance and sacral use of textiles: birth, wedding and death Protection from cold, sun and insects

Funeral ceremony of Septimus Severus, Roman consecration medal

fence for animal pets, woven with branches

textiles that are used in outside areas to partially or entirely enshoud scaffolding or building facades in a vertical direction

775 BC

first manmade partition walls, later will be replaced by plant fibres and by thread spun from animal wool

exteriour wall

Stretchable lycraspanned over the semicircular bars anchored in the facade

new way of seeing familiar objects “revelation through concealment”

huts and wooden halls of the Tanguts are coverede in silk and fabrics along the cremation paths of East Turkestan

Building site collapse, Southampton, UK 1998

Christo and Jeanne-Claude Port Neuf Bridge Wrappingg,

211 BC

1610 Basilica di San Lorenzo enshrouded for the funeral of Enrico IV, Florence, Italy

1280 1425 Temporary festive hangings, Samarkand

2001 2002

1995 Christo and Jeanne-Claude, temporary wrapping Reichstag, Berlin, DE

1984

Shared living house Yaraicho Satoko Shinohara / Spatial Design Studio + Ayano Uchimura / A studio: “Liquid Facade”, Los Share Yaraicho, Tokyo, 2012 Angeles, USA, 2002 Infranatural, Jenny Didier

Design for the Pinault Foundation, by Dominique Perrault Architects, 2001

2003

2008

2012

protection from dust and falling particles,

Casa da Musica, Porto, Portugal, OMA, 1999-2004 Zenith Concert Hall, Massimiliano Fuksas, 2008, Strausbourg, France

ornate draperies decorated walls to emphasise the festive spirit and to make halls more habitable

curtain wall

is positioned behind large-area glass facades, providing light and visual protection, before used as protection against stone cold walls in the interiour

as sound absorbing wall covering fabrics

Anthony and Cleopatra Banquet, Jan de Bray, oil on canvas 1696

406 BC

V c.

custom to change the wall hangig according to the season: silk - cooling in the summer wool - gainst cold in the winter

41 BC

XV c.

the edges of the rooms were draped veiled with in extravagant temporary and permanent fabric draperies

textile interiour decoration was further reduced with the beginning of “New Objectivity” era

Bedroom of Queen Louise of Prussia, 1809, Karl Friedrich Schinkel, Charlotten Palace, Tent Room, Potsdam, 1830

Bauhaus Dessau, textile wall coverings, Gunta Stötzl

United Bamboo Store, Tokyo, Japan, by Acconci Studio, 2003

Farnsworth House, Plano, Illinois, USA, 1950-1951, Mies

Aurora’ VIP Restaurant Room. Fabric installation at Matsumoto Nagano, by Ryuji Nakamura, 2007

1930

end of XIX c.

XIX c.

wall hangings provided protection from cold stonewalls, were mounted behind benchesand chairs as back protection.

Ion by Euriptides, a huge tent in Delphi, interiours were clad entirely with fabrics. precisious tapestries

Showroom Elia Tahari, by Gisela Stromeyer, 2013

temporarily isolate interiour from the outside world, residents can change the appearence of the facade

1925

1950

introduction of heating, warming lining was no longer a part of the interiour spaces

1999

Villa Tugendhat, Brno Mies van de Rohe, 1930

2003

2007 2008 Bordello Bar Interiour, London, by Sam Buxton, 2008

2012 2013

Gala Event, Whitney Museum, NY, USA, by Gisela Stromeyer Design, 1999

flexible way of life

to provide temporary vision protection protection from the outside space preventing the feeling being lost

The dining area is surrounded by The dining area is surrounded by lenghts of fabric lenghts of fabric

myThrea Pavilion, Nike Fly Knit Collection Exhibition, by Jenny Sabin,2012

MATERIAL EQUILIBRIA Installation at ggggallery in Copenhagen, Denmark, ICD, Sean Ahquist, 2012

refers to a curtain that divides space, by opening and closing different spatial situations can be created partition wall

part of court rituals, curtains used to alternate between withdrawal and appearence

celebration by King Xerxes, antling of the space between columns as temporary festive decoration

traditional Japanese sliding walls spanned with translucent paper Office Veered, NY, by Gisela Stromeyer,1994

510 BC

V c.

antiquity

curtain is used to create interplay between concealing and reveling - to separate holy from unsanctified

XIX c. Partitioning heavy curtains were used as flexible door closings

Mantling of the space were widespead in Europe

1994

XX c. textile partitions started to be replaces by solid materials in Europe

2012 2013

Elie Tahari Spring Presentation, by Gisela Stormeyer, 2013

Tugendhat House, large living and working area were partitioned by curtaines as required without disturbing the unity of the whole space

Ideal House Cologne, International Furniture Fair, Köln, DE, by

simple forms of living were desired, heavy pleated textile mantles replaced by brighter, lighter curtains of voile and mousseline

room in room

refers to a space that can be opened and closed using vertical expances of textile that are mounted inside solid built spaces

antiquity bed curtain, curtain was surrounding bed from all 4 sides

V c.

Barocco Four poster bed as throne bed as the throne

Exhibition Design, the interiour space was divided using lenghts of fabrics

1789-99 French Revolution

1927 1927

Exposition de la Mode, Berlin 1927 Mies van de Rohe, Lilly Reich

Travelling Showroom, ex.Studio. Patricia Menses, Ivan Juarez, 2008

2005

2006

2008

Extention to School Complex, Boltschauser Architects, Alex Herter, 2006

Woman in the day bed, mosaic from Centocelle, 1 AD

I_003: Historical timeline diagram of the role of textiles throughout the history. For zoom in >>> see Appendix

and homogeneous they are, always build-up from certain mechanisms occurring on the micro level. Spatial design and the arrangement of rooms is still very much depending on social norms and proportional rules, that are based on the concept of an average human in terms of proportion, interests and behaviour. However, we are all different. The desire to stand out from the crowd of similarity becomes even more evident with regard to young generations, whose values are independence, flexibility and customization. Architectural textiles can be a key solution to respond to society`s fast-changing consuming and cultural demands, enabling the production of more dynamic, flexible, interactive, event and process-based architectural spaces. The flexibility of textiles introduces a new paradigm into architectural theory. In contrast to the static

buildings, they can adapt to the permanently changing needs of human beings. The tectonic of textiles is the tectonic of coherent continuity, rather than of separate elements, which are just connected. This is making it even more fascinating and causes it to behave as an organism. Textiles have many functions and respond to many needs that architecture cannot always manage by itself. The architecturetextiles relationship provides a unique and illuminating account of both the present state and possible future of architecture and the city (ArchiTextiles, AD, 2007) [2]. For centuries textiles as a material group were excluded from most of the main architectural theories. Textiles were kept indoors, within interiors. This trend lasted until the advent of new high performative materials: textiles went outdoors. The architecture 12


CHAPTER 02

I_004: Skin Graph Studio, UK

paradigms reoriented architecture from solid to liquid. The material qualities of textiles make them particularly relevant to this new para digm of spatial design. Modern theorists define the following key words for the new architecture: soft, flexible, networked, continuous, dynamic, folded, adaptable, translucent, tensile, pneumatic, knitted, elastic, interactive, draped, flowing, fast, strong, smart.

“A new generation of giant-scale textiles is at the core of a revolution in architecture”. S Hanna and PA Beasley “A novel architecture strategy, active knits, provides complex three-dimensional distributed actuation motions with expanded operational performance through a hierarchically organized structure of cellular networks of interlacing adjacent loops of a single smart material fiber.” 13


CHAPTER 02

Thread configuration of a mes in a simple linking 2/2

Interconnected looping in the third turn

Interconnected looping in the third turn

Simple crochet stitch (face & reverse)

Simple linking

Simple looping with S crossing

Simple looping with S crossing

Plain crochet stitch

Linking on a foundation

Simple looping on a foundation

Simple looping on a foundation

Double crochet stitch

Twisted linking (triple linking)

Twisted looping with S crossing

Fishnet knot

LINKING

LOOPING

KNOTTING

CROCHET

I_005: Mesh formation techniques classification with a continuous element of limited and unlimited lengh

02.01_TEXTILE TECHNIQUES CLASSIFICATION Humanity gained an enormous experience in creating fabric sheets from fibers. Nowadays we are able to observe more than 50 different methods of creating sheet materials from filament. All techniques can be roughly divided into several groups depending on the type of the process and amount of participating fibers. The first big group is mesh formation with a continuous element of limited or unlimited length. Here the fabric is created from a single fiber with a single tool (needle or simply hands) and this method does not require an estimation of the size of the final fabric: the process is continuous and can be interrupted at any stage - having produced a complete fabric piece. Examples: linking, looping, knotting, crocheting, knitting. Another large group of textile

techniques is called mesh formation from sets of elements (multiple thread groups, warps and wefts). In this case multiple thread sets are needed for fabric creation and most likely a loom is required for accomplishing the process. Examples: plaiting, weaving, coiling etc. Apart from that, some techniques from both groups can be combined and transformed to advanced textile techniques. Different methods derive different properties of the resulting textiles. Some techniques are faster than others and some require secondary tools (looms, frames). Certain methods give more freedom to the designer, while others might cause some restrictions. In order to evaluate the textile fabrication methods, it is nessesary to set some parameters of the desired fabric qualities. The first is an ability of fabrics to expand in dimensions, i.e. how elastic the fabrics are. 14


CHAPTER 02

Plain knitting right

Right angle plaiting in a plain weave

Encircled coiling, wrapping around adjacent elements

Warp twining

Plain knitting left

Six strand braid

Linked coiling through mesh of active element

Countered weft twining with discontinuous wefts

Crossed knitting (face and reverse)

Active-passive intertwining

French knitting on a stitck

Active-active intertwining with braiding

Coiling with clove hitches

Slit tapestry

KNITTING

TWO DIRECTIONAL PLAITING

COILING

ADVANCED TECHNIQUES: WARP

Simple looped coiling, interlocked with mesh of active element

Openwork tapestry with displaced warp

I_006: Mesh formation techniques classification with the sets of elements with passive and active systems

Methods that are using loops for sheet formation will produce more elastic textiles due to the lack of fixed connections. All loops are free to readjust the tension between themselves. On the other side the methods that use straight continuous less flexible elements are most likely to end up with less drapable textiles. Another parameter that is important for design evaluation is the ability of textiles to vary the density and create openings. Loop based methods are more suitable for those design needs rather than plaiting techniques due to their fabrication flexibility within the single stitch, as well as the interconnectivity between the loops. The next crucial aspect of assessing the methods is the time costs and continuity of the process. Loop based fabrics are easier and faster to produce and do not require large additional tools and machines like they are needed for weaving, The continuity of the

process allows to interrupt the knitting at any moment and finish the piece. For the current Master Thesis Project the knitting technique was chosen from the wide range as the main technique because of the following reasons: - due to elastic properties of the resulted fabrics, - the high ability of differentiation to vary density and elasticity and create openings, - the relatively fast and easy fabrication process, - the existence of the affordable machines and tools and continuity of the derived geometries.

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I_007: Bertram of Minden, “Knitting Madonna”, (detail of Annunciation from the right wing of the Buxtehude Altar) 1400-1410.

