Bridging digitally design&fabrication_EN

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[index]

0.[introduction]

pgs.

2-10

1.[Design Operators]

pgs.

8-13

1.1.Definition:Design Operators 1.2.Traditional design operators 1.3.Computational processes and operators 1.4.Types of computational processes 1.5.Documentation of Operators 1.6.Rapid prototyping and fabrication operators

4.[Digital Design Fabrication]

pgs.

14-19

2.[Digital Design]

6.[Bibliography]

pgs.

68-69

2.1.Definition: Digital Design 2.2.Frame of reference: History of disassociation 2.3.Digital continuum 2.4.Digital Bridging

pgs.

32-39

4.1.DDF: introduction of the digital design fabrication term 4.2.Design models: Design information models .Building Information Models (BIM) 4.3.Component design 4.4.Mass customization vs mass production 4.5.The parameter of scale/ Scale-ability Construction description

5.[Case studies]

3.[Digital Fabrication]

3.1. Definition: Digital Fabrication 3.2.From analogue to digital 3.3.From digital to analogue 3.4.Two dimensional fabrication 3.5.Subtractive fabrication 3.6.Additive fabrication 3.7.Formative fabrication 3.8.Assembly

pgs.

20-31

6.[Summary]

pgs.

64-67

6.1.Conclusions 6.2.Experiment

pgs.

36-59

5.1.Rapid prototyping and fabrication operator, Dritsas S. 5.2.Tesselion, Philadelphia University Architecture/Marc Fornes, Adrienne Yancone/ 5.3.Chesa futura/ St. Moritz/ Switzerland/ Hugh Whitehead/ Foster and associates

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0.[introduction]

«We are facing a very important moment of transition, and because of that transition, we are at the same timefacing a crisis. The industrial society is being replaced by an information society, and that transition is changing completely the rules of the game-of all games, including those of architecture», notes Antonino Saggio (Kolarevic B., 2003)

In the past few years, a new construction process has been integrated in many architectural projects. This process is supported by the integration of digital production machines in the building industry. The use of similar technologies has been common practice for many years in other construction areas, such as aeronautics. The main reason for the delay of their adaptation in architecture has been, according to W. Mitchell (Kolarevic B, 2003), the contribution of many different elements in architectural production, typically with clashing interests. Nevertheless, architecture evolved to assimilate these digital production machines and one of the first building applications is the world renowned Guggenheim museum in Bilbao (image 01). In order to better comprehend the architectural implementation of this new reality, it is necessary to study digital design and the context in which it evolved. More specifically, we study the development of computer environments that constitute the basis for every digital design software.

Although digital design is not a new topic in architectural discourse, many of its most important characteristics and extensions still remain untouched. The scope of this paper is to examine the reconnection of design and construction through the introduction of digital production machines in the building process.

It is possible to connect the isolated practices of architect, engineer and builder under the umbrella of a cooperative work frame. This is made possible because all the contributors of a project can now work on a 3D digital project model that contains construction information even from the very early design stages. This possibility to manage both the design as well as the construction information through digital media supports a new design process. This process is started and developed by the architect, enriched by the engineer and transmitted to the builder through the exchange and update only of digital files. It is obvious that in this process the “design of the design” becomes the-

image 01: Structural scheme of the Guggenheim Museum in Bilbao and photo from the construction phase (1997). Photo from the buidling of Watercube in Beijing (2007).

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most important part of the project. In this context, a unique opportunity appears to redefine the role of the architect in relation to construction and to establish him/her as the “information manager,” a contemporary version of the chiefmason.

We aim to illustrate how the introduction of digital fabrication in architecture is the missing piece that completes the puzzle of a consistent and coherent digital process, from design to construction. Furthermore, the paper will attempt to cast a light on the vague and unknown, for many people, area of digital design and digital production. At the same time, information will be provided on the available technologies to help those who have an interest in this field.

For that reason, this paper covers not only the theoretical background that supports digital design but also presents the available technologies on digital production. The material is split in four chapters. In the first three, the theoretical background is presented: first design operators are analytically described, then the concept of digital design is analyzed, and finally digital production is explored. The last

chapter discusses the concept of DDF and presents three examples/implementations.

Last but not least, this paper, is the first attempt to introduce in the greek reality a handbook outlining the principles of digital fabrication as well as describing a series of technologies and terms. Such Bibliography was not existing up until the completion of this dissertation.

image 02: Operating CNC machines (laser cutting, 5 axis milling, laser cut panel, 6 axis robotic milling)

image 03: a) 3d scanning of a scaled model b) translation of the point cloud in a digital model , c) 3d printed physical model

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1.[Design operators]

1.1.Definition: Design Operators Operators are defined as the mechanisms that offer their users the capability to control a process through different sources. William Mitchell (Mitchell, W.J, 1990) defines operators as tools/functions that assess a new design situation. In other words, an operator is a process that takes as input a specific design situation and outputs a new one. (image 04). Design operators are tools based on digital processes that give designers the capability to reproduce and evaluate their ideas based on the specific medium (Dritsas S., 2004).

1.2.Traditional design operators

of the new situation. Nevertheless, the functions of these operators are still in use. For that reason CAD applications have introduced commands of copying Design operators are not new in architectural offsetting that perform the function of parallel drawdesign. Architects have always been using them in ing of straight or curved lines and surfaces. every phase of design. Nowadays, though, a change In this context, the attribute of the T-square design is observed. The attributes of “traditional” design medium has been redefined not only as far as the operators are re-evaluated, due to the introduction of operator is concerned, which has been transformed computers, and are replaced by new ones. from a tool to a command, but also in terms of its Traditional design operators comprise on the one function that now refers not only to one but to many hand a group of physical tools such as pencil and geometrical objects. paper, ruler, design compass and navigational Furthermore, computer as a design environment compass, and on the other hand a group of abstract provides an ideal setting for the creation of new fabrications such as axis, grid and diagram. In a design operators, while at the same time gives place computer environment, such as Computer Aided De- for an interesting discussion around this topic. As sign (C.A.D.), traditional operators are either of less a result new design operators can be created that importance or are redefined in order to adjust to the we could not even imagine in the traditional design requirements of the new environment. Design opera- setting. For example, geometric surfaces of high tors that maintain strong bonds with the attributes complexity and accuracy were unfeasible before the of their analogue medium, which has now changed, development of the opportunity to process surslowly become obsolete. The limited use of geomet- faces with digital design media. The conception and rical tools such as the T-square, which used to be a representation in space of such surfaces was either basic design tool for every designer but nowadays is impossible, or extremely taxing. Today, however, the scarcely met in architectural schools, is an example use of a computer allows us to create a design op-

image 04: traditional-analogue (ruler, compass, rapidograph) and contemporary-digital (CAD) design operators

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erator that can analyze surfaces of high complexity. It becomes obvious that the innovation of “algorithms” that was introduced by the use of computer design processes led to an ever increasing gap between designer and design, as parts of a process with more and more undetermined operators.

digitally by the translation of the paper design surface onto the computer screen design surface.

The introduction of digital tools in design, from that point on, constituted a decision based primarily on economic factors, such as optimization of production circles and standardization of communication, rather than aesthetic and stylistic ones. Time compression of design was not immediately achieved because, while CAD applications facilitated many processes, 1.3.Computational processes and operators at the same time their use demanded the development of specialized computer training by their users.

These fundamental problems were quickly surpassed An important thing to consider with regards to as the number of computers augmented rapidly, their computation procedures, which are typically in the cost was drastically reduced and they became availbackground, is the fact that they actually precede able and affordable to the masses. Knowledge on the electronic computer. Computation is the transCAD applications was accumulated and became acformation of an input to an output. Computation may cessible. The initial use of these applications, though, be performed by people with pencil and paper, with could be characterized as transitional and mimic, electronic devices, with analogue and digital combecause it only replaced through copying, existing puters (Copeland, 2000). Computations performed and established design attitudes without adding with an electronic computer can be described as dis- something new. These characteristics, of course, alcrete and symbolic. Their attributes were formulated ways accompany the early phase of medium change,

by Alan Turing in 1936 (Dritsas S., 2004) as such “analogues” constitute the mental tools that Computation and design are intricately related since allow the establishment of knowledge bridges. the early steps of development of the electronic computer. However, since a historic retrospection As in most cases after the introduction of new exceeds the scope of this paper, their relationship technologies, the transitional stage is followed by a will be viewed under the light of two of their basic phase of acceptance and identity determination. characteristics: time compression and expansion of Progressively, the tool - i.e. the computational representation capabilities. process - started to shape its identity and to es Early computer applications can be traced in the tablish alternative work models, beyond those of fields of art and science, not in architecture, and “blind” copy-pasting of existing ones. One now had are characterized by an experimental nature. Due to the opportunity of spending more time in designing technical restrictions of that time, early experiments the object through the specific medium and at the were limited to specific applications. In the field of same time appreciating and evaluating the mediums’ architecture, the innovative work of Ivan Sutherland unique attributes. The emergence and establishment in the sixties set new horizons and expectations. His of digital design identity was also assisted by the application “Sketchpad” (image 05) introduced a gradual expansion of the capabilities of geometrical new way of interaction between man and machine: tools, which in turn allowed users to quickly make an invention that set the foundation for the use of and evaluate local changes and adjustments. Based computers in design (Pantazi M, 2006). It is imporon these capabilities, designers could expand the tant to state here that the nature of this development boundaries of their creative thinking. has been and continues to be two-fold: continuous, Another step in the establishment of computational as well as intermittent. Thus, although initial explora- processes in design was the attempt of transition in tions in this area were restricted by the available me- terms of flexibility from the local to the global level, dia, the theoretical developments were outstanding. with the introduction of parametric techniques to The most popular applications we use today were handle geometry. An interesting observation is the first created at those early stages of computer devel- fact that although these technologies had development. Nevertheless, the adaptation of these new oped from the early stages, their acceptance always mechanisms in design was not immediate. Designers lagged behind their development. In this way, design were coming indirectly in touch with computation turned towards the logic of process after having through CAD applications. The first tools replaced been specifically and accurately codified, using a the existing pencil and paper practices, primarily variety of approaches based on rules, restrictions, in the documentation of the design product. CAD and relationships. Thus became feasible the ideally systems of previous decades were allowing not only multiple repetition of the design action, provoked the quick reproduction of construction drawings and either by special or generic alterations. As a result, their details, but also facilitated the processes of cor- the word “process” became one of the most attracrection and adaptation to new data (Dritsas S., 2004). tive and popular words in architectural discourse The This change of medium radically affected the means emerging advantages of computational design . of design representation, which was now happening

processes derive from their ability to produce a wide range of solutions, ideally infinite, where design could become an act of selection.  The achieved time compression was cumulatively beneficial since it actually expanded the initial phase of design as a thought experiment, as well as the subsequent phases of optimization and finalization. While the relationship between the time compression offered by computational processes and the larger degree of mental experimentation on design may initially sound tentative, the fact remains that by allowing for greater “free� time, the possibility arose to obtain more and improved design solutions. At the same time, the expansion of the representation means forced us to revisit traditional design media and introduced new pathways of design

image 05: Ivan Sutherland introduces the Sketchpad

thinking. This shift in the representation methods contributed mostly qualitatively on design, since it placed under scrutiny both our traditional perception tools, as well as our ability to construct new ones.

image 06: the code of a design operator that works within the environment of 3d program (RVB script in Rhino).

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1.4.Types of computational processes

 According to S. Dritsas, computational processes can be categorized based on three basic characteristics: a) Complexity.Complexity deals with the fact that inside restricted systems, even when the variables are well known, unpredicted behaviors occurs (Edmonds, 1996). Complexity in a process could be either qualitative or quantitative. b) Accessibility has to do with the degree of control over the complexity of a process. Accessibility is similarly into theoretical or technical. c) Compatibility follows the idea of accessibility.

When accessibility is no longer an obstacle, then the process is considered transparent. The process is combined with other ones and constitutes common ground, in a way that it no longer stands out compared to a design, for example, intention.

1.5.Documentation of Operators  Design operators began as an experiment towards

the creation of mechanisms aiming at complexity and increased accessibility. The intention was to accomplish mechanisms of the maximum possible compatibility. The existence of such mechanisms is not a new condition in design. They constitute an attempt to take advantage of the computational possibilities offered by digital technologies and are based on the ability of these technologies to deal with the resulting complexity (Dritsas S., 2004). More specifically, design operators that are based on computational processes are personal design sub-processes that allow the possibility of greater design control.

Depending on the design domain they focus on, different kind of operators appear, such as environment information operators, global generative operators, rapid prototyping and fabrication operators, environmental sensitive operators.

1.6.Rapid prototyping&fabrication operators In this paper, rapid prototyping and fabrication operators will be examined under the light of digital design and production. These operators are the main tools of digital design and offer new design possibilities. This comes as a result of their computational capability and their personalization ability, while in relation with the available technology, they provide

image 07: visaul representation of the parameters affecting the algorithm for the production of a sheet metal table. (Clemens Weisshaar, Reed Kram).

an immediate connection between design and construction.

They are based on the development of microapplications through programming, known widely as scripting. This type of programming holds the higher degree of atraction between programming languages(images 07,08). The terms high and low describe the distance between code and machine.

In other words, a programming language of high degree must be transformed many times up until it executable from a CNC machine (Dritsas S., 2004).

