Digital technologies are changing the way we live today from our interactions with people to how we work and be entertained. Architectural practices have progressed and revolutionised their work methods and services in ways that few were able to anticipate just a decade ago. The most obvious yet intrinsic aspect being the jump from drawing board to the computer, which can be seen from architectural teaching right through to everyday practice. Indeed the computer has revolutionised the output ability and flexibility of editing and changing ideas and designs. However, digital technologies have affected the practice of architecture in much more deeper ways.
�Architecture continually informs and is informed by its modes of representation and construction, perhaps never more so than now, when digital media and emerging technologies are rapidly expanding what we conceive to be formally, spatially, and materially possible� 2
The basic argument is that the digital age is forging a very different kind of architecture and at the same time providing unprecedented opportunities for significant redefinition of the architect�s role in the production of buildings. Digital technologies are enabling a direct correlation between what can be designed and what can be built, thus bringing to the forefront the issues of production, communication, application and control of information in the building industry.
In the conceptual realm, computational, digital architectures of topological, non- Euclidean geometric space, kinetic and dynamic systems, genetic algorithms are supplanting technological architectures. Digitally driven design processes characterised by open ended and unpredictable but consistent transformations of three-dimensional shapes are giving rise to new architectonic possibilities. The generative and creative potential of digital media, together with manufacturing advances already obtained in automotive, aerospace and product design is opening up new dimensions in architectural design.3
Digitally informed practice has included many generations of designers since its arrival in the early 1990�s, so it�s not new to the discourse of architecture, and has a history. In reviewing the history of work in this field, and the level of technological development and the quality of the constructed work cannot be separated. As techniques are further refined and improved, so has the quality of the fabricated work and its aesthetic sensibility. Looking at the different techniques and technologies available helps highlight the impact these have on architecture as a whole and individuals work process. In this essay I want to explore the various computer based processes of form origination and transformations using examples of various architects work.
�Integrating computer-aided design with computer-aided fabrication and construction fundamentally redefines the relationship between designing and producing. It eliminates many geometric constraints imposed by traditional drawing and production processes� making complex curved shapes much easier to handle, for example, and reducing dependence on standard, mass-produced components. It bridges the gap between designing and producing that opened up when designers began to make drawings.� 4
�Architecture is recasting itself, becoming in part an experimental investigation of topological geometries, partly a computational orchestration of robotic material production and partly a generative, kinematic sculpting of space�5
In Greg lynns essay �architectural that is curvilinear�6 he highlights the new approaches to design that move away from the deconstructive �logic of conflict and contradiction� to develop a �more fluid logic of connectivity.� This is manifested through folding that departs from Euclidean geometry of discrete volumes, and employs topological, �rubber-sheet� geometry of continuous curves and surfaces.�
In topological space, geometry is represented by parametric functions, which allow for a range of possibilities. The continuous, highly curvilinear surfaces are mathematically described as NURBS � Non-Uniform Rational B-Splines. Nurbs allow representation of geometrical shapes in an easily edited form. Whilst handled by computer programs they allow for easy interaction by the user. NURBS surfaces are functions of two parameters mapping to a surface in three-dimensional space. The control points determine the shape of the surface with the polygors responding to the adjustments automatically. The image below illustrates the typical Nurb interface.
?Figure 1 - Example of Nurb interface
Breaking away from the rectilinear straight angled forms is highly associated with digital architecture thanks to the ability to specify and calculate dense mathematics easily. It gave architects an instant visualisation of their ideas and allowed for specific alterations to be implemented without having to re asses their initial ideas.
One of the most prominant examples of this is Frank Gehry�s Guggenheim Museum in Bilbao. The building is uniquely a product of the Computer Aided Three Dimensional Interactive Application (CATIA) and visualizations were used heavily in the structure's design. Computer simulations of the building's structure made it feasible to build shapes that architects of earlier eras would have found nearly impossible to construct. Gehry is seen to be at the forefront of Topological space design and as a poster child for the use of technology in building design.