02.02_HISTORY OF KNITTING, KNITTING AND NALBINDING. The word “knitting“ derives from the Old English cnyttan, which means “to knot“. In the Middle Ages in Europe knitting was gaining popularity very rapidly. Unlike weaving, it did not require cumbersome or expensive equipment. With a few pieces of wire and some colored thread, knitting could create anything from elaborate brocade-like designs to nicely fitted stockings to warm woolen caps. The earliest pieces of surviving knitting date back to 9th-11th century. For a long while the early story of knitting was complicated by the confusion of knitting with another craft, nalbinding. Nalbinding had been developed for a much longer time, and, what is more, it can create textiles that look quite similar to knitted ones. Nalbinding is a series of interlocking loops, made with a threaded needle and cut

lengths of yarn or thread. (Tournaments Illuminated 165) [19]. The main structural difference between nalbinding and knitting is that in nalbinding, the end of the yarn is passed through every stitch. Knitting, on the other hand, is constructed from a continuous thread; and a loop, rather than an end, is pulled through each stitch. The prevailing theory on the origin of knitting is that it probably evolved out of nalbinding, when someone realized that by not pulling the end of the yarn through each loop, one continuous thread could be used for the entire piece. Like nalbinding the earliest knitting was probably worked in the round to make cylindrical or tapered shapes, such as stockings or hats. Knitting requires a tool of some sort to pull a loop of yarn through a stitch, and it also requires some sort of device to hold loops in proper sequence. All the loops are made in a row of stitches. 16


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““ She has taken knitting out of the socks-and-sweater doldrums to prove that knit fabic can be a blanket, a pillow, a large piece of art....she demonstrates that knitting is a creative medium of self-expression.”” Jack Lenor Larsen, textile designer

I_008: Mary Walker Phillips, Lace Panel, Art Institute of Chicago, 1960s.

A straight piece of wire can easily perform both functions. So we most often see knitting done on those pointed sticks that are usually called knitting needles. Knitting also can be done on a frame, usually made from one or more pieces of wood, bearing a row of small nails. Each nail holds a stitch, and a separate needlelike tool is used to pull a loop of thread through each stitch. Until the 1500s, knitting was used mostly for small items, including bags, hats of all kinds, long and short stockings, mittens and gloves. Later on there are records of the use of knitting for the larger scale fabrics.

02.03_MARY WALKER PHILLIPS AND KNIT REVOLUTION IN 1960s Mary Walker Phillips is an American artist who took the utilitarian craft of knitting on to a new level, proved that knitting can be something more than just socks and sweaters. She gave a bold new life to knitting as a modern art and her works are now exhibited in several museums around the world. What Miss Phillips did, starting in the early 1960s, was to liberate knitting from the yoke of the sweater. Where traditional knitters were classical artists, faithfully reproducing a score, Miss Phillips knitted jazz. In her hands, knitting became a free-form, improvisational art, with no rules, no patterns and no utilitarian end in sight. (Margalit Fox, New York Times, 2007) [20]. 17


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03 STATE OF THE ART

Over the last decade the attention of designers and architects increased towards textiles. Professionals have been rethinking the potentials of textiles and have tried to develop the technology to obtain new and better architectural materials for higher performance. Textiles open up wider possibilities for design application that traditional materials were not able to. In this chapter we will present a range of several projects related to knitting textiles, as well as a wide diversity of the various textile activation methods.

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I_009: Jenny Sabin, MyThead Pavilion, Nike Fly Knit Installation, 2012

03.01_JENNY SABIN, myTHREAD PAVILION, NIKE FLYKNIT Inc. Jenny Sabin is an innovator who works at the intersection of art, architecture, design and science. There are instant similarities in her approach to the work of Nike’s Innovation Kitchen, where disciplines from different fields are brought together with a view to re-thinking basic principles and approaches to design challenges. Nike Flyknit uses simple threads to create a complex formfitting structure on a performance-enhancing shoe (myThreadPavilion, Jenny Sabin Studio 2012) [13]. Sabin’s fusions of science, art and technology has opened the door to new ways of thinking about structure and the relationship of the body to technology. Bio architecture and digital architecture deliver solutions, new understandings, new forms and a way for maths and generative systems to investigate the

complexities of natural form and internal geometries. Using Nike+ FuelBand technology to collect motion data from a community of runners during a Nike Flyknit workshop, Sabin — in collaboration with the runners — transformed the patterns of this biological data into the geometry and knitted structure, based on prototypes developed during the previous workshop sessions (myThreadPavilion, Jenny Sabin Studio 2012) [2]. The whole structure can be described as a complex system of knitted tubes that are held by sets of aluminium rings on one side and that are sewn all together on the other side. The resulted installation it is a wall-like double layer structure with openings. In this case an external tensioning system keeps the structure in place.

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I_010: Jenny Sabin, MyThead Pavilion, Nike Fly Knit Installation, 2012 (details of the project)

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I_011: Yuliya Baranovskaya, Ansis Sinke, Annie Scherer, KNITWIT Workshop on EASA 015, Valletta, Malta, 2015

03.02_YULIYA BARANOVSKAYA, ANSIS SINKE, ANNIE SCHERER EASA 015 KNITWIT WORKSHOP in VALLETTA, MALTA. The design workshop led by Y. Baranovskaya, A.Sinke and A.Scherer was part of the larger event EASA 015, held in the August of 2015. The workshop’s aim was to investigate the design opportunities of the modular knitted architecture and prove the concept by building a 1:1 scale structure. The knitted tubular element was considered as a coherent unit for the growing canopy structure. Multiple elements were attached to form the double layer surface having aperature openings. The design outcome was a result of varying several parameteres: scale and length of the components, direction of the structure growth, tentioning points as well as colour indication. The circular knitting machine Addi Express was the main

tool to fabricate the units. Depending on the way machine is used either for circular knitting or for flat - there is a way to control the scale of units. The smallest seamless unit is being produced directly on the machine in one go. Scaling up is happening if multiple rectangular sheets are attached together for creating a bigger hyperboloid. Each element is attached to the neighbouring one in 6 points of the upper and the lower edge. Apart from the width parameter, the length was controlled by the amount of knitted rows, which would allow the thickness of the structure to vary.

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I_012: Yuliya Baranovskaya, Ansis Sinke, Annie Scherer, KNITWIT Workshop on EASA 015, Valletta, Malta, 2015 (details of the workshop)

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I_013: Sean Ahlquist, INSTALLATION: “MATERIAL EQUILIBRIA: Variegated Surface Structures�, 2012

03.03_SEAN AHLQUIST_MATERIAL EQUILLIBRA Sean Ahlqiust started his textile experiments during his doctorate studies at University of Stuttgart, in the Institute of Computational Design. This particular project focuses on the relation of the articulated material and differentiated structural form. Through the spring based modelling environment the researcher is able to control and manipulate the behaviour between tensile structure and active bending element. In this case the textiles are supported by the fiber reinforced bending rod that stabilises the system. The fabric adjusts to the tension and distributes itself according to the tension loads.

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I_014: Sean Ahlquist, INSTALLATION: “MATERIAL EQUILIBRIA: Variegated Surface Structures”, 2012 (details of the project)

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I_015: Manuel Kretzel & Ivana Damjanovic, Animated Textile Workshop, Swedish School of Textiles, 2012

03.04_MANUEL KRETZEL & IVANA DAMJANOVIC_ ANIMATED TEXTILES Animated Textiles was a five-day workshop held at the Swedish School of Textiles at the University of Bor책s in September 2012. During the workshop the tutors together with participants explored the various combinations of electroactive polymers and lightweight textile systems to create animated surfaces, structures and assemblies. The supporting frames of the structure contain an electroactive layer (dark brown). The components that performed the best behaviour and highest deformation were picked to be attached to the textiles. 26


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I_016: Manuel Kretzel & Ivana Damjanovic, Animated Textile Workshop, Swedish School of Textiles, 2012 (details of the workshop)

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I_017: Nike Fly Knit Shoe, Lunar 2, NIKE Inc., 2012

03.05_NIKE FLY KNIT SHOES In 2012 the sports company NIKE Inc. introduced to the world innovative running shoes that are knitted as one piece. This new technology made NIKE FLYKNIT Shoes extremely lightweight compared to the previous models that contained a lot of unnecessary, sewn together components. The knitting technology used allows designers to differentiate the surface according to the performance of the shoe. The surface of the shoe is the single element which has openings and reinforcements where they are needed. For the global reinforcing NIKE creates little tunnels, where later stronger threads will be passed through to take bigger forces to the sole and provide biggest strength and stability of the shoe. This new technology can definitely be converted to architecture and

allows us to build lightweight but very strong structures. In addition, the new way of producing shoes leaves less waste from fabrication, which makes the knitting technology extremely efficient and suistainable in the era of recycling and saving resources.

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I_018: Unfolded state of the Nike Fly Knit Shoe, Lunar 2, NIKE Inc., 2012

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I_019: Mette Ramsgard Thomsen, Cad Cam Knitting, CITA, Copenhagen, 2010

03.06_METTE RAMSGARD THOMSEN, THE LISTENER The Listener CNC Knitting is the project that explores the idea of a textile membrane that has an inherent capacity to sense and react to its surrounding. Listener is collapsing the idea of the controlled and the controlling, Listener is produced of a material that has its own, autonomous, relationship to its environment. The material becomes sensitive as it registers changes in the conductive flow through the material. As the material moves, or as users touch and interact with the material, the sensor is actuated, which in turn informs a microprocessor that ultimately switches on and off an air blowing device.

The textile is treated as a composite material that - through its inherent conductivity that allows for the passing of computational signals, but also through its exceptional structural strength, and through its treatment - gains new properties. (Mette Ramsgaard Thomsen, 2010) [13].

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I_020: Mette Ramsgard Thomsen, Cad Cam Knitting, CITA, Copenhagen, 2010 (details of the project

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I_021: Fynn Freyschmidt, Pneumatic knitted connector, UdK Berlin Diploma Project, 2014

03.07_FYNN FREYSCHMIDT_PNEUMATIC KNITTED BIKE HELMET

The developmnt of the designer is opening new opportunities for compact contractile design.

Fynn is a product designer who believes into phantom potential of the air: it is widely availible and environmentally harmsless. For his Master Diploma Project he created a pneumatically contractile knitted fabric out of PVC-pipes. As soon the air is launched into pipes the knitted mesh compresses very tightly. Semi-finished products can be spontaneously joined together and be combined into different types and functional structures. For example in his Pneumatic Knitted Connectors, where the wooden elements are tightly held between the filaments of the knitted mesh. The process is completely reversible and the object can be easily deflated and pumped again with the regular bicycle pump. 32


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I_022: Fynn Freyschmidt, Pneumatic knitted connector, UdK Berlin Diploma Project, 2014

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04 METHODS, SYSTEM, TOOLS, METERIALS

In order to be able to study textiles it is necessary to know the knitting technology and being able to produce textiles. The first semester (WS 2014-2015) Thesis Preparation Stage was devoted to go through a physical prototyping in order to understand the way knitted textiles function and what can be contributed to the process. Second semester’s (SS 2015) focus was on the application of the discovered textile fabrication methods to produce three-dimentional geometries by pneumatic activation.

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Kenner knitting machine, 1967

Wool yarns

PRYM Round knitting machine

Knitting needles for a manual knitting

I_023: Toolset # 1, Manual and semi-automated tools that were used in the beginning stage of the project.