The text-based code that the programmer writes is introduced into the programming environment (application programming interface) of an application and then, through some transformations (p-code, native code), ends up on the level where it is executable by the code of some CAM machine (machine-code, gcode). Therefore, scripting exists between an existing software environment, a CAD application for example, and its programming interface (the programming language of the specific application), and describes a way of using particular tools of the specific application based on a code and not based on the graphic interface of the application.

The high degree of abstraction that characterizes scripting allow users, with limited experience in programming, to have access to the structure of the

application they have been working on, and to be able to quickly alter some of its functions. In a way, it allows users to reproduce their own personal tools. A typical CAD environment usually offers a great range of tools that the user does not have to create from scratch. Simultaneously, the time needed to adapt to this rather curious way of designing is relatively little if one considers that most of the commands the user has to “adapt” at his/her own will correspond to commands that the application offers in a graphical way with which most of the users are already familiar.

New design and production processes induced tremendous changes in building geometry and provided unprecedented possibilities to the architects to get back/recapture the supervision of construction they once had. By unifying design, analysis, construction and assembly of buildings with the aid of digital technologies architects and engineers have to redefine the relation between design study and design implementation.

Furthermore, they have to redefine the term “chiefmason,” under the light of a common digital data basis, as their practices could now be unified bridging, thus, “the gap between design and production, which arose when architects started to make drawings,” (Mitchell J, McCullough, 1995) .

image 08: translation of the algorithm into code.

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2.[Digital design]

“This new found ability to generate construction information directly from design information and not the complex curving forms, is what defines the most profound aspect of much of the contemporary architecture. The close relationship that once existed between architecture and construction (what was once the very nature of architectural practice) could potentially reemerge as an unintended but fortunate outcome of the digital processes of production” Branko Kolarevic (Kolarevic B., 2003)

2.1.Definition: Digital Design New design and production processes induced tremendous changes in building geometry and provided unprecedented possibilities to the architects to get back/recapture the supervision of construction they once had. By unifying design, analysis, construction and assembly of buildings with the aid of digital technologies architects and engineers have to redefine the relation between design study and construction.

they included other craftsmen in the process, a fact that made the production process even more complex. The tradition, though, of the chief-masons did not survive the socio-politic changes of the Renaissance. Leon Battista Alberti first mentions that architecture differs from construction, setting apart architects and artists from chief-masons and craftsmen due to their intellectual education.

Furthermore, they have to redefine the term “chiefmason,” as under the light of a common digital data basis, their practices could now be unified bridging, thus, “the gap between design and production, which arose when architects started to make drawings,” as Mitchell και McCullough (Mitchell J, McCullough, 1995) noticed.

Nevertheless, architecture started to separate from construction towards the end of Renaissance, by one of the most brilliant inventions of the period, that of perspective drawing. However, the introduction of perspective and drafting drawings, as media of communicating the construction information created a gap between architect and craftsman. Craftsmen, so far, were used to oral communication and to the The term digital design has taken different interpreconstant presence of the chief-mason and thus tations and during time. In architecture is, usually, could not understand the new way of communication connected with representation and manipulation through drawings. Lastly, these new drawings gave of complex forms and spaces. Nevertheless, the the architects the opportunity to approach construcconcept of unique digital design processes that differ tion without having immediate contact with the buildfrom traditional analogue ways of designing, mainly ing site. alludes a way of design exclusively embedded in a computer environment.

The division between architect and chief-mason For centuries, architects and chief-masons were one enforced the need of communicating the information thing. The knowledge of construction techniques through one specific medium, that of drawing (plans, was connected with architectural production, while facades, sections, two dimensional representations, the creation of an architectural form demanded firstly perspective drawings), so as all the people involved the creation of its technique of construction. Design in construction could communicate, given that the information was also construction information – the direct contact between them was now lost. one implied the other.

Towards the end of the 19th many architectural firms, such as the well known McKim, Mead and Whited, wanted to have full control of the construction. For that reason they produced a huge number of draw2.2.Frame of reference: ings of the building as well as construction detail drawings, while they were deciding on every detail of History of disassociation the building, for the quality of the materials and work and lastly for the payment of the constructors (KoChief-masons,” from the masons of ancient Greece larevic B., 2003). Thus, they were creating more and until the masons of the Middle ages, were responmore layers between them and the building site. As sible for all phases of a building creation, from design Howard Davis mentions “as the system was expandstudies until construction. Their ruling position in ing, the role of the general constructor became more building industry was the result of their ability to deal, powerful while the relationship between architect and mostly, with stone. As time went by, the introduction craftsmen was diminishing.” of new materials and the development of building industry made the supervision of a whole building by The 20th century brought even more complexity in architects/chief-masons impossible. For that reason, design and construction, as new materials, technolo-

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gies and processes were introduced in building construction. The increased complexity was accompanied by an augmented expertise and the appearance of technical consultants of different kind. While the complexity of the buildings was increasing and the time needed for design was diminishing, architects were searching ways to form security belts to avoid too much responsibility on the building site. This fact progressively removed architects’ right on making construction decisions and thus the distance between them became even bigger. The contract issued from American Institute of Architects, necessary in order to obtain a building permit, mentions that “the architect has no control, nor is responsible for the construction means, ways and methods” (Kolarevic, 2003).

puts/data and representations of a design proposal as descriptions of internal functions of the construction building system(images 09-12).

Current digital design definitions still differ between design environments and environments of construction data. The introduction of the concepts of rapid prototyping and digital fabrication tend to diminish these differences in digital design and emphasize the design continuum, materialization and construction.

2.3.Digital continuum

2.4.Digital Bridging

Digital design method could be described as a structured relationship between information and ways of representation that supports design in computer environments. This relationship could run materialization data/inputs or even computational data/inputs. Parametric design programs, such as CATIA,Solidworks,Alpha Cam,Revit, could offer in-

It is under discussion whereas drawing production arose in building reality due to the necessity of dividing design from construction or if its introduction contributed to the realization of this division. Today’s heritage, though, is the law context in which everyone that deals with construction has to accept. A heritage that often demands a great number of drawings, even

for a project of medium size and complexity. This may seem excessive in the context of Greek reality, where an important discrepancy is been observed between the design studies/projects that follow the law and the realization of them. Nevertheless, this strict law context is the construction reality followed in the majority of the states of the European Union and the United States of America.

The allocation and fragmentation of responsibilities is what makes the production of shop drawings necessary. In other areas, such as naval engineering, designer and constructor often constitute a unity in the face of law. As a result, there is little, if any, need for drawings. Many shipyards have diminish their drawing production working directly with one accessible to everyone three-dimensional model, from design until construction. Digital geometric inputs are exported directly from this three-dimensional model and are introduced to automated construction and assembly machines.

Naval engineering and other practices such as aeronautics directly adopted these new technologies and adjusted their construction line to the new conditions, while something similar did not happen in architec-

ture. This was the result, on the one hand of the fact that designer and constructor were most of the times a single legal entity and on the other hand because these practices did not have to deal with a structure enacted by the law as building construction reality, which is sluggish and relatively negative to drastic changes because it involves clashing interests.

Bernhard Franken informs us that Boeing integrate this production method because it could reduce the production costs 20%. Obviously, apart from the reasons mentioned above, the economic factor was one of the main ones, if not the most important, for the introduction of these technologies.

Thankfully, digital reality that recomposed from scratches many construction fields, touched architecture as well. Many architects immediately responded to this reality and took advantage of the possibilities digital design provided. They could, now, reproduce and provide digital construction data to constructor and construction companies, which were now able to process and then propose accurate material estimations and production costs. In these new processes of direct information exchange digital design information is transformed in construction information and vice

image 09: restricting parameters for the design of Surface Bridge (Singapore) and mean curvature analysis diagrams (IJP corporation) images 10-12: 3-d representations and models of the bridge (IJP Corporation)

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versa without the in-between time-consuming and susceptible to mistakes stages of drawing production.

The three dimensional model that is being created and controlled by the designer becomes the only source of design and construction information. It embodies all the necessary information for the construction of a building. Layers of information are added, enriched and subtracted during the whole design and construction process from architects, engineers and constructors, which are following a predefined work plan. They are, thus, working in cooperation on one digital model from the early design phases.

Such a production model presuppose the unification of all design, analysis, representation and construction tools in a coherent digital environment that could offer information for any qualitative or quantitative element, not only for the design but also for the construction phase. What was at stake from the first appearance of CAD applications, three decades ago, was how the created informational model could facilitate a project in all stages, from the idea, through design (image 13b,c,d), to construction and completion of the building, while at the same time could provide a digital environment that will allow an easy and without obstacles communication between the people participating in the project.

In any case, such a working model diminishes draing production and if applied in every project stage, it is estimated that there will be a benefit of 28-40% in time construction.(Kolarevic, 2004) This fact, though, presupposes changes in the law context that determines construction industry, where drawings constitute the only area of reference of the people involved.

Frank Gehry’s architectural firm is pioneer in this field as it introduced this working model in projects even from the late eighties. The huge in size “fish sculpture” in the entrance of the shopping mall of the Olympic village in Barcelona (1992), constitutes one of the first projects designed and constructed by digital media (image 13a).

Economical and temporal restrictions forced Jim Glymph, firm’s associate, to look for digital solution in construction in order to accurately produce and assembly the complex geometry of the sculpture (image). Model produced in CATIA’s (Computer Aided Three-dimensional Interactive Application) programming environment – design and construction program used mostly in aeronautics – are for Gehry’s firm and associates, the only source of design and construction information.As an important step away from the existing situation, the three-dimensional model has a key position in construction study and is the one

from which all the information are exported during the production process of the different building parts and generally of the whole construction. This fact makes the work of the specific architect extremely important for the architectural world.

image 13: strctural schemes of: a) the “Fish Sculpture”,in Barcelona (Gehry Architects), b) the hollow of a cargo ship d) BMW “Bubble” pavillion in Germany (B. Franken Architetekten) , d) the “Surface Bridge” in Singapore (IJP Corporation),

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3.[Digital Fabrication]

3.1.Definition: Digital Fabrication The digital period redefines the relationship between architectural design and production by introducing a direct conjunction between a design concept and its realization. Building projects are not only conceived and organized with the aid of digital media, but also realized through equivalent digital processes, known also as “file to factory.” The challenge of constructing architects’ morphological explorations of the late eighties transformed the question of examining the realization of certain forms to a matter of seeking appropriate tools to take advantage of digital production possibilities that started to appear.

image 14: graphic representation of the digital fabrication of a table. ( Clemens Weisshaar, Reed Kram)

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.από το αναλογικό στο ψηφιακό 3.2.From analogue to digital .3-dimensional scanning/ .3-dimensional τρισδιάστατη σάρωση scanning/ αντικειμένων

During Για πολλούς design, αρχιτέκτονες, many architects κατά την prefer φάσηworking του with models, σχεδιασμού, because η αμεσότητα they provide ενός προπλάσματος a three-dimensional είναι view σαφώς of προτιμότερη the project, rather από τηνthan επίπεδη working επεξεργασία in the two dimensional επιφανειών και surface γραμμών of paper στο χαρτί or computer ή στην οθόνη screen.

Therefore, του υπολογιστή. in theΙδιαίτερα first stages λοιπόν of their στα αρχικά development, digital στάδιαtechnologies ανάπτυξης τους were οι ψηφιακές used mainly τεχνολογίες as means of translating χρησιμοποιούνταν a modelλιγότερο form physical ως μέσοtoπρόσληψης digital space μιας through ιδέας αλλά coded περισσότερο geometric ωςinformation μέσο μετάγραφής and not τηςas από a means τον φυσικό of conceiving χώρο, όπουanείχε idea. τηνThis μορφή translation προπλάσματος, process is στον theψηφιακό, oppositeως of κωδικοποιημένη digital design construction. πλέον γεωμετρική The use of πληροφορία. three-dimensional Η διαδικασία scanning αυτή της technologies μεταγραφής aids είναι toτο produce αντίστροφο a digital της κατασκευής representation με ψηφιακά of a physical μέσα. Με model. την During βοήθειαscanning τεχνικώνprocess τρισδιάστατης a group σάρωσης, of points, παράγεται known also μια ψηφιακή as “pointαναπαράσταση cloud,” is being ενός selected φυσικούand μοντέλου. is then translated Μια ομάδαto σημείων, the control γνωστή points και με of τον a surface, όρο «σύννεφο which can σημείων» describe (point thecloud), scanned συλλέγεται object in μέσω great τηςdetail. σάρωσης και στην συνεχεία μεταγράφεται σε σημεία έλεγχου μιας Aεπιφάνειας common ηmethod οποία περιγράφει of three-dimensional κατά μεγάληscanning προσέγγιση comprises την γεωμετρία the του useπροπλάσματος. of a digital tool that traces elements Μια κοινή on the μέθοδος model’s τρισδιάστατης surface. This σάρωσης process could happen περιλαμβάνει eitherτην by χρήση hand with ενόςaεργαλείου digital arm ψηφιοποίησης that the user apply το οποίο in multiple ανιχνεύειpoints, στοιχεία orτης automatically επιφάνειας του by a device that προπλάσματος counts coordinates, (εικόνα 15).which by a sensor stays mechanically Η διαδικασία αυτή in touch μπορεί with ναthe γίνειsurface είτε χειροκίνητα of the scanned με object. έναν ψηφιοποιητικό βραχίονα των οποίο ο χειριστής εφαρμόζει σε πολλαπλά σημεία, είτε αυτόματα με Alternatively, την χρήση μιας distance συσκευής scanning μέτρησης methods συντεταγμένων, that demand the η οποία use of μέσω expensive ενός σένσορα machines διατηρείται are used. μηχανικά Theseσε machines επαφή με areτην faster, επιφάνεια more του accurate υπό σάρωση and less αντικειμένου stressful in use (εικόνα and16). they work by periodically projecting laser rays onto the surface of the model, which create clump of points or lines onto it. This process is usually record