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Fig 1 - Guggenheim Museum in Bilbao by Frank Gehry
Blobs or Metaballs are a technique invented by Jim Blinn in the 1980�s. They are also known as isomorphic surfaces, they are seen as amorphous objects constructed as composite assemblages of mutually inflecting parametric objects with internal forces of mass and attraction. They exercise fields or regions of influence, which could be additive or subtractive. The geometry is constructed by computing a surface at which the composite field has the same intensity: isomorphic surfaces. These open up another formal universe where forms may undergo variations giving rise to new possibilities. Objects interact with each other instead of just occupying space; they become connected through logic where the whole is always open to variation as new blobs (fields of influence) are added or new relations made, creating new possibilities. Objects can then behave in a dynamic free form way rather than a static assembly.
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Fig 2 - Metablob behaviour diagram
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Fig 3 - BMW�s �The Bubble� exhibition pavillion at the IAA 99 Auto Show Frankfurt
Another common digital design process is Motion kinematics & Dynamics (animate architectures). Animation software is utilized as medium of form-generation. Animate design is defined by the co-presence of motion and force at the moment of formal conception. Force, as an initial condition, becomes the cause of both motion and particular inflections of a form. While motion implies movement and action, animation implies evolution of a form and its shaping forces. The repertoires of motion-based modelling techniques are key frame animation, forward and inverse kinematics, dynamics (force fields) and particle emission. Kinematics are used in their true mechanical meaning to study the motion of an object or a hierarchical system of objects without consideration given to its mass or the forces acting on it. As motion is applied, transformations occur down the hierarchy in forward kinematics, and up through hierarchy in inverse kinematics.
Fig 4 - Port Authority Bus Terminal in NY by Greg Lynn
Dynamic simulations take into consideration the effects of forces on the motion of an object or a system of objects, especially of forces that do not originate within the system itself. Physical properties of objects, such as mass (density), elasticity, static and kinetic friction (or roughness), are defined. Forces of gravity, wind, or vortex are applied, collision detection and obstacles (deflectors) are specified, and dynamic simulation computed. Allowing the designer to guage the effects of the world around his design is key here simulating the built form in reality whilst still being in the design stage.
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Fig 5 - Tea Set for Alessi by Greg Lynn
With the software available now it allows designers to adapt and further explore the customary standard shapes associated with the built environment it opens up the possibilites of shapes and their effect on design in general. Metamorphic generation of form includes several techniques such as keyshape animation, deformations of the modelling space around the model using a bounding box (lattice deformation), a spline curve, or one of the coordinate system axis or planes, and path animation, which deforms an object as it moves along a selected path. In keyshape animation, the changes in the geometry are recorded as individual spaced out keyframes and the software then works out the formation in between these. In deformations of the modelling space, object shapes conform to the changes in the overall geometry within the space rather than the reforming of the individual shape.
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Fig 6 - Ustra Office building (1999), Hanover, Germany, Frank Gehry
The twist seen in Gehrys design can be attributed to a fourth dimension used in the program during the design. The twist in the building to point towards the nearby park skews the common rectangular shape whilst allowing more people views of the park. Calculating the curvature and resulting effects on the overall design would have been automated through the sue of the software package.
Parametric design is the process where the
rather than the overall shape of the design being allocated. The different value parameters and configurations along with mathematical equations define the objects and their proximity to each other. This allows the objects behaviour to other objects and their transformations to be quickly edited and proofed. Ultimately the designer can scroll through many variations of the same design quickly and decide on the best overall design that works well with other defined objects. Mathematical software can be used by the architect to design mathematical models to automate test procedures on the design using different slots to test varying external forces and influences both static and dynamic in nature. Essentially this automated type of design lessens the intensity of the designers input filling in the blanks over the period of the parameter designated.
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Fig 7 - The Jellyfish House - Iwamoto Scott architects
The tiling shown above in the jellyfish house was processed with parametric software allowing the overall geometry of the building to be processed to varying degrees as designated the user. Designers can go as far as to fully automate the parametric design process and allow the computer to create the geometry automatically resulting in random and complexly unique shapes and constructions.
Evolutionary architecture proposes the evolutionary model of nature as the generating process for architectural form. Architectural concepts are expressed as generative rules so that their evolution and development can be accelerated and tested by the use of computer models. Concepts are described in a genetic language, which produces a code script of instructions for form generation. Computer models are used to simulate the development of prototypical forms, which are then evaluated on the basis of their performance in a simulated environment.
Very large numbers of evolutionary steps can be generated in a short space of time and the emergent forms are often unexpected. The key concept behind evolutionary architecture is that of the genetic algorithm. The key characteristic is a � string-like structure equivalent to the chromosomes of nature,� to which the rules of reproduction, gene crossover, and mutation are applied. Optimum solutions are obtained by small incremental changes over several generations.