04.01_TOOLSET # 01 The first set of tools included manual needles as well as semi-automated simple knitting machines (a Kenner, retro version from 1967, USA and a more modern circular knitting machine, a PRYM). The amount of active needles in the flat Kenner machine is 30. The circular knitting machine has 42 needles in the circle. Any knitting machine functions as an interaction between the knitting moveable carriage and the set of needles, that are pulled into the front depending on the carriage settings. The difference between the circular and the flat machine is that in the second the needles are arranged flat one next to another. The way of knitting by hand and with the machine differs greatly: especially by speed a knitted piece is accomplished, as well

as by way of manipulation and programming the textiles. With the machinery knitting it is possible to make changes to the whole row, while with the hand knitting the knitter focuses only on the active knitting area (tip of needles) and applies changes only there. After producing several samples on both of them, we found that flat knitting machine is more flexible in terms of manipulation and control. Before the row is knitted, the knitter can adjust the sequence of loops in the row manually (in the semiautomatic knitting machine) or by the automatic carriage (like in Brother KH 930). In the circular knitting machine the manipulation of the sequence of loops is more tricky and requires rebuilding the carriage that picks needles. All the possible modifications of the fabric are possible only with the manual manipulation of the loops while knitting. Needless to mention that all the manual interraction is quite time consuming and 36


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I_024: Knitted samples produced with the semi-automated knitting machines: Kenner (left) and PRYM (on the right)

not very precise due to the lack of automation in the process. The mistakes are possible to occur since all the counting is happening manually and may lead to inaccuracy. The resulted fabric samples are presented in the picture above. There is a cylindric knitted seamless tube (on the right) and the flat knitted sample with the differentiated densities (on the left). Although the circular knitted sample looks more interesting and three dimensional, the flat knitting process shows bigger freedom for manipulating the fabrication of textiles.

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+ AYAB Shield

USB connection to PC

Arduino UNO

Floppy disc of the machine is removed

K-carriage (knitting)

Needle bed, 200 needles

gauge 4,5 mm

I_025: Toolset #2, Knitting machine BROTHER KH 930 connected to the PC with AYAB Shield and Arduino.

04.02_TOOLSET # 02 With the gaining complexity of the knitted textiles appeared the nessesity to upgrade the tool that was used for the thesis development. The manual knitting machine was smaller in dimensiones and did not allow to achieve a full control of the fabricated textiles. All the manipulation of stitches was happening completely manually: the knitter needs by hand to transfer stitches to the new location. The manual process would limit the development of the textile system and the potential outcome. The next machine to use was Brother KH 930, from 1987. Although the Brother Company suspended the production of knitting machines back in 80`s, nowadays there is still a possibility to buy programmable machines second hand. This particular model of the

machine allows to produce textile pieces width up to 200 needles and control the selected needles with the help of a programmable knitting carriage. This carriage is connected to the floppy disc of the machine through the circular metal belt that runs on the back of the machine and tells the disc which needles are passed. Originally this machine comes with 555 preprogrammed patterns that are provided only for garments fabrication (fairisle patterns, stripes, roses etc), which has nothing to do with the proper control of the differentiation of textiles unless the machine is hacked. To hack the machine, the first step is to remove the original floppy disk of the machine (internal “brain� of the machine) and replace it with Arduino UNO+AYAB-Shield Sandwich. This way the machine can be connected to the computer via USB and through Python programming receive signals in real time. Each row the knitting car38


CHAPTER 04

I_026: Knitted sample produced with the automated knitting machine Brother KH-930

riage travels on the needle bed the GUI (Graphic User Interface) tells the number of a present row and percentage left. With the additional L-carriage (lace carriage) it is possible to transfer selected needles and create openings. Another advanced option with the programmable knitting machine is the control of the direction of the knitting process. The next chapters will show all the fabrication possibilities and manipulations of the amount of rows in each direction. At some point the knitting can be stopped in the middle of the width of the piece and “branched out“ to another half. After that it is possible to come back to the left non-knitted part and proceed to knit it differently to the previous one. Using the same method of “HOLD“ it can be recursively branched out and merged back again to create vertical openings. Later in the next chapters we will show all the fabrication possibilities

and manipulations that exist to create interesting three-dimensional shapes and various effects. The fabrication of one row takes 1 sec to knit (plus-minus 5-20 sec) depending on the preparation process, but generally the knitting is faster with the automatic knitting machine. That directly effects the amount of project development that can be obtained in the smaller time frame. Above an example produced with the Brother KH 930 knitting machine is depicted. Samples perform high quality and consistency lopp size and tension, as well the high level of the pattern complexity. Additionally the attachement part Brother KR 830 was used. It allows to create rib structures and apply different tension on the main and secondary bed. 39


CHAPTER 04

bind off 16

bind off 6

bind off 3

stitch map

knit bind off

I_027: Binary programming of the knitting textiles, relation between the code and the resulted fabric.

04.03_BINARY TEXTILES

Textiles and computers have a long relationship. Around 1725 the first punched cards (cards with the circular small openings) were used by Basile Bouchon and Jean-Baptiste Falcon as a more robust form of the perforated paper rolls then in use for controlling textile looms in France. In 1801 Joseph Marie Jacquard invented first jacquard loom, which became basically the first ancestor of computers. This because of it’s capability to programme a pattern using punched hole cards with a binary system, no hole equals 1, one hole equals 0. In 1832 Semen Korsakov was the first who used the punched cards in informatics for data storage and search. Ten years later two scientists, Charles Babbage and Ada Lovelace, created the basis of the modern computing - the memory and the programmable calculator and called it “Analytical Engine“. The idea was to use same jacquard punched cards but for the machine to read a set of sequential instructions.

The punched cards are still used in some lower models of knitting machines where it is possible to programme a repeatable pattern for a jacquard knitting. The holes push the needles in a certain position. Since then nothing has changed. Textiles (knitting and weaving) are still a mathematical construction and require some sort of a punch card: either a material or a virtual one. The Brother knitting machine requires a black and white pixel map (low resolution image, max 200pix wide), where the width of the image in pixels amounts to the needles in work, and the height of the image in pixels is the amount of rows. All this is loaded to the graphical interface of the AYAB-Shield controller and after some button manipulations the machine is ready to knit what is pre-programmed in the virtual punch card. For the creation of the lace pattern, the needles are selected in a odd manner, which means that on the selected needles the openings will be created (with the L-carriage). The odd sequence is due to the mechanical restrictions of the openings. There should always be a stitch next to the

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CHAPTER 04

knitted fabric mesh

enlarged detail of knitted mesh

loop (stitch)

abstracted quad mesh

mesh face

I_028: Knitted textile mesh abstraction into a quad mesh

opening in the row in order to hold the opening in place. After each time the carriage finishes the row, the AYAB-Shield is making a sound, indicating to the knitter that the row has been processed and it is ready to go to the next row. It is very important to hear that sound to avoid mistakes in the knitting process.

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I_029: Yarn USHI WOLLE, 3.5-4.5, white. polyacryl 100%.

04.04_MATERIAL SYSTEM

In terms of material use, the project is focusing on the development of a fibrous system where the performance of the structure is an outcome of the fiber-fiber arrangement rather than the filament characteristics. That means that the whole range of elastic stretching yarns that can change the length under the pulling loads are not considered in this project. It is more important to evolve the fibrous system that can vary the properties of the different areas with the same single filament, rather than change the fabric internals by mixing distinctive yarns within one mesh. During empirical experiments it was noticed that non-elastic threads that contain a bigger percentage of polyacrylic inclusions are more suitable for geometrical studies. The higher ratio of polyacryl is causing bigger friction between fibers which means that in a relaxed state knitted mesh is tending to shrink. The knitted surface produced out of the yarn with

the polyacrylic (or wool) content is significantly more elastic than the one made out of cottom threads. Cotton made fabrics usually have a smooth surface and are much stronger, but form a less elastic surface due to the low friction between loops. The diagram on the right is representing the comparison material studies, during which it was concluded to use the 100% Polyacryl yarn for the all further experiments.

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digital simulation of the material behaviour

physical samples

marco image of the material samples

50% cotton 50 % polyacryl

100% polyacryl 75% wool 25% nylon 50% nylon 50% polyacryl I_030: Comparison of the knitted fabric shrinkage depending on the used material,

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CHAPTER 04

JOINING

SPLITTING

INTEGRATION

FOLDING

PROTRUSION

DENSITY

I_031: Basic main classification of the flat knitting fabricational concepts

KNITTED FABRIC SURFACE DIFFERENTIATION METHODS

After the technological studies were accomplished and the technical issues figured out, it was necessary to move to the actual prototyping. In the early stage of the method developments various flat knitting strategies were explored.

04.05_OVERVIEW OF THE FLAT KNITTING FABRICATIONAL CONCEPTS In the current subchapter several fabricational methods to make various knitted textiles will be presented in categories. Each of

Some of the mentioned concepts are sequential, which means that the sequence of fabrication considered as major principle. It is mostly about PROTRUSION, SPLITTING and JOINING concepts. Others focused more on the translation loops to the neighbour needles to create openings or reduce the dimensions of the knitted piece. Third ones required special additional tools - like a second knitting bed on the machine (for the FOLDING concept). A few concepts needed another second element to be embedded into fabrics to make it complete. This could be a stronger thread or active bending element. In addition, the design potential of fabricated knitted textiles were determined. Later on it will be shown, how the discovered resulting fabrics can be activated to become a three dimensional geometry.

the concepts presented above will be explained later in details. The names of concepts are: JOIN, SPLIT, INTEGRATION, PROTRUSION, DENSITY, FOLDING.

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join backwards

branching out

join sideways

vertical splitting

point connection

horizontal splitting

diagonal thread inserting

point connection insert, free direction

dropped stitch sleeve for solid continuous object to insert

lace openings

tension variety

material variety

2*2 ribs, parallel

5*5 ribs, parallel

protrusion

truncated protrusion

45

I_032: Catalogue of the flat knitting fabricational concepts


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join backwards

join sideways

point connection I_033: JOINING fabrication concept

04.05.01_JOINING The first typology is JOINING. The idea was to explore ways how knitting could be attached to itself. Here are three sub-divisions: The upper one shows the way how it is possible to connect the free offshoot of the knitting piece to the needle bed and merge it with the current knitting rows. It forms some sort of a non-developable loop. The middle sub-typology displays the sideways joining methods and provides us with ways to manipulate the direction of the knitting. The bottom one is about the point connections within the knitting piece. Some labelled points are brought to the needle bed and knitted in to the current rows. The result is pretty fascinating: The geometry looks pinched in the tensioned state. It can be a good tool for surface differentiation. 46


CHAPTER 04

H

H H branching out splitting

vertical splitting

horizontal splitting I_034: SPLITTING fabrication concept

04.05.02_SPLITTING The second typology is SPLITTING. It is about the ability of knitted textiles to split the material flow in the horizontal (weft) or vertical (warp) direction. The knitting technology allows to make larger gaps in certain areas in rows(coarses) and columns(wales). It is achieved through various technological operations. The upper picture displays the possibility to have branches and knit some parts out. It might lead to more complex geometries rather than just rectangular sheets. The middle one performs the vertical openings that are made with the machine, when the amount of stitches needed is applied on to a certain course. Other stitches are on “hold� and are invisible to the machine. Later there is always a possibility to knit the left part and make branches of equal length. 47


CHAPTER 04

*processual inserting

diagonal thread inserting

*processual inserting

point connection inserting in free direction

*post processual inserting dropped stitch sleeve for post inserting of another solid object I_035: INTEGRATING fabrication concept

04.05.03_INTEGRATION The following concept is about the feature of the knitting fabrication process to integrate the other element when being produced. This builds in a soft skeleton for the fabric structure and in the assembly will prevent sagging on the bigger spans. Three sub typologies were discovered: The upper one shows the full integration of the thread, but due to the specifications of the machine knitting it is possible only in diagonal directions. The middle one shows the point inserting of the thread in the free direction. Since it is not a full integration, the direction is not an issue anymore. After threads are pulled they cause the compression of the fabrics into a very compact state. This might be a great option not only for the structural stability of the large spans but also for the deassembly and packing strate-

gies. The last sub-typology assumes that the knitting piece has a prefabricated space for the solid supporting object to be inserted. In this case it is a dropped stitch tunnel that allows to insert the active bending element, that becomes a well integrated sustaining frame for the knitted textile.