image 15: 3d robotic digitizer “Microscribe”

ed Εναλλακτικά by two cameras. χρησιμοποιούνται οι εξ’ αποστάσεως Three-dimensional μέθοδοι σάρωσης, οιscanning, οποίες απαιτούν apart from τη χρήση the models, could δαπανηρών be applied συσκευών, to imprint αλλά an είναι existing σαφώςbuilding πιο γρήγορες, or a site. ακριβείς Alsoκαι technologies λιγότερο κουραστικές like MRI (Magnetic στη χρήση. resonance imagin) Οι συσκευές scanning, αυτές,mostly ανά διαστήματα used in medicine προβάλλουν to visualise ακτίνες body’s laserinternal στην επιφάνεια structures τουare προπλάσματος, being introduced for scanning δημιουργώντας materials/ συστάδες Last but σημείων not least, ή γραμμών has been σε αυτήν, used inοιconstruction οποίες καταγράφονται sites as control από δύοmechanism συνήθως κάμερες. not only for Από anτιςaccurate καταγεγραμμένες placement εικόνες, of theμέσω building τεχνικών elements but φωτογραμμετρίας also for observing παράγεται and preventing ένα τρισδιάστατο mistakes ψηφιακό and deviations μοντέλο, τοduring οποίο the μπορεί construction να εξαχθεί process. σε διάφορους τύπους αρχείων για την περαιτέρω ψηφιακή του επεξεργασία. Η τρισδιάστατη σάρωση, πέραν της περίπτωσης ενός προπλάσματος, μπορεί να εφαρμοστεί για την αποτύπωση μιας χτισμένης οικοδομής ή ενός ολόκληρου τοπίου, ενώ πρόσφατα η χρήση της απαντάται και σε εργοτάξια ως ελεγκτικός μηχανισμός για την ακριβή τοποθέτηση των δομικών στοιχειών (εικόνα 17) αλλά και για την παρατήρηση τυχόν αποκλίσεων και σφαλμάτων κατά την φάση της κατασκευής (Kolarevic B., 2003)

image 16: 3d laser scanner

image 17: 3d scanner for site supervision

3.3.From digital to analogue .digital fabrication/ The longstanding use of Euclidian Geometry led to the creation of design tool-operators, such as the ruler and compass, for the production of lines and circles on paper and the equivalent machines for their material production / materialization. Consequently, as Branko Kolarevic ( Kolarevic B., 2003) mentions “the conception of an architectural form entailed the conception of its method of construction and vice versa .”

A typical example of this condition is the dome of Santa Maria del Fiore cathedral in Florence, for which the period’s available techniques and methods did not allow its design and construction, as it was exceeding even the size of Pantheon’s dome Rome. Filipo Brunellesci provided a solution based on his invention of a machine to elevate materials. Therefore, architects designed what they could construct and vice versa. Representation and architectural production had a mutual relationship, which still exists in the digital era. What changes in time is the level of consistency between them.

Thus, contemporary architects take advantage of the new construction technology possibilities; being able to design with them provide a better overview of the architectural production and the project overall. Basically, computer offers an alternative view in design process, which many architects consider it to be more complete. This happens because it is now possible the three-dimensional model to contain information that constructors may translate and use directly as data to manipulate digitally controlled construction

image 18: “3DP scribe” 3d printer

machines. An increasing number of projects, of different size and budget, are accomplished with the aid of new technologies based on this principal in reasonable time and financial boundaries.

This direction is generally known with the term digital fabrication.

This field incorporates technologies of Rapid Prototyping for design and CAD-CAM (computer aided design/computer aided manufacturing) for construction (Kolarevic, 2003).

Rapid Prototyping (RP) was first applied in the mid eighties by product designers for design ideas’ presentation through physical models in 1:1 scale that were functioning as construction prototypes.

The conventional way to create a construction model starts from a three-dimensional model from which a special file type is exported that is then recognizable by a machine. This machine builds the model in one or two days. RP uses machines that constitute a small replica of the machines that are used in industry.

The term CAD/CAM basically refers to industrial object reproduction from digital models. It describes the technology that sends on the construction of a model in 1:1 scale and not only the construction of a prototype.

image 19: SLA 3d printer

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Υπάρχουν τέσσερις κοινοί τύποι συσκευών Rapid protoThere typingare και four CAD/CAM. common Τουςtypes τύπους of Rapid αυτούςprototyping περιγράφουμε and εν συντομία CAD/CAM με τον machines όρο, συσκευές that areCNC condensed (computer under the numerical term CNC control)/cutting (computer numerical and millingcontrol)/cutting devices. and Αναφορικά milling είναι devices. οι εξής: -2D cutting devices (vinyl, laser cutters)/ (εικόνα 22) -2D -subtractive cuttingdevices devices (milling (laser,water machines)/ jet cutters (εικόνα 19) etc)/ -subtractive -additive manufacturing devices (milling devicesmachines)/ / -additive -formativemanufacturing manufacturing devices/ devices / -formative manufacturing devices/ Η τεχνική της ογκοαφαίρεσης (εικόνα 19) είναι η The παλαιότερη technique μορφή of mass ψηφιακής extracting κατασκευής. is the oldest Τα πρώτα form of παραδείγματα digital construction/fabrication. με την χρήση της τεχνικής In theαυτής field στον of architecture, τομέα της αρχιτεκτονικής the first examples συναντώνται of thisστις technique αρχές του use happened 1970 στην Αγγλία at the beginning για την παραγωγή of the seventies αρχιτεκτονικών in England μοντέλων. for architectural Μεγάλα αρχιτεκτονικά model production. γραφεία στις WellΗνωμένες known architectural Πολιτείες όπως firms οι Skidmore, in UnitedOwings States and of America, Merrill’s (SOM) such as από Skidmore, το Σικάγο,Owings έχουν χρησιμοποιήσει and Merrill’s (SOM) εκτεταμένα in Chicago have τεχνικές extensively CAD-CAMused για την CAD-CAM παραγωγή techniques αρχιτεκτονικών for architectural μοντέλων και model για μελέτες creation κατασκευαστικών and for studies on construction συναρμογών. assemblies. Στις αρχές της δεκαετίας του 1990, αυτοματοποιημένες At συσκευές the beginning όγκο-αφαίρεσης of nineties, χρησιμοποιούνται automated machines για την of mass-subtraction επεξεργασία οικοδομικών are used υλικών, for processing όπως τις πέτρες building για materials, τον καθεδρικό suchτου asΑγ. theΙωάννη stonesστη forΝέα Saint Υόρκη, John’s καιCatheτις dral κολώνες in New τηςYork, Sagrada andFamilia Sagrada στηνFamilia’s Βαρκελώνη. columns Η μελέτη in Barcelona. του Frank Gehry Frankγια Gehry’s ένα συναυλιακό study forκέντρο Walt Disney της Walt concert Disney hallστο in Los Los Angeles Angelesαποτελεί constitutes το πρώτο the first παράδειγμα example of χρήσης usingτεχνολογίας CAD-CAM CAD/CAM technology γιαfor την stonework παραγωγήconstruction. λιθοδομής.For Γιαthe το αρχικό initial model μοντέλο ofενός a building τμήματος part του with double κτιρίου curvature, με διπλή καμπυλότητα, stone panelsπέτρινα were processed panel κόπηκαν in 1:1 scale και επεξεργαστήκαν and were milled σε in κλίμακα Italy. They 1:1 στην were Ιταλία thenκαι transεν ported συνεχεία through μεταφέρθηκαν sea to Los μέσω Angeles θαλάσσης where στοthey Los Anwere assembled geles ,όπου on και site συναρμολογήθηκαν on a metal frame. επί τόπου πάνω σε μεταλλικό σκελετό.

CAD-CAM Η τεχνολογία technology CAD-CAM is εφαρμόζεται now applied πλέον in multiple με ποικίλους ways τρόπους in architecture; στην αρχιτεκτονική constructing όπως για molds την κατασκευή (outside the καλουπιών (εκτός εργοταξίου) και την επί τόπου χύτευση τους, καθώς επίσης και για την μορφοποίηση υαλοπινάκων με πολύπλοκη γεωμετρία.

Στα μηχανήματα τεχνολογίας CNC, ένα υπολογιστικό building σύστημαsite) διαχειρίζεται and in situ τηνcasting κίνηση concrete και τις λειτουργίες into them or morphing της κεφαλής glass χρησιμοποιώντας panels with complex ένα σύνολο geometry. κωδικοποιημένων οδηγιών.

In Η CNC γεωμετρία (computer εισάγεται numerically σε ένα λογισμικό controlled) επεξεργασίας machines aδευτέρου computational βαθμού,system (post-processing deals withsoftware) the movement το οποίο and αναπαράγει the functions αριθμητικά of theτιςhead οδηγίες by using οι οποίες a group μετά of coded δίνονται guidelines. ως δεδομένα Theστην geometry συσκευή. is introduced Οι υπολογιστικές, in a post-processing αριθμητικά ελεγχόμενες software οδηγίες that numerically (computer numerireproduces the callyguidelines controlled)that ελέγχουν afterwards την κίνηση, serve την as device ταχύτητα inputs.

The και τη computational, συχνότητα περιστροφής numerically τηςcontrolled κεφαλής και guidelines των check κατευθυντήριων movement, μοτέρ, speed καθώς and επίσης frequency και την of the αλλαγή head evasion αρίδων, and την παροχή the directional ψυκτικούmotor, και άλλες as well λειτουργικές as the milling παραμέτρους bit change,της the συσκευής. refrigerant Καθώς supply η αφαίρεση and other functional όγκουdevice για τηνparameters. μορφοποίησηAsενός morphing στερεούaμπορεί solid object να through γίνει με πολλαπλούς mass-subtraction τρόπους, could η αναπαραγωγή happen in multiple ενός ways, κατάλληλου the reproduction “πλάνου” διαδρομής of a suitable της κεφαλής, toolpathδεν forείναι is not απλή anυπόθεση. easy case. Το πλάνο This toolpath αυτό εκφράζεται is expressed με έναthrough CNC aπρόγραμμα, CNC executable το οποίο program δεν είναιthat κάτιisάλλο no more από μια than σειρά a sequence κωδικοποιημένων of coded εντολών commands τις οποίες the machine το μηχάνημα runs. εκτελεί (G code).

CNC Τα CNC programs προγράμματα are made είναιof φτιαγμένα word commands, από εντολές, each one οι οποίες of which αποτελούνται has a letter από asλέξεις, address καθεμία and aαπό relative τις numerical οποίες έχειvalue. ένα γράμμα The soωςcalled διεύθυνση procedural και μιαfunctions, σχετική which αριθμητική for example τιμή. Οι control αποκαλούμενες the movement προεργαστικές of the head, are λειτουργίες, usually denoted οι οποίεςwith για παράδειγμα the letter G.ελέγχουν In a typical την CNC program, κίνηση τηςthe κεφαλής majority σημαίνονται of “words”πολλές are these φορές procedural με το functions. γράμμα G. For Σε ένα thatτυπικό reason, CNCthe πρόγραμμα, users of CAM η πλειοψηφία (computer των aided “λέξεών” manufacturing) είναι οι προεργαστικές machines αυτές often λειτουργίες. refer to CNC code Για τον asλόγο G-code. αυτό, ο CNC κώδικας, πολλές φορές αναφέρεται ως κώδικας-G, μεταξύ των χειριστών In μηχανημάτων the followingCAM parts, ( computer four CNC aided machine manufacturing). technologies will be described as well as the process of assembly, Both Παρακάτω constitute αναφέρονται an important αναλυτικά part οι ofτέσσερις digital fabrication. τύποι μηχανημάτων CNC καθώς επίσης και η διαδικασία της συναρμολόγησης, η οποία αποτελεί αναπόσπαστο κομμάτι του digital fabrication.

image 20: CNC milling machine

image21: Laser cutter

image 22: CNC plasma cutter

image 23: 2d vinyl cutter

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image 24: Waterjet cutter

image 25: water jet nozzle and diagrammatic section

image 26: Movement analysis diagram of the head of a 3 and 5-axis milling machine.

3.4.Two dimensional fabrication

3.5.Subtractive fabrication -subtractive devices (milling machines)

Two-dimensional cut with CNC machines is the most common type of digital fabrication. CNC machines range in size and accordingly the surfaces they can process are of different sizes (image). The existing cutting technologies, such as the laser-cutter, the water-jet-cutter and the plasma-cutter allow movement in two directions, either of the head-cutter or of the surface upon which the material is placed (placed on panels of specific dimensions) or a combination of the two. In plasma-cutter, an electric arc is transmitted through a motor jet of compressed gas to the head cutter. In that way the gas is transformed to plasma with the aid of high temperature (25000F), which is then retransformed into gas as it transfers the heat to the cutting area.

The mass-subtraction machines function upon the subtraction of specific material mass from solids, by using electro-chemist-mechanic-subtractive procedures (multi axis milling) (image). The material milling could be axis, surface of mass restricted. In the axis restricted devices, such as the lathe, the part of the material that is under process could be moving around an axis of evasion, while the head has two axis of movement. The surface restricted devices work exactly as the cutting devices mentioned above.