Fig 7 - Kolatan and Mac Donalds �Chimerical Housing projects�
�In housings a normative 3 bedroom colonial house was used as a �base� object that was then morphed into a range of everyday objects as �targets�, producing a large range of what they call �chimerical designs��7. The technique of morphing and skewing the normal reality of an object or building through computer manipulation allows easy access to a huge range of design variations but also the evolution of a design. Asking the question where would this design have went if it wasn't finalised by the designer.
It was only within the last few years that the advances in computer-aided design (CAD) and computer-aided manufacturing (CAM) technologies have started to have an impact on building design and construction practices. They opened up new opportunities by allowing production and construction of very complex forms that were until recently very difficult and expensive to design, produce, and assemble using traditional construction technologies. The consequences will be profound, as the historic relationship between architecture and its means of production is increasingly being challenged by new digitally driven processes of design, fabrication and construction.
Digital architectural fabrication refers to the computationally based processes of form production and fabrication based on a digital architectural model. Several digital fabrication processes are identified based on the underlying computational concepts such as:
CNC also know as computer numerically controlled cutting / 2d fabrication is at the heart of modern fabrication. These vary vastly depending on the techniques and materials being cut with laser and water jet being the most widely used format. What they all share is the ability to submit CAD drawings to allow very precise and specific cutting on various materials. In the construction industry highly specialised machines such as plasma arc cutting wherein an electrical current is passed through pressurised gas resulting in plasma that can burn up to (25,00f) allowing for heavy duty yet highly precise cutting.
Laser-cutters use a high intensity focused beam of infrared light in combination with a jet of highly pressurized gas (carbon dioxide) to melt or burn the material that is being cut. There are, however, large differences between these technologies in the kinds of materials or maximum thicknesses that could be cut. Laser-cutters can cut only materials that can absorb light energy; water-jets can cut almost any material. Laser-cutters can cost-effectively cut material up to 5/8�, while water-jets can cut much thicker materials, for example, up to 15� thick titanium. In 2D fabrication there are many different variations including contouring, triangulation, developable surfaces, and unfolding. They all involve extraction of two-dimensional, planar components from geometrically the differing surfaces or solids comprising the building�s form.
Subtractive fabrication has recently been increasingly popular in the construction industry as a very specific way of creating formwork for intricate casts. CNC milling involves the subtraction of volumes of material from designated solids. The computer controls the movement of the cutting mill when coded instructions are submitted based on the sheet size of the material. This technique has been used by Gehry in both his Office building in Dusseldorf and for glass panels in his Conde Nast Cafeteria project .
?Fig 8 - Plasma-arc CNC cutting of steel supports for masonry walls in Frank Gehry�s Zollhoff Towers in D�sseldorf
The opposite of subtractive fabrication involves a gradual forming achieved through the addition of the material step-by-step on top of each other. This layering technique known as additive fabrication or more commonly rapid prototyping revolutionised product design from the ground up. The computer model is sliced into two-dimensional layers; the information of each layer is then transferred to the manufacturing machine and the physical product is generated in a layer-by-layer way. The models can be made from a huge range of plastics and plasters. However architects are now turning to it as a quick alternative to hand crafted models allowing the exportation of 2d plans that can be quickly layer by layer mad into a fully formed scale model. Although costly this technique allows the architect to quickly be able to pick up their design rather than view a floating 3d computer model.
A number of competing technologies now exist on the market, utilizing a variety of materials and a range of curing processes based on light, heat, or chemicals: Stereo lithography (SLA) is based on liquid polymers, which solidify when exposed to laser light. Selective Laser Sintering (SLS) laser beam melts the layer of metal powder to create solid objects.
In 3D Printing (3DP) layers of ceramic powder are glued to form objects. Sheets of material (paper, plastic) either pre-cut or on a roll, are glued (laminated) together and laser cut in the Laminated Object Manufacture (LOM) process. In Fused Deposition Modelling (FDM) each cross section is produced by melting a plastic sheets that solidifiy upon cooling.
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Fig 9 - Typical 3D Printer
Multi-jet manufacture (MJM) uses a modified printing head to deposit melted thermoplastic/wax material in very thin layers, one layer at a time, to create three-dimensional solids. Sprayed concrete were introduced to manufacture large-scale building components directly from digital data.