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protrusion

truncated protrusion

I_036: PROTRUSION fabrication concept

04.05.04_PROTRUSION The PROTRUSION concept is about the knitting gaining the volume in the assigned areas. This creates three-dimensional convexities on the two dimensional surface with the complete two dimensional way of fabrication. Protrusions occur as the result of the lack of space in the coarse. This is why they pop out into the third dimension. This method can be suitable for the three dimensional branching out of the surface and allows us to grow out “columns from the ceiling� as well as for the three dimensional solutions for the openings in the surface (truncated protrusion).

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lace openings

various density higher density

various material

meterial 1 thickness 50%

lower density

material 2 thickness 100%

I_037: DENSITY fabrication concept with the code patterns for knitting machine

04.05.06_DENSITY The density concept is mostly about the various ways the different densities can be achieved. Three main directions were discovered. The first is controlling the amount of porous in the certain areas, some parts become more transparent some less. The second the manipulation of the tension of the thread within the system. The biggest difference can be seen when the stitches in the non-tensioned area are dropped out. However, this can be done only with the double bed knitting machine. The third option is the use of two different materials, where one is thicker than the other. This will create more transparency in the parts where the thinner threads have been used. All the samples above were programmed with the Brother KH 930 with the stitch map images displayed on the right of the photos. The

size of the image in pixels corresponds to the dimension of the piece in stitches. Each black pixel selects one needle on the needle bed. In the previous chapter the principle of the programming of knitting machines was explained in the paragraph about Binary Textiles. There you can find more detailed information about the logic of the process.

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2*2 parallel rib

5*5 parallel rib

diverse rib sections I_038: FOLDING fabrication concept

04.05.07_FOLDING The following concept is about the kinematic feature of the knitting textile to form ribs, so called folds, when the ribbing technique is applied. With this technique stitches in a certain pattern are knitted from the different sides of the work piece. The kinematic behaviour of the turned stitch creates a highlighted rib in the structure. Usually in the fashion industry this principle used for finishing edges and necklines of clothes so they can fit better, due to the ability of ribbed fabrics to stretch a lot and return back to the compressed condition.

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CHAPTER 04

MESH FORMATION WITH A CONTINUOUS ELEMENT OF UNLIMITED LENGTH

SETS OF ELEMENTS

PLAITING WITH PASSIVE AND ACTIVE SYSTEM

+

imple crochet stitch (face & reverse) fig. 39)

Plain knitting: right (fig. 43a)

Simple wrapping of a passive element with Z slant (fig. 47a)

KNITTING

Wrapped binding parallel to one of the passive systems (fig. 55a)

Encircled coiling, wrapping around adjacent elements (fig. 62a)

ACTIVATION

lain crochet stitch (fig. 40)

Plain knitting: left (fig. 43b)

Double-looped wrapping with S twist (fig. 51a)

Wrapped binding diagonal to the passive systems (fig. 55b)

Linked coiling through mesh of activ element (fig. 63a)

ouble crochet stitch (fig. 41)

Crossed knitting (face & reverse) (fig. 44a)

Interconnected looped wrapping (fig. 53)

Looped binding parallel to the passive systems (fig. 56a)

Simple looped coiling, interlocked w mesh of active element (fig. 65a)

I_039: KNITTING + ACTIVATION diagram, nessesity of the activation method for the fabric structures

ing ropes will be an obstacle for the interior circulation flow . Also As it was specified earlier, the current chapter discusses the whole tensed system is very dependend on the external structure Looped binding diagonal to the passive Coiling with clove hitches (fig. 66c) different ways can be into a three-dimenreble crochet stitch (fig. 42) knitted textiles French knitting on aactivated stick (fig. 45b) Knotted wrapping(fig.that 54) it is connected to. With the non-mobile external structure, fabric systems (fig. 56a) sional geometry. construction remains permanently fixed to the place. On the other CROCHET KNITTING WRAPPING BINDING COILING hand, there is always an option to detach the textile object from the 04.06_KNITTING + ACTIVATION = ARCHITECTURE? Together with the activation mechanism the knitted fabrics supporting structure and assemble it in a different place. It makes convert from the weak non-structural cloth to the taut elastic tensile the fabric architecture transportable, because it can be easy packed material. Activation systems can be divided into two big groups: ex- in a cardboard box and moved away. The external-integrated activator can be attributed to the ternal and additive-internal. External activators are the ones that attach to the fabric previous group. The activator is integrated into fabric construction mostly on the edge (thicker ropes or even branched out knitted nar- as an additional more strong continuous thread. The difference with row sprouts) and intend to stretch the textile into shape. This is the the first one is that it gives more substantial support on the larger most basic and traditional way to stabilize tensile fabric systems. spans of the material and prevents sagging in the middle. Additive-internal activators are called so due to the way However, it brings a lot of limitations to the design: spanned balanc- how they interact with the fabric. The process of activating fabrics

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I_040: Pro Elite Knit Sport Wear Collection, NIKE Inc., 2013

in this case is an additive process and the activator remains within the fabric system for the entire time of the structure’s existence. The additive activator compensates the weak structural properties of the fabrics themselves. Examples are: pneumatic activation (stays inflated all the time) and inserted bending elements. The benefits of this method of activation is that now the fabric structure becomes mobile and able to travel. It is not connected to the environment and stays stable with the help of the activator. Pneumatic activation is a fast and easy way for the assembly. In a real time scenario the construction can be brought to the site and simply plugged in to the air compressor. It takes a few minutes to bring the geometry into shape. The drawback to this method is that the pneumatic activator will need to stay inflated all the time the structure functions. This may lead to high energy consumption as

well to danger of collapse in the event of electricity loss. Active bending elements (GFRP rods) are another example of additive-internal activators and has its own pros and cons. The advantage lies in the ease of assembly: A bending rod can be decomposed into small segments, removed from the fabric object and transported to the new venue. The complexity is in the design stage when the tunnels for rods need to be created. The last activator is an additive-embedded activator. It is a full or partial post impregnation of fibres with an epoxy resin mixture within the system. With the permanent activation, it becomes tricky to fold the fabric into the maximum compact stage (unless it is a partial impregnation that implies folding). This requires some development for the resin application process. 53


CHAPTER 04

I_041: ACTIVATION # 01, tension activation and joining fabrication

54


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stage 1: produce continuous ribbon

stage 2: define areas of connection, can be also labeled while stage 1 in the process with another colour thread

stage 3: finish the object by connecting the first ribbon with the connection ribbon while the process goes

I_042: ACTIVATION # 01, fabrication sequence diagram

more accurate than sewing, and what is more, no additional machine is needed. The continuous additional knitted connector forms some The following prototype shows the way a object can be fab- sort of arch. The resulted object performs a serrated geometrical outricated by using the self-joining method and activated by tensioning come. Within one system it has complex double curved surfaces, it to the external frame. The fabrication process can be described as a two stage openings and a continuous flow of the material. The joining principle process: first to produce a single continuous knitted ribbon. This is results in non-manifolded surfaces and interesting spatial situations. 30 stitches wide and 300 stitches long. The length should be enough to attach it to itself again. After the ribbon is produced, the knitter casts off the last row and detaches it from the machine. Now the first stage of the fabrication is complete. The next step is to implant the areas that should be connected one on top of another onto the needle bed, Then the needle carriage will connect the individual layers by travellling along the rim. It creates the solid clean connection, way 04.06.01_TENSION ACTIVATION + SELF JOINING FABRICATION

55


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I_043: ACTIVATION# 02, tension activation and self splitting fabrication method

56


CHAPTER 04

H

H

2/3 of second interval

first interval first interval

bind off second interval

beginning of the third interval

first interval

third interval

second interval

*2

to complete the prototype connect two equal parts together

first interval I_044: ACTIVATION # 02, tfabrication sequence diagram

04.06.02_TENSION ACTIVATION + SELF SPLITTING FABRICATION

first bottom offshoot. At that moment, when the second interval is exactly the mirrored image of the first one, implant the end of the second interval offshoot back into the needle bed. At the same time bind off the root of the second interval. The next movement is to grab the offshoot of the first interval and plug it on to the machine next to the offshoot of the second interval. Now the last third interval can be fabricated. When the piece is complete, cast it off the machine and repeat the procedure all over again for the second piece. Having this done, connect them on the knitting machine. The result can be a building component and represents the developable three dimensional object that brings layers to the system and big openings for light come through.

The following prototype shows how the object can be fabricated employing the self-splitting method and activated by tensioning it to the external frame. A more detailed visual explanation can be found in the DVD attached to the booklet. The prototype object contains two equal parts connected together at the seams. Theoretically, the same but seamless result can be achieved with the double bed knitting process. The description of the fabrication process will be explained for one part: The whole piece is knitted as a sequence of “hold“ and “active knit“ functions. The diagram above shows the way it is done. First, the beginning interval, then keep knitting the right outgrowth till it reaches the correct length. Later cast on half of the row next to the knitted outgrowth and knit until this mathes the length as the The video of the process is saved on the attached DVD. 57


CHAPTER 04

I_045: ACTIVATION # 03, GFRP active bending rod activation and self integration fabrication

58


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the solid inserted object provided the steady finishing of the edge of the structure

I_046: ACTIVATION # 03, zoom in detail of bending rod inserted into fabric.

of the bending rod is, the stronger it is and will provide a less significant bending amplitude. The most crucial part in collaboration of those two systems is to find the right equilibrium between the structure of the textile and the strength of the bending supporting element. The object is fully independent and can be easily transported, either in an assembled state or packed. This example can be scaled up by increasing the span of the fabric and the thickness of the bending rod. The architectural application can be a shading canopy or summer pavilion.

04.06.03_GFRP BENDING ELEMENT + INTEGRATION FABRICATION The subsequent prototype displays the way the object can be produced using the integrating method and activated by inserting an active bending rod into the fabric. In this case, as already mentioned, the designer (or knitter) takes into consideration the path where the bending element will be inserted later. In the respective areas one stitch is dropped in order to create some sort of a tunnel where the solid object will sit in. Offshoots in the middle are later connected underneath to build the hyperbolic surface. The circular shape is achieved by keeping each 5 rows of the last 10 stitches on “hold“. The external loops are gaining rows while the inner ones have fewer rows. The circular direction of the knitting process results in a smoother distribution of forces on the fabric surface. The thickness directly effects the behaviour of the structure - the bigger diameter

The video of the process is saved on the attached DVD.

59


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I_047: ACTIVATION # 04, Full epoxy resin impregnation (fixation) after pneumatic activation and density variation fabrication process

60


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before inflation the knitted object is fixed in 4 end points, later those points become a column base

I_048: ACTIVATION # 04, detail of the inflating process.

the balloon way better than the flat consistent knitting sheet. The less dense parts are stretching more and perform convexities on the surface, while the more dense areas stretch along and become the grid structure for the geometry. Contact between the fibres and resin in more dense areas will form a stronger polymer. To scale up this system will require a look in the direction of cushion creating and inflating the ballons in between layers. This concept will be developed further in the DESIGN RESEARCH DEVELOPMENT chapter.