-2D cutting devices (laser,water-jet,vinyl cutters)

In water-cutter, a motor of high pressure transmits water in combination with solid polishing particles into a small diameter end effector (nozzle). Thus, the mixture is transformed to a focused beam that causes immediate erosion. As a result, clear and accurate cuts are being produced.

In laser-cutter, a high frequent bundle of infra-red light is being used in combination with a motor of ejecting gas of high pressure (CO2) to locally melt or burn the cut material.

In between these technologies, huge differences exist as far as the material that could be processed, the maximum cutting depth and the time needed are concerned. Thus, while the laser -cutter machines could cut materials that absorb light radiation (i.e. wood), water-cutting machines could cut almost all material. Laser-cutter machines could cut efficiently and in short period of time cross-sections of 16mm, while water-cutting machines could cut larger cross-sections (until 38cm) of even hard materials, such as titanium.

The milling process of three-dimensional solids is the direct development of two-dimensional cutting.

Furthermore, three-dimensional material subtraction is possible with the addition of the head’s ability to move in another axis. Due to the inherited attributes of the three-dimensional material milling, the range of the forms that could be produced with the aid of these machines is limited. For that reason, machines with 4 and 5 directional movements have been imported. In the machines of 4 directions, another evasion axis is added either to the head or to the devices’ working surface. In the machines of 5 directions, both head and working surface have evasion ability, maximizing, thus, the ways the head could be adjusted to the solid. In that way, a wider range of shapes could be provided.

Tools that are placed in the head vary in size depending on the work phase. Milling tools of larger cross-section are used for material subtraction, while ones of smaller cross-sections are used for surfacing/finishing. The speed of the end effector could be adjusted according to hardness or other material attributes.

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.additive fabrication/ προσθετικήfabrication κατασκευή/ 3.6.Additive -additive manufacturing devices

/additive manufacturing devices/ Additive fabrication describes the step by step H προσθετική κατασκευή την κατάinβήμα morphing of an object byεμπεριέχει adding material layers, μορφοποίηση ενός αντικειμένου τηνmass-subtracπρόσθεση following the reverse process ofμεthe υλικού σε επίπεδα, ακλουθώντας την αντίστροφη tive fabrication.

Often it is mentioned as layered διαδικασία από αύτη όγκο-αφαιρετικής κατασκευής. manufacturing, rapidτης prototyping, solid free form Αναφέρεταιor συχνά ως layered manufacturing, rapid fabrication desktop manufacturing.

All additive prototyping,technologies solid free formshare fabrication ή desktop manufabrication the same concept as facturing. Όλες οι τεχνολογίες κατασκευής far as it concerns the digital προσθετικής model analysis in layμοιράζονται την ίδια λογική όσον αφορά την ανάλυση ers.

The information for each layer is transferred to τουdevice’s ψηφιακούhead μοντέλου σε επίπεδα-στρώσεις. the and the physical model isΗbeing πληροφορία το κάθε επίπεδο-στρώση μεταφέρεται produced in για successive layers. The most common στην κεφαλή της συσκευής και το φυσικό additive fabrication technologies are: μοντέλο παράγεται σε αλληλεπίθετα στρώματα. Μετά (Stereo-lithography). την εισαγωγή στο εμπόριο μιας συσκευής -SLA 3d-systems Company βασισμένης παραπάνωinτρόπο λειτουργίας, was the firstστον to introduce the market a device γνωστόon επίσης και ως way στερεολιθογραφία, από that, την based the above of function. After 3d systems, μια σειρά αντίστοιχων συσκευών aεταιρεία succession of similar devices appeared.

These έχει εμφανιστεί. Οι συσκευές αυτές χρησιμοποιούν μια devices use multiple materials and clot processes πλειάδα και διαδικασιών με βάση τηνas based onυλικών light and/or thermal πήξης radiation as well φωτεινή ακτινοβολία, την θερμική ακτινοβολία και την chemicals’ application.The technology is based εφαρμογή on polymerχημικών. liquid materials, which become solid when exposed to laser radiation. Head ray creates a section of the model inside a vat that contains the -Η στερεολιθογραφία/SLΑ βασίζεται σε πολυμερή susceptible to radiation liquid polymer.

The trace στοιχεία υγρής μορφής, τοisοποία στερεοποιούνται όταν of the nozzle’s toolpath, the area where radiation στην laser ακτινοβολία. κεφαλής isεκτίθενται being applied,and solidifies inΗaακτίνα rouglyτης 1/10 mm διαγράφει μια τομή τουwhich μοντέλου, μέσα ένα δοχείο increment.

This layer, rests on aσε“sinking” με το ευπαθές στην one ακτινοβολία υγρόinto πολυμερές. Στην surface, is moved step lower the container περιοχή πουcreates έχει δεχτεί ακτινοβολία, στο “ίχνος” and the ray theτην next model section.

This δηλαδή is τηςrepeated κίνησης της process for κεφαλής, all layers,δημιουργείται in which theένα model στρώμα στερεού υλικού. Το στερεοποιημένο isλεπτό analyzed, until its completion.

Towards the end of τμήμα, το οποίο πάνωthe σε μια βυθισμένη the process the ακουμπά surface with solid model is taken επιφάνεια, υποβαθμίζεται ένα βήμα μέσα out of the container, the κατά model further clotsστο and the δοχείο και η ακτίνα την επόμενη τομή του excess material is διαγράφει being subtracted. μοντέλου. Η διαδικασία αυτή επαναλαμβάνεται για όλα ταtechnology επίπεδα στα(Selective οποία έχει αναλυθεί το μοντέλο -SLS Laser Sintering), μέχρι τουlaser (εικόνα Στο τέλος της of in thisολοκλήρωσης technology the ray31). creates sections διαδικασίας η επιφάνεια με το στερεοποιημένο an object and then condenses in successiveμοντέλο layers ανασύρεται απόforming, το δοχείο, το μοντέλο πήζει περαιτέρω metal powder, thus, the object. και αφαιρείται τυχόν επιπλέον υλικό. powder are con-3DP technology, layers of ceramic nected, in the same concept, to create an object.

-LOM technology ( Laminated Object Manufacturing), material either in sheets (paper of plastic), or in rolls are connected (lamination technology) and are

then cut with laser.

-Στην technology selective laser(Fused sintering/SLS (επιλεκτική συμπύκνωση -FDP Deposition Modeling), In με laser) τεχνολογία, η ακτίνα laser διαγράφοντας πάλι την this technology a semi-liquid material -- and most τομή ενός αντικειμένου, συμπυκνώνει ανά στρώματα usually a hot thermoplastic -- is extruded from a σκόνη μετάλλου, μορφοποιώντας έτσιhead το αντικείμενο (εικόνες temperature-controlled print to produce fairly 28,29).

-Στην 3d printing/3DP τεχνολογία κεραμικής robust objects to a high degree ofστρώσεις accuracy.

A key πούδρας ίδια λογικήcan για να benefit ofσυγκολλούνται this techniqueμεisτην that objects be made δημιουργήσουν αντικείμενο (εικόνα 27). used in of out of exactlyτοthe same thermoplastics -Στην Laminated object Manufacture/LOM traditional injection moulding.

Most FDM τεχνολογία, 3D printφύλλα (χαρτίboth ή πλαστικό), είτε σε μορφή ρολού ers canυλικού print with ABS (acrylonitrile butadiene συγκολλούνται μεταξύ τους (τεχνική τηςbioplastic φύλλωσης-called styrene), as well as a biodegradable lamination), και στην κόβονται με laserorganic PLA (polylactic acid)συνέχεια that is produced from -Στην Fused to Deposition Modeling/FDΜ τεχνολογία κάθε alternatives oil τομή του υπό κατασκευή αντικειμένου παράγεται με την τήξη ενός πλαστικού νήματος, το οποίο στερεοποιείται με την -MJM (Multi-jet Manufacturing).

As an alternative έκθεση σε κρύο αέρα (εικόνα 30).by Objet, is Multito FDM,του a technology, developed -Στην Multi-jet Manufacture/MJM τεχνολογία μιαtwo Jet-Manufacturing or Polyjet Matrix.

This jets τροποποιημένη κεφαλή εκκρίνειfrom λιωμένο θερμοπλαστικό liquid photocurable polymers a multiple nozzle κερί σε πολύEach λεπτές στρώσεις, τηνisμια μετάby τηνa άλλη, για την print head. object’s layer cured UV light δημιουργία τρισδιάστατων στερεών σωμάτων. immediately after it has been printed.

One of the key benefits of this process is that it allows printing Λόγω περιορισμένου μεγέθους to takeβέβαια placeτου in multiple materials simplyτων byαντικειμένων varying πουcombination μπορούν να παραχθούν με τις παραπάνω τεχνολογίες the of the photocurable polymers jetted αλλά the και τους χρόνους κατασκευής, from printπαρατεταμένους head. You can learn more about this έχουν περιορισμένη εφαρμογή στον αρχιτεκτονικό very impressive technology σχεδιασμό και κατασκευή. Στον σχεδιασμό κατά κύριο λόγο χρησιμοποιούνται για την παραγωγή ογκομετρικών με The above mentioned technologies since their inπολύπλοκηin καμπύλη γεωμετρία, στην applications κατασκευή για την troduction the 80’s have hadενώ limited μαζική παραγωγή εξαρτημάτων, όπως μεταλλικά στοιχεία in architectural design and construction due to the ελαφρών μεταλλικών κατασκευών. narrow range of object sizes they could produce and Πρόσφατα βέβαια, διεξάγεται time έρευνα για τηνThey κατασκευή the prolonged construction needed. are μεγαλύτερης δομικών με τον ψεκασμό used, though,κλίμακας in design mostlyστοιχειών for the production of κονιάματος. Έτσι, καθώς ο ψεκασμός τουand υλικού ελέγχεται solids with complex curvy geometry in construcψηφιακά, είναι δυνατή η ακριβής υλικού tion for the mass production of πρόσθεση components, such as σημειακά γιαofλόγους ενίσχυσης αλλά και λοιπών στοιχείων, metal parts light metal constructions. όπως αισθητήρες θερμοπομπούς, οι οποίοι research μπορούν Since some yearsκαι now, there is an ongoing έτσιthe ναconstruction ενσωματωθούν κατασκευή με ένα πλήρως on ofστην bigger scale structural parts αυτοματοποιημένο by spraying mortar.τρόπο.

Therefore, as the deposited material is digitally controlled, it is possible not only to accurately add material in specific points for strengthening reasons, but also to alter its mechanical properties locally (i.e. elasticity) as well as add other parts such as sensors and thermo-transmitters, which could be now incorporated to the construction with a totally automated technique.

image 27: working diagram of 3DP 3d-printer image 28,29: working diagrams of a SLS 3d printer

image 30: working diagram of a FDM 3d printer image 31: working diagram of an SLA 3d printer

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3.7.Formative fabrication -formative manufacturing devices In formative manufacturing mechanical forces, restricting molds, heating or steam are applied on the processed object. The aim is to achieve the desired shape by causing the plastic deformation of the material in one or multiple axis.

For example, lateral forces above steel’s elasticity limit might be applied to a reinforcement so that it can be permanently shaped into a desired form. Another common technique is the application of high temperature locally and the direct bending of the exposed area. The shape of doubly curved surfaces can be approximated with the description of any planar geometry by a gird of adjustable in height metallic pins. Each pin corresponds to the UV (contol) point of a given surface. This technique is mostly used for the morphing of glass panels as well plastic and metal sheets. Surfaces that are curved along on axis can be fabricated by the numeric control of thin rods, pipes or stripes of an elastic material (i.e. wood, steel), which serve as guides for the morphing of a corresponding material

.formative fabrication/ μορφοποιητική κατασκευή/ 3.8.Assembly -assembly devices and mechanisms

/formative manufacturing devices/

The assembly process constitutes an essential μορφοποιητική κατασκευή μηχανικές part ofΣτη digital fabrication and refers to theδυνάμεις, comπεριοριστικά καλούπια, θερμότητα ή ατμός position of the different building components of εφαρμόζονται πάνωfurniture) στο υπό επεξεργασία υλικό. Ο an object (i.e. building, in one piece. σκοπόςasείναι να προσδώσουν μορφή It functions a control process την for επιθυμητή fabrication, μέσω του ανασχηματισμού τη παραμόρφωσης, as it directly reveals possible ήweak connecting προς ένανthe άξονα είτεstages ως προς of μιαthe επιφάνεια points ως even from early design αναφοράς. Για παράδειγμα, το ανασχηματισμένο process.

At the same time it introduces a very υλικόdesign μπορεί factor; να έχει υποστεί πλαστική παραμόρφωση important the ability to design μέσωmultiple διαδικασιών όπως η πέραν της ελαστικής του parts with connection possibilities. αντοχής στρέβλωση. Πιθανήof είναι ακόμη η σημειακή he in situ digital manipulation a building θέρμανση του και κατόπιν η κάμψη του.digital Η μορφή assembly increases the concept of its σύνθετων επιφανειών με διπλή καμπυλότητα μπορεί fabrication. να προσεγγιστεί με την περιγραφή της γεωμετρίας

τους σειρές, ρυθμίζομενων καθ’ ύψος,the αριθμητικά The use of από digital models could facilitate ελεγχόμενων καρφιτσών. καρφίτσα αντιστοιχεί accurate placement of everyΚάθε structural object to σε ένα σημείο της πολύπλοκης γεωμετρικά επιφάνειας. the appropriate position.