In formative fabrication mechanical forces, restricting forms, heat, or steam are applied on a material so as to form it into the desired shape through reshaping or deformation, which can be axially or surface constrained. For example, the reshaped material may be deformed permanently by such processes as stressing metal past the elastic limit, heating metal then bending it while it is in a softened state, steam-bending boards, etc. Double curved, compound surfaces can be approximated by arrays of height-adjustable, numerically-controlled pins, which could be used for the production of moulded glass and plastic sheets and for curved stamped metal. Plane curves can be fabricated by numerically controlled bending of thin rods, tubes, or strips of elastic material, such as steel or wood, as was done for one of the exhibition pavilions designed by Bernard Franken for BMW.
�The idea of a structural skin not only implies a new material, but also geometries, such as curves and folds that would enable the continuous skin to act structurally, obviating an independent static system: The skin alone does the heavy lifting.� 8
Construction itself is rapidly changing due to technological advances, which are no longer confined, to the fabrication stage. Upon fabrication of components virtual 3d models are often used to pinpoint the location of each highly specialise item created. Even on my year out experience technology such as laser measurement and electronic surveying where common. A large-scale example being Frank Gehrys Bilbao museum where the construction was like a paint by numbers experience. Most components where bar-coded and scanned to locate the precise location.
Whilst mass production for standard building components became common decades ago the need for huge amounts if detailed and irregular building components became possible with CNC techniques. Systematic customisation allowed architects to make large buildings unique over the desired space without resorting to standard building components or spending huge amounts on individual craftsmanship across the build. With CNC it is just as efficient to make the same design as it is to make 100 different designs with the drawing work being the only time consuming factor.
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Fig 10 - Mass Customization: Bernard Cache�s �Objectiles�
The question we are now faced with is what is the architectural language of the future going to be? We have witnessed a gradual shift from hand drawing to the computer this century; digital design students of all fields have the potential to be the pioneers of new methods of designing within the virtual world.
�The new generation of students have skills in video, web design, animation and interactive multimedia. They are using 3d design as a real working environment for inventing form and space. That is their new habitat.�9
These advance in technology and applications to architecture do not only affect the high-end firms and rich users but instead are trickling down to the students starting out in the field. The emerging architectural language is directly linked with the new tools studied above. These technologies take us directly from the mass used 3D world to the built form. Taking an Idea from concept to physical form is easier than ever with the current tools, which allows for more experimentation and diverse ideas.
�The computer has gone from being an isolated box to become part of a gigantic digital network of networks, which shapes our collective future. The way and pace at which we connect, communicate, memorize, imagine and control the flows of valuable information have changed forever.� 10
This advancement is not without repercussions as the technical vocabulary of the new design student is alienating them from those not as familiar with the ever changing technological advancements. Using terms such as NURBS (Non-Uniform Rational B-Splines) mentioned above can mean that the young architect leapfrogs the elders into new areas. These new terms and skills replace older skills the most evident of all being hand drawing. Sketching is still an integral part of a designer�s life but hand drawing final proposals is a thing of the past mainly due to time limits and accuracy available to everyone.
�Architecture is presently engaged in an impatient search for solutions to critical questions about the nature and the identity of the discipline, and digital technology is a key agent for prevailing innovations in architecture. Although, this is really nothing new, as new technology has always been a catalyst for new ideas in architecture. A positive digital future in architecture requires a clearer definition of principles and skills necessary to maintain a rigor in emerging digital projects.� 11
Opinions vary on the benefit of the technologies currently on hand for new skills being taught at university enable students to focus on the design rather than the solely the labour of drawing everything by hand .The computational architectures described necessitate certain design strategies that provide for a dynamic manipulation of the designs with a high degree of indeterminacy. The future of digital architecture rests on the extent to which architects can accept that exemplary architectural designs can be created in a computer- mediated environment and that digital thinking is indeed architectural thinking.
� There�s a nostalgia for a time when there was technological optimism, when people felt like the world would be a better place with technology, that�s almost completely gone from our culture, and I think that�s really sad.� 12
In the chilling words of Frank Lloyd Wright
�If it keeps up, man will atrophy all his limbs but the push-button finger.�
(Frank Lloyd Wright)