04.06.04_PNEUMATIC ACTIVATION + FULL RESIN IMPREGNATION + DENSITY FABRICATION CONCEPT This prototype displays the way how the three dimensional geometry can be produced by varying the density with the pneumatic activation, with the later post resin impregnation. The current process has three stages: In the first the sample with the differentiated pattern of two different densities is fabricated. For this the double bed of the knitting machine is required. Next the created piece is inflated and kept in this state while the post epoxy resin application is taking place. The piece remains inflated until the resin is completely cured and the structure can take loads. Then the inflated bubble is removed. For the inflation activation it is always better to have a highly differentiated surface because as it will take the shape of 61


CHAPTER 04

I_049: ACTIVATION # 05, Partial epoxy resin impregnation (fixation) after pneumatic activation and folding fabrication process

62


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with the further development the manual process of the resin application can be exchanged with the 6-axis industrial KUKA robot applying the resin with the syringe effector

I_050: ACTIVATION # 05, detail of the partial epoxy impregnation process on the inflated framework

04.06.05_PNEUMATIC ACTIVATION + PARTIAL RESIN IMPREGNA- ribbed knitted surface is perfectly following the shape of the pneus and “opens up“ the way it is needed. The pneus are kept in the inflated TION + FOLD FABRICATION CONCEPT state while the post epoxy resin application is taking place. For now The actual prototype demonstrates the way the three di- it is a manual process in which the resin is applied with the syringe. mensional geometry can be achieved using the fold fabrication tech- The pneus remain inflated until the resin is completely cured and the nique, activating the individual elements (ribs) with pneumatic sys- structure can support itself. Then the inflated bubbles are removed. This method may open up new horizons for foldable but self tem and fixing the inflated individual ribs with the partial post resin impregnation. In this case the partial resin impregnation requires supporting structures which do not consume any extra energy. For the geometry to have highlighted areas to impregnate. It can be ribs, scaling up, the ribs should become cushions and be filled with the folds or any other visible geometrical formations that can later be- inflatable systems (e.x inflatable tubes etc.). There are two options: to come solid supportive elements. For this prototype the long ribbed leave the inflatable in the knitted cushion - then it becomes a weather protective waterproof envelope, or to remove it after cured. ribbon is created (5*5 ribs), then it is fixed to the base in 6 points. Next, balloons are inserted underneath and later inflated with the different pressure. This way different dimensions are achieved. The 63


CHAPTER 04

{ low hierarhy of articulation of the knitting { low packing volume { tension + compression system

[

WHY KNITTING ? WHY INFLATABLE ?

] inflatable knitting?

SETS OF ELEMENTS

MESH FORMATION WITH A CONTINUOUS ELEMENT OF UNLIMITED LENGTH PLAITING WITH PASSIVE AND ACTIVE SYSTEM

Simple crochet stitch (face & reverse) (fig. 39)

Plain knitting: right (fig. 43a)

PLAITING WITH PASSIVE AND ACTIVE SYSTEM

PLAITING WITH ACTIVE SYSTEM

ADVANCED TEXTILE TECHNIQUES

Right-angledWrapped plaiting inbinding plain weave Plaiting in three directions 85) wrapping Warp twining (fig. 92a) Simple wrapping of a passive element parallel to one of the Encircled(fig. coiling, around (fig. 69) passive systems (fig. 55a) with Z slant (fig. 47a) adjacent elements (fig. 62a)

Finger weaving (fig. 135)

WEAVING

KNITTING

Six-strand braid (fig. 72a)

Plaiting in four directions (fig. 86)

Countered weft twining with discontinuous Tablet weaving with inversion of twist direction (fig. 139a)

Active-passive intertwining (fig. 80a)

Bobbin lace by intertwining (fig. 87)

Openwork tapestry with displaced warp (fig. 121)

Plain weave and drafr of it (fig. 152a-b)

Slit tapestry (fig. 122a)

Complex gauze weave (fig. 178b)

Plain crochet stitch (fig. 40)

Plain knitting: left (fig. 43b)

Double-looped wrapping with S twist (fig. 51a)

Wrapped binding diagonal to the passive systems (fig. 55b)

Double crochet stitch (fig. 41)

Crossed knitting (face & reverse) (fig. 44a)

Interconnected looped wrapping (fig. 53)

Looped binding parallel to the passive systems (fig. 56a)

Linked coiling through mesh active weftsof(fig. 116) element (fig. 63a)

Simple looped coiling, interlocked with mesh of active element (fig. 65a)

I_051: Diagram showing the potential of the usage of the inflatables as the activation Active-active intertwining with braiding (fig. 81d)

Treble crochet stitchMETHODS (fig. 42) French knitting on a stick (fig. 45b) 04.07_EVALUATION OF ACTIVATION CROCHET

Looped binding diagonal passive edge Coiling with hitchesfabric (fig. 66c) that are integrated intoto thethe ofclovethe and by this tense it. systems (fig. 56a) This a good option WRAPPING method is providing BINDING COILINGto install the object independently from the external structure. The drawback of the method is that the two-dimentional tentioning is not entirely activating all possibilities of the higly differentiated textile. Even though the post-resin impregnation experiements looked very interesting, the loop based knitting structure is not the best one concerning the compression forces. The alternative way to solve this would be an activation with multiple inflatables placed inside the knitted enclosed cushion.

Knotted wrapping(fig. 54)

KNITTING

Previosly investigated activation methods of knitted fabrics are showing diverse options for actuating the cloth into the threedimetional geometry. All of the methods are having their own advantages and disadvantages. The first one - tensioning - is the best known way to bring textiles into shape. It is energy efficient, cheap and very stable, but it will always require an additional external structure to tention to: wall, tree, frame. In addition to that, the more complex the structure - the more tension points will be required. This means an increase of the tention threads around the object and a restricted access of the object from all sides. The second group of activation is active bending GFRP rods

Macrame with squire knot (fig. 91)

64

TWO-DIRECTIONAL PLAITING

MULTI-DIRECTIONAL PLAITING

WARP

WEAVING

Tablet (fig. 137


CHAPTER 04

ACTIVATION

tension activation

tension activation with a substructure

GFRP rod tension activation

Pneumatic activation, post resin impregnation

Pneumatic activation, partial post resin impregnation

+ generic inflatable ballons

KNITTING

INFLATABLES

I_052: (top) Summary diagram of the explored activation methods. (bottom) Conclusion diagram for the inflatable activation method

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Air inflation 6 bars min.

Detail of connection a single inflatable and a pneumatic pipe

Multiple latex inflatables, 40cm diameter

Polyethilene pipe for air supply, 8mm

Pneumatic dividers FESTO 4mm allow to split the single air outlet into 32 separate outlets, 4mm thick. The whole division bundle stays outside of the knitted cushion geometry

PVC pipes, 4mm, transparent are meant to be integrated into knitting design along the stiffer cables

I_053: TOOLSET #03. Set of tools used for the air inflation of the fibrous cushions.

04.08_WHY KNITTING + PNEUMATICS? Knitting together with inflatables results in a composite compound system. The knitted cushion accomodates multiple generic inflatables, that become an inflation volume activation force, driven by the constrains of the pre-programmed fabric. The synthesis between knitting and pneumatics conceives a tension-compression system. The fabric is stretched by the force of the expanding inflatables and ballons are taking the compression force to support the structure. Apart from that, the knitting-pneumatics system has a high potential to be introduced into mobile deployable architecture. The kinematic behaviour of the inflated knitted cushion revolutionizes motile architecture, in which the problem of joints and mechanics

was always crucial. The homogeneous nature of fabrics solves the connection complication in a smooth transition of the filament flow. The knitting allows to achieve a level of control to a single stitch. This means that the hierarchy of the surface articulation differs in various scales. Contractility of both systems allows to pack and transport the cushion while it is not inflated. The thin skin populated with the multiple inflatables is a new representative for lightweight structures that is worthwhile some further research.

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I_054: David Stearn, , Inverted Ballons Sculpture, 2014

latex ballons (d= 20-40cm). The transparency of the ballons will let the light through the structure and create a complex versatile illumination of the architectural space under the inflated knitted skin. The following pneumatic network is highly embedded into the design and becomes part of it.

04.09_PNEUMATIC NETWORK, MULTIPLE INFLATABLES. For splitting the air flow several pipe dividers are used. Simultaneous inflation of the ballons is very important: because being inflated gradually and all together at the same time, the multiple ballon group is getting restricted by the fabric more evenly. Multiple ballons are less shape affecting than a single inflatable that has already got a factory pre-programmed generic shape. Another argument in favor of multiple inflatables is that they are more adjustable to the complex geometries and do not need the complex cut pattern welding which is needed for the single sheet latex surfaces. In case of damage a blasted ballon is easy to replace and does not cause the entire system to collapse. The ballons that are used in the projects are transparent 67


68


05 DESIGN RESEARCH DEVELOPMENT

69

The discovered earlier synthesis between knitted textiles and pneumatic activation will be developed further in the following chapter. The capacities of the system will be explored through a series of prototypical experiemtns and digital excersices.


CHAPTER 05

I_055: Cushion formation concept. Ability of the knitted fabric to form cavities of various volumes in the process of fabrication

05.01_CUSHION FORMATION

05.02_CUSHION FORMATION METHODS

In the subchapter 04.06.04-04.06.05 (see p. 60-63) the earlier experiments on the pneumatic activation of the fabric were described. Both set ups considered the fabric as the single layer that is raised up by the force of the expanding underneath pneu. This method would not work on the larger architectural scale. Latex sheets are confined in dimensions due to the way they are produced, as well as the knitting machines have a limited width. The alternative to a single surface knitting inflation would be an inflation of a knitted cushion, that can accomodate and keep a pneu. After the knitted skin is in a shape the pneu is resting inside.

There are several ways to fabricate a cushion: seamless, from single sheet or from multiple sheets. Seamless cushions are produced directly on the machine and allow a quite complete cavity arrangement. On the Brother KH930 knitting machine this was possible, but unfortunately quite complicated to produce and time-consuming. Because of this this method was not developed within the current master thesis research and was left for future research. Single sheet cushions are made out of a single custom made fabric sheet and later the edges are attached to each other to close the volume. In this case the whole width of the machine can be used, The process is fast, due to the fact that the whole body of the 70


CHAPTER 05

seam 01 seam seam 02 no seams multiple sheets cushion formation

single sheet cushion formation

seamless cushion formation, directly on the machine

I_056: Cushion formation types: (1) seamless, (2) single sheet, (3) multiple sheets

future cushion is produced in a single process. The multiple sheet cushions are made out of two or more flat fabric sheets attached to each other. This method is suitable for scaling up the inflatable beam in width, because the limitation of the width of the machine is overcome here. Scaling can happen endlessly, as many elements are attached to each other. The seam presence in the cushion is hard to remove due to the way the domestic knitting machine functions. Seamless cushions are possible to produce but without visible surface differentiation, so that is why this method was abandoned from the beginning of the development. More complex industrial knitting machines are theoretically capable of producing seamless large cushions with a high level of various surface differentiations and could be considered as further development tools. In the single/multiple sheets cushion the

seam becomes a part of the design and integrated into the global pattern generation.

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SURFACE MANIPULATION

INTERNAL CONNECTIVITY

TOPOLOGICAL MUTATIONS

PATTERN OUTLINE

mm

I_057: Design parameters for the pneumatically activated knitted cushions

05.03_INTRO TO BASIC MAIN PARAMETERES OF FABRIC INFLATION

05.03.01_SURFACE MANIPULATION 05.03.01.01_SURFACE RESOLUTION

The next step will be to investigate parameters of the fabric cushion pattern that determines the design of the inflated knitted skin. In the current classification we hightlight four main parameteres: SURFACE MANIPULATION, INTERNAL CONNECTIVITY, TOPOLOGICAL MUTATIONS and PATTERN OUTLINE. By varying the criteria of each parameter the diversity of design outcome can be generated.