Traditionally, builders Η τεχνική αυτήdrawings χρησιμοποιείται για την μορφοποίηση consulted drafting for dimensions and υαλοπινάκων, ελασμάτων πλαστικού καθώς(meκαι coordination and by in situ measurements καμπύλων επιφανειών (εικόνα 32). ter, plumb etc), μεταλλικών suitable inscriptions and started Καμπύλες επιφάνειες, κατά construction μια μόνο διεύθυνση, to build.

Nowadays, in many sites να παραχθούν με την αριθμητικά ελεγχόμενη all overμπορούν the world, new digital controlled techσωλήνων, ή λωρίδων κάποιου niques,κάμψη suchλεπτών as theράβδων, electronic levelling and area ελαστικού (π.χ. ατσάλι, ξύλο), που λειτουργούν measuring that υλικού are based on a universal referως οδηγοί για τηνare μορφοποίηση υλικού. ence system (GPRS) used for του the εκάστοτε accurate assembly of structural elements.

Annette LeCuyer, which was involved in the construction of Guggenheim Museum in Bilbao, informs us that “the building was constructed without in situ measurements ”. During the production phase of the structural elements

image 32: Production of foam molds with CNC machine for the in situ casting and digital controlled assembling of wall panes for the Zollhof office bui

of the building each one of them was coded (with the use of a bar-code) and the important intersection points with other building components were mentioned.

Afterwards, at the construction site, the placement of each component, recognized from the bar-code, were directly given by the three-dimensional model (CATIA). Special preview laser equipment, directly connected to the digital model, was scanning the under construction building and was ensuring the accurate placement of all parts, as was defined by the model.

Annette LeCuyer mentions that “these techniques, despite being relatively new in building construction, constitute common practice in aeronautics and ship-building.�

Furthermore, the information exported from a three-dimensional model, as far as the geometry is concerned, could be given as inputs for controlling the movement of an industrial robotic arm that could execute a series of actions in a construction site. In Japan, a series of robot ic devices have been developed specialized in transporting and assembling parts.

ilding complex in Duesseldorf (Gehry Architects)

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4.[ Digital design fabrication/DDF ]

4.1.Definition: Digital Design Fabrication Digital design fabrication, a term that has been extensively analyzed by Larry Sass (Sass, L., 2006) professor in architectural department of MIT, could comprise all the information mentioned so far. DDF aims to compose the flexibility of traditional design on paper, the accuracy and modeling ability of digital design and the direct connection with construction that digital fabrication offers. The goal is to create an environment that will support design – through interaction – with the production of structural elements and physical models. This will be supported by being in direct contact with the flexibility, accuracy and manipulation ability of the information that the describing objects’ environments have. The combination of two opposing characteristics is being provided; on the one hand the necessary freedom and flexibility of the design process and on the other hand the accuracy and ability of a detailed described fabrication process that characterize CAD-CAM devices

4.2.The notion of digital design fabrication:Design models,Design information models,Building Information Models (BIM) DDF process produces two model types. On the one hand design models exist as one and only object. On the other hand design information models exist as an object constituted by parts that follow construction restrictions. In massing models of early design phases one studies the arrangement of volumes in relation to the space requirements implied by a given brief.

They are described by volumes or surfaces in CAD and are quickly produced by rapid prototyping machines. These small in size models are valid for volumetric and morphological assumptions. They do not follow a specific construction method, nor are described by any material.

The second model type refers to the assembly of the different parts. Depending on their design level, they are characterized by variety in the degree of detail and the construction information they carry. Design information models constitute an abstract way to describe buildings as design products (Eastman, 1999). In this model type a degree of complexity starts to arise, as they could be shaped from many materials and have relatively big size. These models offer the possibility of evaluating design and construction process of some details, while they could provide a sense of the interior space. This depends on their scale that could vary according to the design phase. They cover all the phases between the first schematic design models and the final model as well. The developement of such digital models is quite time consuming as does their production from RP machines.

An advantage of DDF is its ability to provide models in all in-between stages, from the early design phases until the BIM (building information model). The latter concentrate on representing a design project in 1:1 scale, without causing

important changes in model’s geometry, only adding on that more information. The goal of this method is to record construction information from data bases on a three-dimensional object of design information that sequentially ends up being the construction model.

With the term structural unit we refer to any part that structurally participates to a building, such as for example a brick. Alternatively the term component is used, which is closer to mechanical engineering. This is not necessarily out of context as it is possible in the near future the construction of a building to be considered similar to a machine assembly. The term component is most commonly used to refer to a structural unit. The design of structural units is a significant parameter of DDF that is also connected to the assembly properties. This lies in the fact that the use of rapid prototyping machines is possible to produce structural elements that are directly related to design and thus customized, as well as multifunctional. Therefore, the aim is to model and construct “smarter,” parametrically controlled structural units that can offer multiple ways of i.e connecting. Furthermore, it is essential for these units to have the same global behavior, but not necessarily same local crosssection or form. The goal for these units is to be able to respond to the construction restrictions that the available technology (CAM) and assembly methods provided, while they could be unique for each project. This comes as a consequence of the introduction of CNC machines, as it is equally easy and economically efficient to produce 1000 unique components and 1000 identical ones. The possibility of unique structural component mass production re-introduced the term mass customization in the field of architectural design and construction.

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.component design/ σχεδιασμός δομικών μονάδων/ 4.3.Component design With the term structural unit we refer to any part that Με τον όρο δομική μονάδα σε for example structurally participates to aαναφερόμαστε building, such as οποιοδήποτε στοιχείοthe συμμετέχει δομικά σε ένα which a brick. Alternatively term component is used, κτίριο όπως για παράδειγμα ένα τούβλο. is closer to mechanical engineering.

This Εναλλακτικά, is not necessarily χρησιμοποιείται όρος εξάρτημα ο οποίος μας out of context asκαι it isοpossible in the near futureβέβαια the conπαραπέμπει μηχανολογία. Αυτό δεν είναιtoαπαραίτητα struction of aστην building to be consider similar a machine άτοπο αν αναλογιστεί κανείς πως δεν αποκλείεται assembly.

In foreign bibliography, they already useστο the κοντινό μέλλον η κατασκευή κτιρίου να θεωρείται term component to refer to aενός structural unit. εφάμιλλη μεofτηstructural συναρμολόγηση μηχανής. Ήδη στην The design units is aμιας significant parameter ξένη βιβλιογραφία με τον όρο to του εξαρτήματος/compoof DDF that is also connected the assembly properties. nent αναφέρονται αυτόν τηςrapid δομικής μονάδας.maThis lies in the fact και thatσεthe use of prototyping Ο σχεδιασμός δομικών μονάδων είναι μια σοβαρήthat are chines is possible to produce structural elements παράμετρος του are DDFdirectly που συνδέεται καιdesign με τηνand διαδικασία not customized, related to could της συναρμολόγησης/ 35,36). Αυτόis to perform more than oneassembly function.(εικόνες Therefore, the aim έγκειται στο γεγονός πως με την χρήση συσκευών construct “smarter, ” parametrically controlled bricks that rapid prototyping δυνατή η παραγωγή δομικώνit is have more abilitiesείναι thanηbeing piled up. Furthermore, στοιχειών, ταthese οποίαbricks/units δεν είναι τυποποιημένα, σχετίζονται essential for to have the same behavior, άμεσα τον σχεδιασμό και μπορούν εν δυνάμει ναThe but notμεnecessarily the same cross-section or form. πραγματοποιήσουν παραπάνω μια λειτουργιά. goal for these units is to be ableαπό to respond to the construction restrictions that the available technology (CAM) and assembly methods provide, while they could be unique for each project. This comes as a result of the fact that for a CNC machine is equally easy and economically efficient to produce 1000 unique components and 1000 alike. The possibility of unique structural component mass production introduced the term mass customization in the field of architectural design and construction.

image 34: dome study-3d printed building components, (Saas L)

Επιδιώκεται λοιπόν η κατασκευή «εξυπνότερων» τούβλων, παραμετρικά ελεγχόμενων, τα οποία έχουν την ικανότητα όχι μόνο να στοιβάζονται, ενώ δεν είναι απαραίτητο να έχουν την ίδια διατομή ή μορφή παρά μόνο την ίδια συμπεριφορά. Στόχος είναι τα στοιχεία αυτά να ανταποκρίνονται στους κατασκευαστικούς περιορισμούς που επιβάλει η διαθέσιμη τεχνολογία (CAM) και μέθοδοι συναρμολόγησης τους ενώ μπορεί να είναι μοναδικά για κάθε μελέτη. Αυτό έγκειται στο γεγονός ότι είναι το ίδιο εύκολο και οικονομικά αποδοτικό για ένα μηχάνημα CNC να παράγει 1000 μοναδικά εξαρτήματα όσο και 1000 ταυτόσημα. Η δυνατότητα μαζικής παραγωγής μοναδικών δομικών στοιχείων, διαφορετικών μεταξύ τους, εισήγαγε τον όρο του mass customization στο πεδίο του αρχιτεκτονικού σχεδιασμού και παραγωγής.

image 35: dome studyscaled model of structural components assembly (Saas L)

4.4.Mass-customization VS mass-production The ability to mass-produce one-off, highly differentiated building component with the same facility as standardized parts, introduced the notion of “Mass customization� into bulding design and production.

Mass production, the Post-Fordian paradigm for the economy of the 21st century ,was defined by Joseph Pine as the mass production of individuallycustomised goods and services, thus offering a tremendous increase in variety and customization without corresponding increase in costs (Kolarevic, 2003). Under this light, mass customization offers not only a remarkable increase in variety, but also a possibility of personalization without increasing the production cost. The term was established by Stan Davis in Future Perfect (Davis, 1987), while Alvin Toffler perceived it as a technological capability in 1970 (Kolarevic, 2003).

Modernism principles of the 20th century mostly followed fordism model of industrial production and joined construction production with concepts such as standardization, prefabrication and in situ placement. The logic of industrial production imposed geometric simplicity over complexity and repetitive use of low cost mass produced components. The existing characteristics of this production type have been altered as digital controlled devices can produce unique and complex in shape components, the cost of which remains affordable. In other words, variety does not stand opposite

economic efficiency. It is therefore obvious that mass customization is appropriate for construction production, as most of the buildings could be considered as original products that are hardly mass produced. Thus in a typologically simple building, such as an office tower, design coding and parameterizing hides a retaliation, that of getting a wide range of design solutions by making small changes in design.

For example, it is possible to produce structural elements, which could range depending on the local conditions and the forces that they curry.

Digital design mass customization initiates a new sequential concept in architecture that could be based upon the spatial variety and difference. Modern aesthetics considered residence as a constructed housing machine, which through mass customization could make design a privilege of the people and not only of the elite. The modern translation of this concept does not impose a homogenous condition nor establishes a prototype that covers all situations (one size fits all), but suggests the uniqueness and difference that could be accomplished through the digitally controlled variety and the at will parameterization. We should keep in mind that this condition, to a certain level, has been applied. Nike, for example, through its Nike ID project offers the consumer the possibility of selecting color and material on specific products in the same price with the rest of its products. We may soon have the possibility of altering the design or even creating a personal one.

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.η παράμετρος της κλίμακας 4.4.The parameter of scale/ Scale-ability

.περιγραφή της κατασκευής

Πριν τηνto εισαγωγή των τεχνολογιών των συσκευών rapid Prior the introduction of rapid prototyping prototyping και CAD-CAM, υπήρχε έναduring χάσμα στα and CAD-CAM technologies, the ψηφιακά first σχεδιαζόμενα μοντέλα τα οποία of πρακτικά είχανεtools years of the introduction digitalδεν desing κλίμακα. Έτσι πολλέςthere φορές was οι αρχιτέκτονες αντιμετώπιζαν in architecture, a gap in digitally deτοsigned πρόβλημα της προσαρμογής του ψηφιακού models, which practically wereμοντέλου characστην πραγματικότητα. Με την εισαγωγή terized by the absence of scale του andDDF, materiality. επιβάλλεται ο άμεσα συσχετιζόμενος με την υλική του the Therefore, architects many times confronted αναπαράσταση σχεδιασμός.the Αυτό σημαίνει πως το problem of adjusting digital model toψηφιακό reality. μοντέλο ως ένα βαθμό υλικούς περιορισμούς, Duringεμπεριέχει DDF process, a direct relation between καθώς στηνand περίπτωσή που αυτό δεν συμβαίνει δενThat είναι design materialization is necessary. δυνατή ούτε η ψηφιακή παραγωγή Ο σχεδιαστής means that the digital modelτου. embodies to an έχοντας γνώση των ορίων τουrestrictions, (διαθέσιμου) μηχανήματος extend materialization which deterψηφιακής φροντίζει αυτό σχεδιάζει mine itsκατασκευής digital production.

Theπου designer takes ναinto είναιconsideration προσαρμοσμένοthe ανάλογα. Για παράδειγμα θα restrictions of the availαναλύσει μια τρισδιάστατη επιφάνεια σε and panelmakes τέτοιωνsure able digital fabrication machine διαστάσεων ώστε να μπορούν να επεξεργαστούν από ένα that his/her design is adjusted to it. laser cutter, ή θα σχεδιάσει ένα δομικό στοιχείο το οποίο θαFor μπορεί τυπωθείhe/she από μια will συσκευή στερεολιθογραφίας/ instnace, analyze a three-diSLA device για να αξιολογηθεί. Σε πιο the πρακτικό επίπεδο τα mensional surface in panels, dimensions of design information παράγονται κύριο λόγοor which could bemodels processed by a κατά laser-cutter, από συσκευές prototyping ενώ τα building informawill designrapid a structural element that could be tion modelsby από CNC. so as to be able printed anμηχανήματα SLA 3d printer

Ένα ακόμη βασικό του DDF, είναι τοbuilding γεγονός (DIM), while CNCστοιχείο machines produce πως η άμεση σύνδεση του σχεδιασμού με την παραγωγή information(BIM) models.

to be evaluated according to structural perfomance. In a practical level rapid prototyping machines produce design information models

π.χ. εξαρτημάτων εισάγει άμεσα την παράμετρο της

αποτελεσματικότητας.description Οι τεχνικές παραγωγής και οι 4.5.Construction

μέθοδοι λειτουργίας των μηχανημάτων αποκτούν μια

σημαντικήbasic θέση στον αφού εξασφαλίζουν την Another DDFσχεδιασμό characteristic is the fact that καλύτερη των εργασιών. Ιδιαίτεραwith σημαντικός κρίνεται the directροή connection of design production φυσικά και ο τρόπος περιγραφής σχεδιασμού,the καθώς (i.e. components) introducesτου immediately η μετάφρασηofτου μοντέλου σε κώδικα G εισάγεται ως parameter effectiveness.

Machines producδεδομένο για την υλοποίηση από τα μηχανήματα CNC tion techniques and function methods gain an (εικόνα 39). position Έτσι μια συσκευή κοπής τηνa important in design aslaser, theyαπαιτεί ensure δυσδιάστατη μιας τρισδιάστατης γεωμετρικής better work περιγραφή flow. Furthermore, the method of φόρμας,description ενώ μια συσκευή additive fabrication απαιτεί design is also extremely important, τηνmodel’s τρισδιάστατη περιγραφή κελύφους και μόνο as translation in του G code is introduced μιας γεωμετρικής φόρμας. Η περιγραφή εκτός των as input for its materialization fromαυτή CNC maγεωμετρικών δεδομένων περιέχειmachine και το μονοπάτι που θα chines.

Thus, a laser-cutter demands a ακολουθήσει η κεφαλή του μηχανήματος, πράγμα που two-dimensional description of a three-dimenπροσθέτει άλλον έναν παράγοντα κατά την φάσηfabriτου sional geometric form, while an additive σχεδιασμού. cation machine demands a three-dimensional description of the shell of only one geometric form. This description apart from the geometric inputs involves also the path that the machine’s head will follow, which constitutes another design factor.

00001 N005 G54 G90 S400 N01 G00 X1 Y1 N015 G43 H01 Z1 M N020 G01 Z-125 F3.5 N025G00 Z-1 N030 X2.

N035 G01 Z-1 M09 N040 G00 Z-1 Z0 N050 M30 N055 M35 N060 G00 Z-2 M08 N065 G55 G95 S450 N070G00 Z-1 N0G00 Z-1 image 38: part of a code controlling the direction of a CNC (G-Code) and analysis of the motion workflow of an RP device.

imagw 36: multiple 3d prints of a design procedure for a concert hall ( Gehry Architects)

image 37: examples of 3d prints in different scales and with varying degree of details

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5.[case studies]

In the next chapter, we will provide a more specific view of DDF’s application in architecture, through a selective reference to realized and experimental projects. The selected examples vary in program, scale, budget and complexity; so as to demonstrate the range of the field they could be applied. The first two analyze the use of design operators in design process and study their advantages. The third one refers to an overall use of DDF in design.

The first example is theoretical; it is a student master project in computation and architecture, which is directly related to the theoretical part of design operators and computation that was analyzed in the previous chapters. The second one, is an example of information managing; it has to do with an installation, the whole design and construction phase of which is described day by day through a blog from the chief architects. It refers to the personalization of a tool provided by a three-dimensional design program for the production of the desired result and also to the continuous amelioration of the designed object through models and constant controls. Lastly, the third example presents the whole design and construction process of a residential building in Switzerland, after its completion. Chief-architect’s comments in relation to the description transcript of the project process outline the image of DDF’s application in real practice conditions.

image 39: Fabrication operator (Pantazis E.)

image 40: photo from Chesa Futura (Foster Associates) with the village St Moritz in the background

image 42: photos of Tesselion (Skylar Tibbits)

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5.1.Rapid prototyping and fabrication operator/M. Dritsas, E. Pantazis This project constitutes an example of a general design operator creation that performs a process of direct prototyping. It has to do with a code capable of reproducing all necessary design information for the expression of every arbitrary surface to physical space. It was created by the author in rhinoscript and was based on previous work done by S. Dritsas, master student at MIT. The goal is two-fold; to confront complexity that the process of fabricating a digital designed surface model may create and to compress the time needed for the completion of this process. It constitutes an outstanding mechanism of negotiation between physical and digital design. The presented design problem, which is the fabrication of a double curved surface out of planar elements for the creation of a model as well as a design artefacts, helps us understand the phases of an operator development, the reasons that lead to its development and the importance of computation for design.

a) record every movement under specific conditions, b) produce a work program, explore the existence of parametric possibilities and in that way generalize specific parts of it.

An interesting ability of this way of coding a process is that it allows the direct location of all possible parametric points. All numeric information, for example, become immediately visible and could be parameterized.

This specific code takes as input every possible surface and a sequence of parameters. By analyzing the surface in curves that describe it in two vertical directions (isoparametric curves) it creates a curvy grid made of interconnected side parts over the surface. Then it reproduces the developement of its parts in a two-dimensional surface. These parts are sequentially numbered, coded by color and grouped. This process produces a design The goal was to describe all the necessary steps description suitable for further development with needed in order to produce one single model from a two-dimensional construction machine that is a surface, and afterwards by changing the constant every possible CNC machine. The completion of constraints of the process into controlling parame- this process takes few minutes, depending on the ters to be able to repeat the sequence with any ge- machine’s power. Executing the same process by neric initial input in order to create different design hand demands many hours. Therefore the advanoutcomes based on a given brief. This is a typical tage of selecting the coded process is based on implementation process of any automation favored time compression. operator: map down all actions under fixed-static By studying this coded process more carefully, it conditions, produce a working program and then becomes obvious that the computer executes a sefigure out where are potentials of parameterizing ries of geometrical computations, in a non Euclidthus generalizing the process exist (Dritsas, S., ian surface, that a typical user could not execute 2003). This constitutes a classic way of dealing with without the aid of the computer. This difficulty is not every operator that is under automation : the outcome of the “objective fact� that the user

image 43: digital models, coded outputs coming from a given surface with diferrent degrees of subdivision and marking of the intersections (knot).

is unable to copy the machine’s behavior. In every case the nature of automation secures that whatever the machine executes is the outcome of a coded behavior provided by the user. The key point of this process is the accuracy and stability of the results guaranteed by the machine, given an intact coded process.

Furthermore, apart some first technical advantages that such a technique ensures, such mechanisms cause interesting design process effects. For example, the fact that the digital design result, being trapped in its two-dimensional representation, could constitute a physical model for evaluation is obviously a more important result. Despite the fact that this evaluation is partial, as the model constitutes another design representation, its physical status allows a more tangible evaluation of the design concepts. The process of exploring possible ways to translate design in physical space is provocative, expressive and enables a richer design product.

are assigned to practical obstacles. For example, it is easy to imagine the in-between situations of two conditions, but it becomes impossible when these conditions increase. The revolution of the computational processes development lies in their ability to selectively produce samples of infinite combinations based on fractions of a series of possibilities that interject between multiple attractors.

Although this example is relatively restricted, it provides a lot of information on the ways one could handle such processes. Scale parameter is the next issue that comes on surface; a similar process, accordingly adjusted was used for furniture design production. In this updated application many actual factors were taken into consideration in the implementation of the design, such as for example the torsion possibility of the side elements that was “frozen� during the development process. Another arbitrary manipulation was the subdivision of the NURBS surface topology on a grid through the simplified use of the parameterization that every design The ability of reproducing multiple versions of a environment provides. Based on the gained experidesign form develops the traditional idea of design ence from the physical models this was enhanced evaluation through different simulations. Although in the actual designs. For the time being, one could the difference is quantitative, one may produce many argue that factors such as the above or the material models of the different design phases, it ends up properties could be embodied in the process and being qualitative. The classic evaluation process could provide more efficient results, either by solvand judgment of design alternatives is based on a ing the problems that may arise or by notifying the finite group of produced representations, sketches, user that the solution is impossible. However, given models, orthogonal projections, which are evaluated the restriced programming skills, that might also (for in comparison. Thus, we are used to select a small simpler applications) be too complicated to describe number of products, through a sequence, and to computationally that doing it intuitively. imagine the intermediate ones. Technically speaking, this is called interference. The process restrictions

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εικόνα 44(επάνω): image 44 (above):μοντέλο model επιπεδοποίησης for flattening theτου κόμβου και αναπαραγωγή του στον χώρο interlocking point εικόνα 45(αριστερά): καθορίσμός των του στον χώρο σημείων τομής των isoparametric και image 45(left): defining the crosscurves section παραμετροποίηση τους για έλεγχο επίand της points of the isoparametric curves ανάλυσης της επιφανείας. their paramtrization for control over the εικόνα 46(δεξιά): α,β)όλα τα στοιχεία της μακέτας analysis of the surface. κομμένα με laser, a,b)Laser γ,δ,ε)συναρμολόγηση των image 46(right): cut panels with στοιχείων και στ) διαφορετικές εκδοχές ( με βάση all the components nested c,d,e)assembly τονall βαθμό ανάλυσης τηςand επιφάνειας) of the components, f) alternative design outcome depending on the subdivision degrees of the surface.

Παρότι το πείραμαboth αυτόin είναι σχετικά περιορισμένο, This application smaller scale models as well προσφέρει πολλή τροφή γιαaimed τον χειρισμό τέτοιων as in 1:1 design objects to show that a coded διαδικασιών. Η παράμετρος της κλίμακας είναιbe το orgaprocess could be very flexible, as it could επόμενο που αναδύεται: μπορεί η ίδιαtoδιαδικασία nized in θέμα sequential steps from general specific. να Whenever χρησιμοποιηθεί a new factor για την is πραγματική revealed, παραγωγή the code has to του readjust σχεδίου. itself Στην rather συγκεκριμένη than rewrite εφαρμογή itself, so πολλοί as to paraπραγματικοί metrically include παράγοντες the new αφέθηκαν database. κατά μέρος, όπως για Forπαράδειγμα that reasonη the πιθανότητα same core στρέψης processes των πλευρικών could be στοιχείων. generalized, Αυτό soσυνεπάγεται as to cooperate πώς τοwith πρόπλασμά the production, μπορεί να theκατασκευαστεί available technology μόνο με κάποιο and the «ελαστικό» desired materials υλικό όπως that are χαρτόνι, introduced χαρτί, ήinto ένα the λεπτό process φύλλο μετάλλου. as databases. Η καναβική Thereforeυποδιαίρεση the only substantial της τοπολογίας difference μιας NURBS is the dataεπιφάνειας base’s size(εικόνα that has 45) to αποτέλεσε be coded, έναν that επίσης is the αυθαίρετο degree χειρισμό of detailμε that τηνwe απλοποιητική want the code χρήση toτης fulfill. κατεξοχήν παραμετροποίησης που κάνει το οποιοδήποτε σχεδιαστικό At περιβάλλον. this point, itΗbecomes αρχική αφελής obvious εκτέλεση that the πέρασε “design χωρίς εμπόδιο of design” ανάμεσα turns από out πολλά to be aρεαλιστικά really important προβλήματα. factor Για in such την ώρα, a process, μπορεί να a fact ειπωθεί thatπως was παράγοντές also mentioned όπως in το a previous υλικό, μπορούν chapter. να ενσωματωθούν It is the factor that στην determines πορεία της διαδικασίας to a great extent και να δώσουν the flexibility πιο αποδοτικά of the process. αποτελέσματα, This είτε λύνοντας τα προβλήματα που θα προκύψουν example serves as a good excuse to discuss είτε another ειδοποιώντας πως η λύση είναι αδύνατη. characteristicτον ofχρήστη digital design.

Until now we referred to the ability of digital design to “carry” construction information even from the early design phases, but we have never discussed the segmentation characteristics and abilities that it offers.

Η that, συγκεκριμένη πως διαδικασία By we implyεφαρμογή the total υπέδειξε ignorance ofμια some speκωδικοποιημένη κατά αυτόν τρόπο, μπορεί είναι cific factors of a problem in τον combination withνα the abπολύ ευέλικτη, μπορεί αυξητικά οργανώνεται straction of the καθώς medium, to the extentναthat it allows με examination βήματα από το στο ειδικό.without Με το που ένας to the ofγενικό real problems having deal νέοςwith παράγοντας the initialαποκαλύπτεται, and in-between ο κώδικάς frictions πρέπει with it.

For απλά a certain να αναπροσαρμοστεί period of time, παρά the να model’s ξαναγραφεί materiality εξ was αρχής, notέτσι an obstacle ώστε (παραμετρικά) for the code’s να συμπεριλάβει execution. On the contrary, την νέα βάση it provided δεδομένων. the possibility Για τον λόγο ofαυτό, reflection οι ίδιεςand production πυρηνικές διαδικασίες of specific μπορούν tangible να results. γενικευθούν What followed έτσι ώστε nextνα was συνεργάζονται the realization με την of the παραγωγή, next steps τη that were διαθέσιμη necessary τεχνολογία for theκαιspecification τα επιθυμητάof υλικά, the results. τα οποίαS. Dritsas εισέρχονται mentions: στη διαδικασία ως βάσεις δεδομένων.