The following cluster of parameters can be divided into two groups: surface resolution and surface manipulation. Surface resolution is the parameter when the amount of stitches is taken into consideration. Each stitch added to the geometry increases fabric’s physical dimension. As soon as we start changing the dimension of one of the fabrics of the cushion the geometry of the cushion inflation will differ. The diagram above right presents the results of the experiment that was conducted as a part of the design research in the development stage. The set up of the experiment contains a cushion that is seamlessly produced on the knitting machine with a fixed amount of stitches in each row but varying the 72


CHAPTER 05

40

40

60 50 40 30 20 10 0

10 20 30 40 50 60

Displacement of the axis 4mm

40

80

60 50 40 30 20 10 0

10 20 30 40 50 60

Displacement of the axis 43mm

40

120

60 50 40 30 20 10 0

10 20 30 40 50 60

mm

Displacement of the axis 58mm

25 stithes/row 60rows

25 stithes/row 60rows

25 stithes/row 60rows

Expansion of cavitiy

Expansion of cavitiy

Expansion of cavitiy

1:1

1:2

1:3

I_058: Expantion of the cushion under inflation depending on the surface dimension

amounts of rows for each surface. The pictures above show three different seamless cushions. Starting from the left the first cushion has an equal resolution of both surfaces: 1000 stitches in each surface. The expansion of the fabric is the same on both sides, because the fabric is stretching the same way. In the next cushions the resolution increases gradually on one side: the middle example has 1000 stitches to 2000 stitches, the right one - 1000 to 3000. The following experiment demonstrates the direct link between the surface resolution and the geometrical outcome. This principle might be useful when creating a bent geometry without density surface differentiation.

05.03.01.01_SURFACE RESOLUTION The next group of cluster SURFACE MANIPULATION is about surface density. The following subchapter discusses how the surface density differentiation is affecting the behaviour and the design of the inflated knitted skin. The knitting process on the electronic knitting machine KH 930 allows us to control the density of the fabricated mesh: porous and tight. Those two stages of the fabric differ in size of the stitches. The smaller the stitch the tighter and denser the fabric. The bigger the stitch the more the fabric expands when inflated and the more transparent it becomes. By varying the percentage of the tight zone on the fabric according to porous, we can achieve a different level of influence on the geometry. 73


CHAPTER 05 1_SURFACE

1_SURFACE

single line stiffening 1%

multiple line stiffening 3%

network of stiffened linear belts 15%

stiffened area on sides of the surface 20%

stiffened area in the middle of geometry, 20%

quater of the surface being stiffened, 25%

combination of bottom and top surface stiffening, 50%

the whole bottom surface is stiffened, 50%

I_059: The local to global impact on the geometry depending on the ration of the dence to porous areas of the cushion surface pattern

The diagram above demonstrates the range from 1% to 50% of the cushion when tight. It is clearly visible that the smaller the percentage the more local the influence. The small tight straps on the surface will mostly affect the local surface differentiation, but the global geometry of the object will stay the same. The increase of percentage of tight stitches in the geometry will be significantly visible above 25% of tightness. Normally the stiffened zones when underlying the porous ones tend to bend the geometry concave down. Later this phenomenon will be described more in details. The test prototype on the right demonstrates the whole range of possible density differentiations. It is clearly noticable that the local strap tight areas only locally effect the ballon surface. The bigger contrast in density is causing the object to bend. It is important to notice that irrespective of the number of

times the structure is inflated the geometry will stay the same. This means that the self-rearrangement of the ballons will always end up with the same fabric expansion.

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I_060: Stopmotion of the inflation of multiple balloons in a surface diffirentiated cushion

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I_061: Close up view on the fabric details

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2_INTERNAL CONNECTION

two sheet set up of fabric

point internal connector

linear internal connector

I_062: Impact of the inner connections within the cushion on the geometry

05.03.03_INTERNAL CONNECTIVITY Internal connectivity is the parameter when internal connectors are introduced into the geometry. The connectors can be a single thread that is connecting opposite cushion sides, or it can be a series of lines in a row. By varying the length of the connectors it is possible to achieve different extendability of the cushion while inflated. Basically the connectors are holding the geometry together. If we start modifying the fabric properties around the connectors, it will cause the geometry to bend, because in this case the connectors will work as hinges. The experiment that was conducted to prove the feasibility had the following set up: a custom knitted cushion with 5 different cavities in a row. Each cavitiy had a separate inflatable element in-

serted. The resolution of the cushion surface was varying from cavity to cavity. Depending on which side of the cushion was having a bigger resolution, the direction the folding was changing. As the cushion was inflated more on one side than on the other, it was pushing onto the neighbouring volume creating an extreme folding movement. (as it was described earlier on p.71) Even though this design parameter was really promising, it was not choosen for the further development of the project due to the high complexity and time costs of the fabrication.

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I_063: Stopmotion of the inflation of multiple balloons chain cushion with the different level of expansion of each volume

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rectangular pattern

parallelogram pattern

kite pattern

I_064: Relation between the matrix of the fabric sheet and the inflation outcome. Digital speculation.

05.03.04_PATTERN OUTLINE SHAPE Normally the knitted surface that comes from the machine is a continuous extrusion with fixed boundaries. This is the most efficient and the fastest way to produce knitted textiles of fixed width and unlimited length. However, there is also the possibility to create other shapes than rectangular ones. This is possible when the knitter is modifying the width of each row while the fabric is being produced. It is obviously more time-consuming, but on the other hand it is creating a custom made fabric shape without wasting any material - as is the case when rectangular fabrics are cut into the desired shape. The principle of having a custom outline fabric meshes can be also used in cushion geometries. We know that structure of knit-

ted fabric is organised by coarses and wales (rows and columns) and the elastic properties of knitted fabric derive directly from this structure. The diagram above shows the difference between three various outline patterns of the fabrics with the original verticalhorizontal stitches orientation. The first one shows no twisting while inflated. The second is starting to twist in opposite directions. And the last - twists in the same direction. This bevavior of the knitted inflated mesh is directly connected to the direction of the internal arrangement of stitches within the system. The bending plane will always be the same as the column plane. The current investigation was very promising but due to the time-consuming factor was not considered for detailed development of this master thesis project. 80


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05.03.03_ Local larger opening Feature of larger openings formation for increased light transmission through the cushion also creates the convex surface for sound reflection and acoustic performance.

I_065: Larger openings on the surface of the knitted cushion are causing the latex to expand outward from the retaining fabric volume

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Feature of integration the third element into the system (here pneumatic pipes). Air supplier pipes are traveling along the stiffer belts to the point where the inflatable should take place

I_066: Pipe integratin into the knitting system

05.03.05_PIPE INTEGRATION As mentioned earlier in the chapter about pneumatic toolset, the role of PVC-pipes is to deliver the air to the individual inflatables. With the increment of inflatable units the amount of pipes will grow as well. This means that the pipe integration into the design will be very crutial. The pipes needed for the enormous amont of air supply should become an integral part of the design and not destruct or encumber it. Fortunately the knitting technique is very flexible and allows to fabricate a special sleeves in a fabric to accomodate the pipes along the cushion surface. The image on the right demonstrates a mock-up test for the pipe integration detail. The basic principle for the detail creation is to have one

stitch in the row being opened to create a small opening where the pipe can pass through. The digital code for the machine is the series of individual pixel dots on the canvas of dense fabric. In the ditigal model for pipe detail pattern generation only the dense fabric areas are considered. Pipes located on the dense, not expanding, area of the fabric cushion are more protected from being pulled by the expanding volume of the ballons, because the dense fabric areas stay less stretched when inflated. In the pattern generation computational model the line that shows the direction of pipes flow on the cushion surface will create a flow of dots that will later become small openings for the pipes to be inserted. 82


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integrated into knitted surface PVC-pipes

Stopmotion I_067: Pipe integration of the inflation detail, of multiple knitting code balloons for the in a pipe diffirentiated integrationcushion detail

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JOINING OPTION # 01 2 parallel elements joining in SEAM

JOINING OPTION # 02 1 elements merging to another through EXTRA OPENING

JOINING OPTION # 03 3 elements are connected through ends

I_068: Joining strategies for knitted linear cushions.

05.03.06_JOINTS DETAILS The knitting has a capacity to be attached to itself. Therefore three different ways to connect design elements to each other. In the diagram on the left: the attachment option for parallel linear elements. In this case the cushion seam is used for the merging detail: the two openings of the seams of both elements are left open, so they can be reconnected. In the second of the diagram: branching method in situation when the seam location is not corresponding to the attachment position. Then the opening within the tight area of the fabric should be create to merge the attaching piece into it. The next drawing to the right demonstrates: branching of elements from two into one without varying the dimension of branch.

It means that the uniting branch stays same diameter as one of the inflowing ones. In that case two elements are merging into the single cushion. To connect all three ends of the elements the middle point of all edges are pulled into one point. The elastisity of the fabric will surely allow this without specific cut patterns. The last image on the right illustratrate similar principle as was just described, but in this situation two elements are merging into one by opening one side of each. The uniting volume can be twice big as the inflowing volumes, or different. By varying the pattern outline it is possible to achieve the contraction of the geometry.

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Brother knitting machine KH 930

endless continutity of the process

I_069: Linearity of the knitting process diagram

05.04_CONTINUITY OF THE PROCESS_ WAY TO ARTICULATED LINEARITY The way how the knitting process is accomplish certainly influences the design. Knitting machines are usually limited in width: Particular knitting machine that is used for the project development is able to produce a canvas up to 200 stitches. This width can be stretched up to 2m depending on the tension settings of the machine. Although the design is limited in width, it is absolute is lengh: it is possible to produce piece as long as there is a power to do it and there is enough filament material.

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balck - porous white - tight

The current experiement’s aim was to investigate the relation between the assigned pattern and the resulting geometry on the real knitted inflated geometry. The pre-definition of the flat initial pattern was accomplished utilizing the experience gained in previous experiements. Porous and tight areas were placed along the cushion flat unrolled geometry according to assumed bending zones.

bending area

02

01 wide surface belt

bending area

thin light stripes on the code mean that in this areas will be local densification in form of stiffening belts

03

high densification in contrary to darker zone signify the stip bending behaviour of the inflated

04

05

I_070: Knitting code for the prototype that is shown on the right

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03

01

05

04

02

I_071: Prototype to test various possibilities for a curvature formation as well as local surface differentiation

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porosity 0% (420/0) porosity 8% (420/33) porosity 24% (420/99)

porosity 47% (420/198)

porosity 24% (420/102)

porosity 47% (420/198)

porosity 49% (420/204)

porosity 36% (420/152)

porosity 56% (420/236)

I_072: DESIGN to FABRICATION sequencce, BOTTOM UP APPROACH

05.05_DESIGN APPROACH: BOTTOM UP & TOP BOTTOM After the series of empirical experiemetns were acomplished, the next step was to develop the computational model that would show a kinetic behaviour of the geometry according to the assigned surface pattern. In order to create the computational model all the experience obtained earlier was considered. The design process had two directions: bottom up and top down. Earlier empirical investigations concerning the relation between the pattern and the resulting geometry can be called as BOTTOM UP design approach: in this approach manually predefined patterns were resulting in various inflated geometries. Whereupon the consclusions about pattern-geometry relation were made and contributed directly to the TOP DOWN design

approach. The diagram above illustrates the various different digital outcomes that might be expected in case of inflating the respective knitting patterns. The main aspects influencing the geometry in this case are: porosity ration and porosity location. As explained few pages earlier: less porous stithes are concentrated together, less expansion is occuring in the region. The first row of shapes in the diagram above shows the gradient between the increasing porous area in the middle of the linear element and the increase of curvature in the respective resulted geometry. The second row of digital experiments shows the importance not only of the porous area percentage but as well as the location of the porous areas on the fabric canvas. For example, when a porous area is divided into two and distributed to opposite sides of the canvas, this will lead to the double side bend88


CHAPTER 05

stage 01: initial target curvature

stage 02: calculation of the expansion areas on the cushion linear geometry

stage 03: inflation simulation in Kangaroo

stage 04: unrolled 2d flat pattern for the knitting machine

#

g din n e le b ing s _ 01

#0

gs din n e le b ltip rsion u o 3_m ith t w #0

gs din n e b wo 2_t

I_073: DESIGN to FABRICATION sequence, TOP DOWN APPROACH

ing of the geometry in one plane. Shifting porous zones along the canvas area will produce varios more complex bendings of the geometry. The obtained curvatures were recorded. After this had been achieved, the next step was to develop a model that would have the opposite result: to produce the flat knitting pattern needed for knitting cushion that, when inflated, would perform a certain target curvature. First, the curvature of the initial target curve is evaluated. Then the areas of expansion are calculated. After this the test inflation is launched digitally. Finally, when the geometrical result is satisfactory, the flat 2d knitting pattern is being created. The diagram above shows four sequantial stages of the top down design approach. The first row shows the targeted threedimentional curves with the calculated curvature. Below this the row

with the estimated areas of expantion. After that - the digital test simulation of the inflation can be seen. The lowest row represents the unrolled flat 2d knitting code that is ready to be used to fabricate the real knitting mesh. The dark zones on the pattern express the porous expandable areas of the differentiated fabric. On the next pages there will be series of prototyping tests where the linear geometry is assigned to varios patterns and the curvature is recorded. Generally, the experiemtns proved the stable relationship between the porous areas’ distribution along the cushion linear element and the three-dimentional geometries that it creates when the multiple ballons are being inflated.

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knittitng code

textile sample

porosity/density ratio 1:8

porous pattern, 7000 stitches dense pattern, 49000 stitches

I_074: Knitting pattern of the diffirentiated cushion, porosity/density proportion is 1:8, top view photo.

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knittitng code

textile sample

porosity/density ratio 1:4

porous pattern, 14000 stitches dense pattern, 42000 stitches

I_075: Knitting pattern of the diffirentiated cushion, porosity/density proportion is 1:4, top view photo.

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I_076: Stopmotion of the inflation of multiple balloons in a diffirentiated cushion, porosity/density proportion is 1:8

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I_077: Stopmotion of the inflation of multiple balloons in a diffirentiated cushion, porosity/density proportion is 1:4.

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I_078: Stopmotion of the inflation of multiple balloons in a diffirentiated cushion, porosity/density proportion is 1:4, higher level of pattern complexity

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porous pattern, 10740 stitches dense pattern, 31260 stitches

I_079: Knitting code for the higher differentiated cushion with circular porous expansion areas. . porosity/density proportion 1:4

05.06_ BENDING BEHAVIOR STUDIES Multiple prototypes with different surface patterns were produced to record the way they behave while being inflated. In order to test a curvature of bending, the pattern was simplified into a single stripe of porous stiches in the middle of the knitting canvas. The curvature derived from the pattern: the proportion between porous and dense zones. Proportion 1:4 creates arch with radius 72cm, proportion 1:8 290cm.

To increase the complexity of the pattern differentiation the new pattern typologies were introduced. The porous areas were split into several clusters in a chess pattern along the expansion area. The new pattern arrangments create different curvature properties even with the same amount of porous stiches. This is because dense and porous areas are intertwined and tighter stiches are limiting the absoulute expansion of fabric. The dense areas are also working as surface reinforcment and local surface articulation.

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I_080: Close up view on the fabric differentiation detail

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I_081: Prototype 03, with circular porous areas

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taut points on the surface

I_082 (above): Bending behavior study, above - knitted knflated prototype, below - corresponsding graphical knitting code I_083 (left): Stopmotion of the inflation of multiple balloons in a diffirentiated cushion, higher level of pattern complexity

balck - porous white - tight major geometry bending

transition between zones

twisting

dense area

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knitting code

50 wales

50 courses

The aim of the experiment was to prove the feasibility of the higher complexity of the patterns (way less regular than previously explored).The black pixels represent the porous zones of the fabric, white - the tight ones. The sample is knitted as a squire - 50*50 stitches. The sample stretches horizontally due to the properties of the knitted fabrics. They have higher elasticity in the courses (rows).

I_084: Feasibility test of the higher level of complexity pattern fabrication. Knitting code.

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fabric sample

Feasibility test positive result: proven ability to fabricate the pre-programmed pattern of higer level complexity with precise resolution. The resulted fabric sample is performing expansion in the areas of the porous pattern as it was pre-defined in the knitting code on the left. The tension within the system is staying as it was programmed, tight stitches are not loosing their strain under the tension loads.

I_085: Feasibility test of the higher level of complexity pattern fabrication. Knitted fabric sample.

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06 DESIGN RESEARCH PROPOSAL The relation between the surface pattern distribution and the resulting behaviour of the inflated beam is explored in a way that the research development can move towards exploring design intentions. The following chapter will discuss the design opportunities that can be achieved with the developed system.

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T IA INI

L T A R G ET C U R VE

DIG

ITAL SIMULATION TT PA

ERN GENERATIO

N

TOP BOTTOM APPROACH

EVALUATION

DESIGN

DESIGN FITNESS - VOLUME HEIGHT - STRUCTURE

PREPARATION OF THE CODE FOR THE KNITTING MACHINE

B IN

A R IZ A TI O N

BOTTOM UP APPROACH

PR

E DE

FIN E D P A TT

ERN

DIG

IT AL SI M U L A TIO

N

I_086: DESIGN to FABRICATION diagram 06.01. DESIGN ELEMENT In the previous chapter the design system that was developed is a linear element. This element is able to bend in all directions according to the assigned surface pattern of the knitted cushion that holds and constrains the multiple inflatables. The inflatables are the main activation force and are constrained by the custom knitted fabric. The linear nature of the element is due to the fabrication process of knitting: unlimited extrusion in one direction. The elements can be multiplied and connected into several clusters. The connection typology between elements can create various spatial and surface situations: from separate elements to the merged wide surface, which is created when single elements are connected side by side.

06.02. DESIGN TO FABRICATION The Design to Fabrication diagram demonstrates the process from the first design to the final fabrication of the real object. In the beginning the design stage is split in two: a bottom up and a top down approach. The differences between those are in the initial input information. The bottom up process requires the pre-defined pattern, that can be inflated at a later stage. The Top Down requires a target 3d curvature. After a few iterations, when the digital simulation visualisation fullfills the design requirements, the binary pattern can be generated. At this stage of the process, the 3d mesh is unrolled into flat 2d pattern with the indication of the porous zones highlighted in black. The pixelled black-and-white image is a code that can be used by the knitting machine for the fabrication of the custom 104


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M EN T M A TERI

AL

IN G IN F L A T A

INFLATE ON SITE

ES

KNI

D ED

BL

EMB

FIL A

T TI N G M A C HI NE BRING ON SITE

KNIT+PNEU

IN YOUR BAG

DEINFLATE

USE IT

PACK

store -generic speculation about the programm (due to mobility and deploble character of performance) should have a temporary use.

made fabric piece. After the textile has been knitted, the cushion is created and a network of inflatables is embedded into the cushion. Then the knitted inflatable skin is ready to be packed and transported to the installation site. There it can be inflated and used. When not needed anymore, the structure can be deflated and installed again in the new place. The characteristics of the developeded design system are introducing it to the mobile contractile architecture with the dynamic programme. Self-assembling inflatable knitted skin can become a shelter for outdoor temporary events.

-about the concept of mobile architecture, inflated on site, easy to 105


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option # 01, 5 elements

option # 02 5 elements + 2 fabric membranes

option # 03 4 elements + several fabric membranes

option # 04 4 elements + several fabric membranes

option # 01, top view

option # 02 top view

option # 03 top view

option # 04 top view

option # 01, faรงade

option # 02 faรงade

option # 03 faรงade

option # 04 faรงade

I_087: Diagramatic catalog of the geometrical outcomes for a temporary pavilion 06.02_DESIGN OPPORTUNITIES The linearity of the knitting process and the developed system to control the geometrical behavior of the knitting opens up a certain range of the design opportunities. The continuous nature of the design element introduces various possibilities how it can be used for space creation. It was mentioned in a previous chapter that knitting is capable to attatch to itself and outspread for an unlimited distance. Multiplication of the elements, that are travelling is space, merging and branching off each other, will create a versatile space divisions: from porous lattice structures to solid rib structures. In this case the design element is a ribbon that moves in space how its textile nature prescribes.

Above, there are several design iterations of how the design element can form a pavilion architectural shape. The pavillion is the most suitable architectural typology that would demonstrate the features of the developed design & fabricational system. That is why it was choosen for the development. The main design intention was to use the system to create shading space supported by several columns having an elaborate surface differentiation and intricate light transmission. Design iterations explore various spatial situations that system would allow us: columns, walls, and lattice roof structures. The geometry grows from the ground, where the elements either form a linear section support or bundle of elements together. As elements reach the eye level of the user, they start splitting into the lattice structure to cover as much space as they can, spreading to the 106


CHAPTER 06

option # 05 5 elements + 2 fabric membranes

option # 06 6 elements + several fabric membranes

option # 07 6 elements + several fabric membranes

option # 08 6 elements + several fabric membranes

option # 05 top view

option # 06 top view

option # 07 top view

option # 08 top view

option # 05 faรงade

option # 06 faรงade

option # 07 faรงade

option # 08 faรงade

sides. The openings formed between the elements are providing the light transmission underneath the roof. For a bigger shading effect as well as for the structural stability, the openings can be optionally enclosed with the thin layer of knitted fabric. The following design iterations should be considered as an elaboration of a tripod pavilion typology. The richness of the knitted inflatable skin system allows to alter the number of columns and the typology of the geometry in general. The great advantage of the system for the design opportunities is that elements can be multiplied and this way enlarge the space. Iterations demonstrate increasing complexity from the left to the right. 107


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fabric membrane layer abstracted into the quad mesh with the higlighted edge stitches

single layer fabric membrane

porous extensible fabric stiffened fabric (tight) for fabric membrane to be attached tight property of the fabric

the nce eque ched in kwise s n i atta cloc ic jo fabr eet are r sheet l a i bou tent ic sh e po ch fabr he neigh 1m h t f e, h= n o s of ea - to t s o a i t b ge r edge sec ort e ed e supp d e thre dle, oth at el ev mid I_088: Prototype design development for demonstating the abilities of the developed system

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linear element 01

linear element 02

linear element 05

linear element 03

linear element 04

knitting code pattern 01 stitches 147, rows 1491 Lengh: 4,47 m Porosity coefficient: 0.016 Porosity: 12%

knitting code pattern 02 stitches 147, rows 1560 Lengh: 4,67 m Porosity coefficient: 0.024 Porosity: 14%

knitting code pattern 05 stitches 147, rows 913 Lengh: 2,73 m Porosity coefficient: 0.024 Porosity: 21%

knitting code pattern 03 stitches 147, rows 1560 Lengh: 4,67 m Porosity coefficient: 0.024 Porosity: 14%

knitting code pattern 04 stitches 147, rows 1491 Lengh: 4,47 m Porosity coefficient: 0.016 Porosity: 12%

porous: stiff 1500, rest len 0.04 tight: stiff 1300, rest len 0.02 mesh pressure: 12000 Inflatables units: 34

porous: stiff 1500, rest len 0.04 tight: stiff 1300, rest len 0.02 mesh pressure: 12000 Inflatables units: 36

porous: stiff 1500, rest len 0.04 tight: stiff 1300, rest len 0.02 mesh pressure: 12000 Inflatables units: 21

porous: stiff 1500, rest len 0.04 tight: stiff 1300, rest len 0.02 mesh pressure: 12000 Inflatables units: 36

porous: stiff 1500, rest len 0.04 tight: stiff 1300, rest len 0.02 mesh pressure: 12000 Inflatables units: 34

I_089: Knitting codes for the prototype elements

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single layer stiffened zone fabric for fabric membrane attachment

tight

porous

I_090: Top view of the prototype proposal

06.03_PHYSICAL PROTOTYPE The purpose of the prototype is to demonstrate potentials of the system on a 1:1 scale within the built fragment. The prototype can be a part of a larger system if the number of elements are multiplied. The design of the prototype is following the intentions to show the potentials of the system: - capacity of the system to perform different three-dimentional bendings while activated with multiple inflated ballons, - global/local pattern differentiation -various stages of transparency: on the surface and geometry level - ability of knitting to attach to itself -integration of pneumatic pipes network into knit.