“By Συνεπώς, the same η μόνη means ουσιαστική of scripting διαφορά it isείναι possible το μέγεθος to incorporate της βάσηςengineering πληροφοριών information που πρέπειeither να κωδικοποιηθεί, by encoding some ο βαθμός partial δηλαδή simulation λεπτομέρειας models που or by θέλουμε merelyκάθε plugging-in φορά να and εκπληρώνει adapting οaκώδικας. more credible Εδώ γίνεται openπροφανής and publicη engineering βαρύνουσα σημασία code-library. που αποκτά The meaning ο «σχεδιασμός of hacking του inσχεδιασμού» these termsσεrefers μια τέτοια to theδιαδικασία, potential όπως accessible προηγούμενα back-doors αναφέρθηκε. that Αυτός theκαθορίζει computation σε μεγάλο opensβαθμό to other και την fields ευελιξία of knowledge της to designers and to the possibilities for more information-dense designs.”(Dritsas S., 2003)

A level of abstraction between intentions and real considerations/conditions was always a very creative design factor. The difference in digital world is that allows many back and forth in this process.

With scripting is possible the direct embodiment of mechanic or static factors in design, either by coding some simulation models or by connecting the application with a reliable and open to public library of equivalent codes (of mechanics and statics). This example although not reaching that amount of programming complexity, proves that such embodiment of “realistic factors” can be introduced by the designer ‘s intuition or the fabricator’s experience in smaller scale projects whereas when nthe complexity rises they could be introduced computationallly.

Under this light, the concept of segmentation refers to possible alternative accesses from other fields that computation opens to architects and up until our days were segregated.

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images 46 (above left): photo of a bookselves design application image 47 (above right): photo of a coffee table design application image48 (opposite): photo of a conference table design application image 49 (above): photo of a light fixture design application

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5.2.Τesselion/ Philadelphia University Arch./ Skylar Tibbits/tutore: Fornes M., Yancone A. “Recently the development of planar quadrilateral meshes has become a strong interest in the architectural community due to their potential ease for constructing complex surfaces. The project responds to this problem and proposes a method for flat panelization of free form surfaces which provides large scale, efficient and economic construction from flat sheet material.” (www.tesselion.wordpress.com)

Tesselion is an installation placed at the department of architecture of Philadelphia University in June 2008. It is characterized by a relatively simple program that includes the roofing of a space and the creation of a seating place for its users. It’s a project that was based on the adjustment of a classic three-dimensional design program command (subdivide surface) for the development of a special design operator. This design operator manipulates the subdivision of complex, non regular surfaces in a panel system directly fabricated by a CNC machine. The aim is to simplify the fabrication of such forms, of relative large scale, and the creation of a spatial environment that is parameterized based on factors such as natural light and its programmatic adjustment. The form of the space emerges from the manipulation of these factors. Each panel could be unique due to the possibility of its digital production, while the development of coded parametric relationships allow for an emerging structural efficiency. The

optimization of the design result was based on material saving and construction efficiency.

In this example, one could clearly see that parameterization offered by digital design serves design’s readjustment depending on new inputs, while its connection to fabrication allows for multiple back and forth in a relationship in which simultaneously one feeds the other and vice versa. Through the “blog” that the architects created one could observe not only the elaboration of the project, but also the interesting design process.

image 50: photo (detail) Tesselion’s structure (Skylar Tibbits)

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5.2.1.Research

5.2.2.Form

Initially, after the definition of the program, architects decided to study a series of knots based on some criteria, such as: a) torsion resistance in two axis, b) panels dissociation/removal resistance, c) manipulation of construction’s structural integrity and certification of the necessary conditions for the construction to “curry” itself and d) production will be realized with a subtractive fabrication CNC three-axis machine, or with a laser-cutter machine.

These machines work with planar sheet material of specific dimensions. At the same time, a research on material was conducted based on the following criteria: weight/density, cost, and resistance. Aluminum was founded to be the most appropriate one.

The size of its cross-section was later decided, after being controlled on a physical model.

The installation’s form was based on three essential elements: a specific space in the university of Philadelpheia, where the installation was going to be placed, a given program and natural lighting. In the first stages, the range of tesselion’s capabilities on analyzing a surface was tested. According to the researchers the criteria to select a surface for analysis are subject to economic and time restrictions and also to certain small scale structural problems that may arise. Apart from that practically every surface could be analyzed with the design operator tesselion. This design operator is parameterized to the extent of surface analysis that is the number of panels on which a surface could be analyzed to.

Grater analysis means greater approximation of the non regular geometry and as a result more panels.

This parameter was an important factor in the specific project due to its financial effects. Apart from the surface analysis to individual panels, emphasis was given to the opening’s research. Their form and placement was based on environmental conditions (natural light) and also on simulations that were conducted in a digital environment.

images 51-54: renderings from design studies of the installation (above) image 55: rendering of the final proposal. (left page) image56: drawing of an unrolled panel and 2-3 assembly strategies image 57: construction drawing of connection with the ground image (above right) 58: foundation detail (above left)

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image 59 (from above to below): design& construction process a) renders from different design alternatives. b) renders of different possible connections c) force distribution (loads) diagrams and models of the connection point d) cardboard scaled model of the installation e) cutouts and assembled sheet metal mock-ups in 1:1 scale. f) on site construction

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image 60: photo of the installation’s upper part. image 61: photo overlooking the structure.

5.2.3.Design timeline During the project developement , which was not linear, multiple studies were designed and tested that had to do with the way the panels were connected and the form of their connections/knots. The design was tested both in physical and digital space. As time was passing the design model was informed, while after being tested through physical models and digital simulations (FEA control and torsion, bending, link controls) panels’ connections changed more than one time. The solution of having one panel with a folding blade that will function at the same time as a connection/knot was preferred to the use of an individual element as a connection/knot.

Part of the construction was tested three times for errors both at scale 1:1 (assembly of 6 panels) and through physical models of smaller scale. The creation of each model was followed by a reflection on design; record of its weak points, research of possible alternative solutions and direct update of the code with new data. This update has to do not only with design issues, such as the change of the connection/knot but also with practical issues, such as panel numbering and their appropriate placement to the available material panels, so as to save material. The development of the project study took three months. Through the blog one could follow day by day in detail the whole constructive process of updating the working model, as well as the continuous exchange of files and opinions between constructors and designers.

5.2.4.Realization After 3 months of continuous controls and attempts to optimize the design result the research team decided that the design was in a satisfactory level. For its fabrication they decided to use white aluminum of a 2mm cross-section. A total of 187 panels of a 20.3x10.2 cross-section cm were send to a laser cutter to be cut.

A necessary work at the location space involved the construction of the foundation that was made of metallic sticks and concrete, upon which the panels were assembled. The assembly of the construction, which involved panels’ folding and bolding, took seven days for one person who was working twelve hours per day.

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5.3.Chesa futura/ St. Moritz/ Switzerland/ Hugh Whitehead/ Foster and associates The project is a residential building in the tourist resort of St Moritz at Engadin valley at Switzerland Alps. The specific project combines the use of complex geometry and current construction technology It is an example that was studied and constructed by digital media. Architect’s reflection on the project, after its completion, makes clear the advantages of the specific working method. Furthermore, one could understand how a not very abnormal project of that scale could be materialized to the last detail.

The site is placed 1800m above sea’s altitude. The project is the amalgam of design tools of high technology and local traditional construction techniques that creates an environmental friendly building. It combines the application of environmental friendly traditional wood construction onto an innovative, pumpkin shape form. As Hugh Whitehead mentions “The bulding is raised off the ground on eight legs and has an unusual pumpkin-like form. This is a creative repsonse to the site, the local weather conditions and the planning regulations. The site has a height restriction of 15.5 m above its sloping contours. If the building were built directly on its sloping site, the first two levels would not have view over the existing buildings. Elevating the building provides views over the lake for all apratments and maintains the view of the village from the road behind the building. Raised buildings have a long architectural tradition in Switzerland-where snow lies on the

ground for many months of the year-avoiding the danger of wood rotting due to prolonged exposure to moisture.” (Kolarevic B., 2003) By sculpting the building into a rounded form, it responds the planning regulations. A conventional rectilinear building would protrude over the specified height.the limit. The decision not to introduce a use at the groundfloor as well as the first floo Because the ground and first floor are not utilized, the three elevated stories are widened to achieve the overall floor area, but do not appear bulky due to the building’s rounded form. The curved form allows windows to wrap around the facade providing panoramic views of the town and the lake.

image 62: photo of the Chesa Futura residential building 5 years after its completion

image 63: photo of the Chesa Futura pilotis

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5.3.1.Form development/finding

5.3.2.Construction strategy

The curve-like form was the result of the possibilities and the town planning restrictions of the site. The initial sketches and drawings were interpreted and formed in a three dimensional parametric model, which was then analyzed by the team in sub-reference-files so and thus the changes could happen in both directions (from the sub-files to the central file and vice versa). A parametric version of the section changed many times in several months, while at the same time it was informed by other design factors (mechanical, electronic etc).

The restrictions were such that a 2 degree rotation in design signified a 50m2 loss in plan, while a 2 degree rotation in section meant a 10cm decrease of the internal height of every level.

Due to the particularly hard climate conditions in the area during winter, construction work could carry out only six months per year. Thus, project’s timetable anticipated the construction of a metal grid with a concrete slab and then the pre-creation of the whole shell during winter, when it was impossible to work on site. Then during spring time, it would be possible to install the framework, the uplifted base, the columns and the roof and thus the shell could be completed and foreclosed before winter. Afterwards, the project would continue with interior work. This plan was the project’s construction strategy, which meant that the precise division of the work parts was of critical importance.

image 64: parametric cross section of the building image 65: diagrams of the developement and control of the skin and the building’s overall form image 66: perspective section ans rendering of the interior image 67: stuctural scaled model of the building. (from left to right)

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5.3.3.Database management strategy For rational design organization, the idea of comparing plan with section was explored in an eminently design way, reproducing nonetheless possible construction solutions with the use of small applications, known as macros. These macros operated as a “ruler” that was controlled by a polar coordination system. The ruler scanned plan’s sectors and lists measurements, which were then projected onto the corresponding lines in section. Subsequently, it produced a series of parameters, which were embodied in a based on restrictions wall section. As a result the wall was obliged to adjust itself to the corresponding shell positions. The specific macro had a dual function: it could either produce a solid model of the shell surface, with the connected parts of its structural framework, or to produce a table with multiple drawings that could be used for further detail drawings production. As the project was developing, every member of the group was responsible for a different parameter set that related to the thickness of the used materials. One group member could

work on the roof, another one was responsible for the structural framework, a third-one dealt with the zone of shell-columns, surface-layering and fire protection, while a fourth-one controlled the openings and window details. Having access to the same parametric file, allowed the group not only to respond to each design direction but also to coordinate the project’s process.

At the same time every sub-group was making the necessary changes as a response to other sub-group changes.

The whole digital model geometry was based on circular arcs. The programming of the pre-construction demanded a digital model that could lead advanced CNC machines to a German factory, in precise mechanical durability. The chief-architect mentions that “to successfully use these machines, we should understand the modeling process in relation to its mathematical translation. Although the surface has characteristics of a free form curve, it is analyzed in individual normal

image 68: exterior view of the building, handmade production of the wooden roof tiles from a local carpenter, digital fabrication of the structural beams

surfaces that have their routes in circular arcs that perfectly osculate.”

the surface that was given to the engineers to work on and solve.

The analyzed surfaces are ideal for the process of solid core modeling, as the software could directly compute the counterbalances and produce accurate and clear results, a fact that is very important during an intense design activity. The ability of producing direct and reliable computation without having software (CAD) errors allowed the continuous exchange of digital models with Swiss project engineers and German constructors (Amann). Design group’s decision to rationalize the shell-surface, by analyzing it in circular arcs, provided a degree of control that helped not only to simplify but also to solve many design and construction problems.

The limited command range (macros) that were developed could calculate all circular arcs, on the basis of construction prescriptions and then could place them in space, by reproducing automatically the shell, the framework and all individual three-dimensional parts, based on the parametric values of each relocation. The result was a precisely defined shell, which constituted

Hugh Whitehead mentions that “At this point we made a commitment to make no further alterations to the design surface ,although offsets were continually varied throughout the year as the project evolved. We could locate any component by choosing a position on the polar grid, creating a plane, and intersecting with the design surface to determine the radial offset for placing the component. In addition to being able to accurately model and place components in space, we could generate a matrix of sections, drawn for each rib position and thus produce templates for all shop drawings”

image 69: perspective cross section of the openings

When the plan and section had to be changed, even at the latest project phases, the group could reproduce the shell-surface in a cohesive and reliable way. This design process, based on some programming materials, had been developed to the extent that it was a more spiral rather than a linear process. The freedom of exploring multiple alterations of a design was proved

image 70: perspective section of the building’s interior

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to be the key point of optimization.

5.3.4.Assembly strategy Hugh Whitehead mentions, ” In the Foster studio, most of the key design descisions are still made from the study of physical models. In fact, the CAD system was introduced initially to the studio to provide shop drawings for our model makers.”

With the use of digital technology a project could start from three-dimensional digital models and then send in the model lab to be fabricated with CNC machine. There is a constant dialogue between drawings, digital models and physical models. A typical project meeting includes all possible media – sketches, digital models, renders, physical models made out with CNC as well as rough physical models.