The design process was accomplished as it was shown on the diagram two pages ago (chapter 06.02, Design to Fabrication Sequence). The initial input for the design was five, three-dimentional splines that were proportionate to the desired spatial arrangement of the future prototype. Those lines set the direction of the elements as well as the dynamics of the model. The next step was the calculation of the curvature. The computational model that was developed within the project development stage deducted the extrinsic curvature: compute the amount by which the lines deviate from being flat and straight. Then the ancillary pipe mesh geomemtry was created. The next step was to calculate the locations of the expandable areas for the knit. Those that lay on the concave down area of the ancillary pipes later became assigned properties of the porous fabric pattern. 110


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PVC-pipes direction, pipes are following the fabric differentiation and located only on the tight zone

High resolution knitting code, quad mesh 144*184 pixelated image map ready to use by knitting machine

Low resolution knitting map with the porous /tight area differentiation Black: porous fabric property Red: stiffened fabric attachment area, single fabric layer to be attached White: tight fabric property

Low resolution knitting map, quad mesh 18*23

I_091: Explosion diagram of the low resolution simulation knitting map related to the high resolution knitting code

The rest of the mesh was assigned the tight fabric characteristics (stiffness, rest length etc.) After each quad of the mesh of the geometry got assigned to the corresponding parameters, the geometry was ready for the test digital inflation. The digital inflation provided the approximate visualisation of the future pneumatically activated knitted skin. The precision of the simulation was enough for drawing the conclusions. If the evaluation had been positive, the flat 2D knitting pattern was created. This pattern is a planar mesh equal to the inflated one. It has a complete equal arrangement of the quads and the corresponding parameters as the three-dimentional one. For the computational calculations it is always faster and more efficient to use a reduced resolution of a testing mesh. In our case the resolution of the mesh was reduced by 8 times. After the 2D low resolution mesh had been produced, the next step was to equalize

it to the real resolution mesh that would be used to create on 1:1 scale pattern for the knitting machine. The local pattern definition and pipe detail integration layer can be applied only on the high resolution mesh due to the scale of the pattern. For example: each pipe integration stitch is a single mesh face on the high resolution mesh canvas. For the pipe integration detail, the initial data is a line flow on the pattern. By crossing the tight mesh - the flow line assigned hightlights the single mesh face selection with predefined regularity. In order to prevent extreme unnessesary porous mesh expansion, the locally distributed narrow straps are covering the following zones and are creating interesting surface articulation at the same time. Due to the time and financial constrains - the design of prototype proposal was reduced to 3 supporting elements and 1 mem111


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2,4 m 2,1 m

I_092: Side facade view on the prototype

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2,4 m

2m

I_093: Front vide on the prototype

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#02

#01

#05

I_094: Knitted preprogrammed textiles corresponding to the initial knitting code on the right

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black pixels - tight fabric,white - porous, line of dots - openings for the pipes to integrate to fabric, black row above line of dots - technical additition to the code to complete knitting on the machine

#02

#01

#05 115


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I_095: View on the fabricated prototype from the top

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I_096: Perspective view on the fabricated prototype

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07 DISCUSSION

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I_097: Lucie McRae, Bart Hess, Evolution Art Performance, 2014

07_DISCUSSION The aim of the project was to explore knitting manufacturing techniques in order to fabricate differentiated textiles and discover way they could be activated for creating architectural space. On the first stage of the project development, the existing textile manufacturing techniques were explored and sorted into a catalogue according to the fabrication process type. The knitting technique was selected as the domain because of the properties of the obtained textile outcomes as well as due to the particular fabrication features. Later we moved to the investigation of the various activation methods. Several small scale prototypes demostrated different options of how the fabrics can be held in shape. Consequently, the evalution conclusions were made and the

particular activation method was selected for further project development. In the project development stage the research was focussed on investigating the flat knitting technique methods in synthesis with pneumatic activation. Multiple sets of experiments led us to conclude the range of knitting techniques that were suitable for inflatable activation. After the porosity and density concept was discovered as the most promising one, the development moved towards the exploration of the kinetic capacities of the knitted cushions when different porosity ratio is applied. Cushions had various layouts of porous/ dense areas and performed according three-dimentional movements in space. The consistency of performances allowed us to arrive at a bottom up approach design conclusion and correlate certain pattern 120


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I_098: Furl: Soft Pneumatic Pavilion. Interactive Architecture Lab, by Bijing Zhang & Francois Mangion, UCL, London.

layouts to a responsive 3D inflated geometry. Experiments were conducted on the digital and physical level. The process of the knitting and the characteristics of the developed fibrous-pneumatic system introduced the design element. The principle design element is a linear cushion unit with a certain expansion pattern being assigned to the fabric surface. While activated with multiple latex inflatables, it performs three-dimentional bendings showing an intricate local surface differentiation. In the next step the design possibilities were explored. As the result - The Design Catalog Opportunities were created. The range of possibilities merged into one consolidated proposal for the final prototype, that was developed in detail. The recommendations for further research development would be to look in the direction of multiple kinematic stages of the

system. While inflated, the architecture could go through several states. Another conceivable branch for the development also would be an elaboration of the soft robotics topic addressed in the previous research of this project. The potential development of the system from static inflatable skin to mobile dynamic space would bring a big contribution into responsive, deployable architecture.

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08 OUTLOOK

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I_100: Outlook of the future development of the system into the larger scale architectural outcome

08_OUTLOOK The design system developed within this master thesis project consists of highly organized filament structures activated by using pneumatic force. The ability to differentiate shapes and reach a precise level of surface property control leads us to new standarts of production. Two-dimentional, computer controlled fabrication allows to produce large three-dimentional pieces. The design target user input allows to directly calculate the code data for the machine and to be ready to start fabrication immidiately. The user oriented design process and the availability of the fabrication tool to the wide audience makes the system even more cost efficient. There are no costs for heavy equipment.

The potential of the fabrication tools enabled us to produce endless linear fabrics and to make the system definitely scalable. The manufacture of the fabric element can continue as long as there is a filament being attached. Scalability of the system allows us to rethink the application of fabrics for architecture. The knitted inflated outdoor pavilion for events can be not far away future. The high level of surface articulation admits the control of the global geometry’s behavior while inflated, as well as the surface articulation for the transparency and the light transmission. Differentiated densities can become even and non-even spreading openings. The highly intricate nature of the knit will make the architecture look the way different than the known pneumatic architecture precedents. 124


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I_101: Outlook of the future development of the system into the larger scale architectural outcome, close up view

The ability of the generated fabrics to integrate an additional supply system turns it into a pneumatic network which is characterized by the integrated joint detail. The contractile nature of the knitted fabrics and pneumatics makes them a good combination: they both can easily be folded and packed into a small volume and transported. The air activation introduced a lightweight property to the system: light to assemble, light to transport, light to store. The synthesis of the air and textile filament is an ecological combination of materials, and definitely worth a consideration. The kinematic capacity of the filament structures activated by air could be a new paradigm in moveable or industrial design. The possibilities of the developed design system are endless: there are great amount of applications how knit and pneumatics

can be used in combination for architectural application.

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09 ACKNOWLEDGEMENT

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I_102: Emily Scoones, ITECH Master Student and a good friend 128


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09_ACKNOWLEDGEMENTS I am very thankful to: my supervisors Marshall Prado, Moritz Dörstelmann, professor A.Menges, Ansis Sinke and Olga Kalina for enormous support and help, Julian Höll, Paul Poinet, Emily Scoones, Maria Yablonina, Matthias Heilmreich, Georgi Kazlachev, Alberto Lago. my mother Luidmila Baranovskaya, Conrad Elektronikgeschäft, toom Baumarkt, ebay.de, DHL delivery, Andreas Mueller AYAB Andreas Fritsch onlineverbinder.de, Glad to work in a perfect environment.

I_099: ITECH logo knitted cloth, produced on Brother KH-930 129


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10 BIBLIOGRAPHY

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I_103: K2 Universitaet Stuttgart, photo by Jogi Hild, Heinle, Wischer und Partner Freie Architekten, 2009

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10_BIBLIOGRAPHY 1. Textile Tectonics, An Interview with Lars Spuybroek, AD Architectural Design, Vol 76, Issue 6, p.52-59, 2006 2. Architecture + Textiles = Architextiles, Mark Garcia, AD Architectural Design, Vol 76, Issue 6, 2006 3. Material Design: Informing Architecture by Materiality, Thomas Schröpfer, Basel, 2011 4. Classification of Textile Techniques, AnneMarie Seiler-Baldinger, Ahmedbad, India, 1979 5. Textile Architecture, Sylvia Krüger, Basel, 2012 6. Knitting technology, A comprehensive Handbook and Practical Quide, David Spencer, England, 2001 7. Wirkerei und Strickerei : Technologien, Bindungen, Produktionsbeispiele / Marcus Oliver Weber; Klaus-Peter Weber, 2014 8. Classification of Textile Techniques, Annemarie Seiler-Baldinger, Ahmedabad, India, 1979 9. Handbook of technical textiles, A R Horrocks, Textile Institute of England, Cambridge, 2000 10. “Otherworldliness“, The Pull of Black Velvet, Latex, Tights, Quilts, Tablecloths and Flocks. Will Alsop, AD Architectural Design, Vol 76, Issue 6, p.36-41, 2006 11. Textildesign Stricken: Inspirationen aus der Natur. Francoise Tellier-Laumangue, Haupt, 2007 12. https://en.wikipedia.org/wiki/History_of_knitting 13. http://cita.karch.dk/Menu/Research+Projects/ Behaving+Architectures/Cad+Cam+Knitting+(2010) - The Listener Project, Mette Ramsgaard Thomsen. 14. https://en.wikipedia.org/wiki/Mary_Walker_Phillips 15. http://jennysabin.com/?p=684 - Jenny Sabin 16. http://icd.uni-stuttgart.de/?p=7636 - Sean Ahlquist 17. http://materiability.com/animated-textiles/ - Manuel Kretzel & Ivana Damjanovic, Animated Textiles 18. http://www.designboom.com/design/nike-free-flyknit-runningshoes/ - Nike Flyknit Shoes 19. http://www.sca.org/ti/articles/2008/issue165/MedievalKnitting.pdf - history of knitting 20. http://www.nytimes.com/2007/11/20/arts/20phillips. html?pagewanted=print 21. http://smartgeometry.org/index.php?option=com_content&view =article&id=225&Itemid=151

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