Chesa Futura’s next model generation was based on actual structural elements and was designed in a way to exactly control building’s assembly process, as the construction firm Arup envisioned and the Swiss technical company Toscano developed. This model contained everything, starting with the metallic framework with the uplifted lower part, the concrete slab, the side carrier parts and the columns of C profile of the front balconies and finally the circular roof disk. This corresponds to the initial level that was used to define the surface, which was signified by a slopped rut that indicated material change from the side wall to the roof. All windows are similar and double, so as to be efficient in the extreme climate conditions. The openings on every window façade are different and made individually, but the financial profit of using one type of window-frame is a lot higher.

Every digital model generation was leading to the next physical model generation, as a greater degree of detail was explored. At this point they had to study the control technique of the wooden surface, which was made out of thin boards, in relation to the window openings. The representation of the surface at this scale demanded a physical model of high accuracy. A surface diagram was created in the digital model, which showed how the surface would be analyzed to the boards. Their size is decisive for the development of the in situ installation. The boards were represented by slices of colored graven brazen that were applied on the surface. Due to the model’s great degree of detail the group was in position to locate all the key points for the in situ assembly as well as to discuss some details with the workers that were about to construct the boards.

At the time of industrial fabrication, the side carrier elements were made with CNC machines from agglutinated wood timber, an extraordinary material that combines the resistance of steel, the ductility

image 71: combination of section and floor plan and the the translation image 72: photo of the skin in relation to its context

image 73: exploded axonometric of the BIM image 74:Building infromation model’s components : a) the metallic slab and the hanging lower part, b) the conrete slab, the side structure and the frontal balconies, c) addition of wall panels and of circular rings, d) assembled stucture with all its components το ( from top to down)

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5.3.5.Model in 1:1 scale of concrete, the levity of wood and has exceptional capacities. Amann constructors specialize in the production of structural beams with multiple agglutinated leafages.

Since the frame was digitally designed and fabricated so as to achieve materials’ mechanical resistance, it sounded ironic to cover it by thin boards that a local eighty year old artisan constructed with an ax. Then the thin boards were riveted by the rest of his family.

The last model generation was now informed with data concerning the armos between the finishes. At this point the presentation of perspective detail sections (using the technique of hidden lines appearance) was very helpful. These representations successfully achieve to communicate the information not only for the assembly, but also for the final look of some important points.

image 75: view of the building from the village

The detailed final digital model was tested with the construction of a typical building part in 1:1 scale. It was constituted from a window, its pareies and the carrier side elements. The real size model was constructed in site and was a critical point of the project as everybody was then convinced that the construction of the building was possible. The construction’s development showed how a building of such peculiar form could adjust so well to the physical environment.

Although the building’s veneer was created with thin boards, traditional of the Alps architecture, the high technological structural frame that holds them justifies the project’s name, Chesa Future, which means the house of the future.

5.3.6.Development Hugh Whitehead states “ Through the experience of City Hall we learned the importance of being able to postrationalize building geometry. In the case of the Chesa Futura, we were able to embed the rationale in the tools used to create the form. The developement of customized utilities is now based on a function library, which extends with every project undertaken and is structured to allow functions to be combined by the user without having to prescribe the workflow.”

Finally, it is worth telling that most architects have been educated in programmed thinking. Despite this fact having neither the time nor the tendency to develop programming abilities they don’t acquire the media to express or explore such a way of thinking. Mentally, designers have long over passed CAD software that mainly contain systems for structural, affinity and time descriptions. What is needed is some time for adaption and familiarity with the specific peculiarities of the new medium, a fact that always follows the introduction of a new condition.

image 76: view of the building in its context with the Alps in the background

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6.[Summary]

6.1.Conclusions In digital design fabrication the harmonious relationship between design and fabrication, which could be achieved with the use of digital media, offers an important opportunity of reconsidering these processes in architectural field. Their intense application nowadays makes this ability easier to understand. the introduction of digital fabrication, given the fact of the wide use of digital design (CAD environments) even in a limited way, ensures at least a better communication between these two phases. This direct communication assures error prevention, which many times arises from the obliged translations between analogue and digital and vice versa. This was happening routinely the past few years due to the lag between design and fabrication technology.

Products that were designed with the aid of updated programming environments were fabricated with old techniques that were stationary the past years. In many cases, this disagreement was hidden, judging from the result. This, of course, does not mean that it was absent from the process.

The embodiment of CNC machines constitutes the first step for bridging the gap between digital design and construction as it restores part of this communication circle. Better understanding of design

software and the development of programming abilities, aiming at the at will adjustment of these environments constitutes the piece that closes this circle. Code and macro commands’ writing, for the creation and manipulation of design operators in a digital environment, would not be an exaggeration to be parallelized to the development of abilities in the use of pencil and paper in the physical environment.

Undoubtedly, we should deeply examine the meaning of introducing DDF (digital design fabrication) in architecture. Apart from harmonically unifying design and fabrication, DDF has some important financial benefits. As Bernhard Franken informs us, many times architecture produced with a DDF process costs less than a conventional building construction.

For example, in Frankfurt’s 2001 International Exhibition, BMW’s “Dynaform” pavilion that was fabricated based on DDF techniques cost one third less per square meter than the corresponding ortho-regularly and conventionally constructed pavilion of “MINI” that was sponsored by the same company. Furthermore, DDF’s introduction in architecture presents the important challenge of mixing together many practices that until recently were separate. In these observations one should add the experimental at-

image 77: Photo from the of Μuscle Tower at TU Delft (TU Delft)

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tempts in the field of IA/interactive architecture/swarm architecture ( Verb, Natures, 2006). This field examines how the use of DDF and other sciences could help us expand our understanding of architecture and space.

It studies adjustable to the outer conditions facade constructions. Additionally, it examines the fabrication of light sensitive roofs, which open and close depending on the space’s solar radiation, and the structure of which change depending on the use. Such applications no longer exist as science fiction but are actually realized as pilot programs. A brilliant example is the Muscle Tower that was presented in Aandrijftechniek exhibition during industrial design week, in the Netherlands in 2004. It is a structural construction model in 1:20 scale that interacts with the interior (users) and exterior (climate) conditions and behaves respectively. In any case, one should consider whether the introduction of this method actually provides a solution in complicated problems or simply produces complicated solutions for simple problems.

parameters (relations, influences, constrains, rules) that are introduced as data. Architects choose from a group of results that they control. These results undergo further changes based on other parameters (material constraints) and produce new ones. The process is developing in a spiral form and stops whenever the architect decides it to. There are multiple benefits, as continuous process information is encouraged, while it is methodically led to a clearly coded and parameterized target.

Key point of this process is the group of parameters that are set for its control (the results’ unpredictability, due to the computations that are involved in the process, constitutes for many people the digital translation of the creation. Non linearity, “exact” vagueness and emersion are legitimate conditions.)

The easy regression both from one stage of design to another and from design to fabrication constitutes an important advantage. The classical deterministic model of a linear architectural production has been set aside.

Architects are now asked to design and code a productive rule system that is being controlled from a group of

6.1.Experiments It is a well known fact that every tool originates from a culture and has to serve it. At the same time this tool produces a new culture that is not always distinct and often gets by unnoticeable. The introduction, though, of a new tool does not necessarily mean the abandonment of the previous ones but on the contrary demands their combination so as to attain the best result. This fact is obvious in the example of Chesa Futura, where current and traditional techniques are combined in a way that one could not distinguish one technique from the other.

The application of digital design and fabrication techniques does not exclude previous working techniques, but on the contrary it seems to be fed by them. Critique on DDF, though, based on arguments extracted from traditional ways of working is rather absurd and leads to a dead-end.

A first step towards the application of digital design and fabrication techniques was done with the further elaboration on the design operators’ concept developed by S. Dritsas (Dritsas S.2004) and with the developement of an own script (RVB script) for the realisation of double-curve surfaces out of interlocking flat elements. This concept will be further tested by the final design and production of a furniture series.

A second experiment for future research will include a study on fully constrained motions. We will focus on one particular case, that of Bennet Linakge (image 78) and we will attempt design a environment responsive (kinetic) design artefact.We will attempt to prove the above conclusions by implementing digitally from one side the design and the fabrication and the behavior on the other side of such an artefact based on a given set of operators (Grasshoper. Rhino) and fabrication technologies (laser cutter).

image 78: study on Bennett linkage (render)

“The fascinating thing about technology is once you have a sense of what it can do it fills the imagination. I am sort of a hopeless case of being like a monkey with a stick poking into an anthill. But one realizes that the essence of technology is not the stick-the stick is ust a stick- it is in the desire for ants that propitiates. This is the real point at issue for a cultural descourse� dECOi /Goulthorpe,M.,(Kolarevic, B., 2003)

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[Bibliography] Actar/ Verb: Architecture Boogazine/ issue Natures/ Barcelona, Sp/ Actar press, 2006/ .Copeland, B.J/ «The modern history of Computing»/ The Stanford Encyclopedia of Philosophy (Spring 2001 Edition) / Edward N. Zalta (ed.)/ 20 April 2000/ URL= http://plato.stanford.edu/archives/spr2001/entries/computing-history/ . Dritsas, S. / “Design operators” / Master of Science Thesis, Massachussetts Institute of Technology, MIT University/Cambridge/ MA: MIT,2004/ . Eastman, C M / “Building product models: computer enviroments supporting design and construction”/ Boca Raton, FL/ CRC Press, 1999/ .Kolarevic, B, ed./ “Architecture in the digital age-design and manufacturing”/ Abdignon / Taylor and Francis group,2003/ .Meredith M./ “never enough,in the from control to design”/ ed. Sakamoto, T., Ferre A./Barcelona/ Actar press, 2007/ .Mitchell W.J/ «the logic of Architecture: Design, Computation and Cognition»/ Massachussetts Institute of Technology MIT University/Cambridge, MA: MIT/ MIT Press,1990/ .Mitchell, W.J., McCullough/ “Protoyping” (chapter 18) in Digital Design Media, 2nd edition/ New York/ Van Nostrand Reinhold,1995/ .Pantazi Magdalini-Eleni/ “Dissecting Design: Exploring the Role of Rules in the Design Process”/ Master of Science Thesis, Massachussetts Institute of Technology, MIT University/Cambridge/ MA: MIT,2008/ . Saas, L., Botha, M./ “the instant house: A Model of Design Production with Digital Fabrication”/ international journal of architectural computation/issue 04,volume 04/ 2001/ . Saas, L. / “Materalising Design: the implications of rapid prototyping in digital design”/ Massachussetts Institute of Technolog MIT University/Cambridge/ MA: MIT,2008/ .Sakamoto T, Ferre Albert, ed./ “from control to design”/ Barcelona, SP/ Actar Press, 2007/ . Tεγοπουλος , Φυτράκης/ “Μείζον Ελληνικό Λεξικό”/ Αθήνα, Ελλαδά/ εκδόσεις Τεγόπουλος-Φυτράκης.

2008/ . Terzidis, K./ “Algorithmic architecture”/ Massachussetts Institute of Technology MIT University/Cam bridge,[βιβλιογραφία] MA: MIT./ Architectural press,2001/ .Tesselion: Adaptive Quadrilateral Flat Panelization/ Tibbits Skylar, Philadelpheia, 20 May 2008/ http://tesselion.wordpress.com/

[image index] Kolarevic Branko, (2003), “Architecture in the digital agedesign and manufacturing” ,pg. 94-100 εικόνες (03,14,19,27,28,32) Verb: Architecture Boogazine, (2006), issue Natures, pg. 42-45, 54-64,(images: 01,07-09,13.14) author’s archive (images: 02,04-06,67) Saas lary (images: 29,30,33) -case study images .rapid prototyping and fabrication operator: Dritsas Stylianos (pg 35,38-42) .Tesselion: Skylar Tibits (images37, 43-53) .Chesa Futura: Kolarevic Branko, (2003), “Architecture in the digital age-design and manufacturing” ,(images 55-66) wikipedia (images: 20-26,34) flickr.com (images: 36,54,65,66) -images from the internet http://tesselion.wordpress.com/, access on στις 15/06/2009 http://flickr.com/, access on 15/06/2009 http://wikipedia.org

[Acknoledgements] At first, I would like to express my gratitude to Stavros Vergopoulos, the supervisor professor of this dissertation project , whose help and useful guidance were of significant importance in thedevelopment of this research.

I would like to also thank my friend Schina Kostas as well as my sister and architect Pantazi Magdalena for their interest and felicitous comments on my writings. Their help was determining in the development and proper expression of my realm of thought.

I am grateful to my friend Gkogka Vic-Symbolink- for his comments on the graphic layout of this publication. Moreover a big thanks to Kosta Sfika for letting me use his laser cutter and thus allowing coming into contact with digital fabrication and testing some ideas in real.

I would like to thank all my colleagues at 101&107 ‘kamarakia’ (diploma-classrooms) at AUTH university, for being always willing to share thoughts and discuss the subject from different perspectives, but also for their tendency to act and react collectively.

Last but not least, a big thanks for my parents and architects Pantazi Spyro and Margaritidou Eleni, for their help and support of my studies and ventures as well as my brother Pantazi Iason for his advice and rich insight.

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/BDDF-09/ /Bridging Digitally Design&Fabrication /AUTH, Greece, June 2009 /student: Pantazis Evangelos /Supervisor: Vergopoulos Stavros