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[ PARAMETRIC MODELLING ]

Woodbury, Robert (2010). Elements of Parametric Design (London: Routledge) pp. 7-48

Woodbury, Robert F. and Andrew L. Burrow (2006). ‘Whither design space?’, Artificial Intelligence for Engineering Design, Analysis and Manufacturing, 20, 2, pp. 63-82

Kolarevic, Branko, Architecture in the Digital Age: Design and Manufacturing (New York; London: Spon Press, 2003) Sug-gested start with pp. 3-62

Kareem El Sayed Mohammad, A Discussion on the implications of parametric thinking on the Design process and the Designer (2012)http://www.academia.edu/1454680/A_Discussion_on_the_implications_of_Parametric_thinking_on_the_design_pro-cess_and_the_designer

New digital advancement in digital technologies within the architectural domain has developed a new generative approach, that of parametric modelling. Such approach develops in the architect new conceptual design thinking which makes the designer to focus more on the concept and logic behind the design. Branko Kolarevic stated that architects are not designing the specific shape of the building set but a set of principles encoded as a sequence of parametric equations by which instances of the design can be generated and varied in time as needed. Woodburry attributed the potentiality and the designer’s ability to explore more ideas to the fact that the system keeps the design consistent with relationships which reduce the tedium of rework.

On the other hand, some CAD programs works with the parameters of the standard geometric shapes already found in the libraries of the software. These can offer a limited use of the potential of parametric approach. GenerativeComponents (GC) was thus developed under the leadership of Robert Aish, the chief scientist of Bentley Systems, since it was claimed by many that 3D modelling programs are not enough to enhance the design thinking and capabilities in architecture. (Fulya ÖZSEL AKlPEK) Lawson, Bryan (1999) even stated that CAD might conspire against creative thought... by encouraging fake creativity. Since other CAD software are limiting architects creative thinking by the use of ready-made geometries in their libraries, GC does not provide any library of geometries, but a point. Each element can be created and is associated with the previous element with each depending on parameters defined by the user. This creates a set of elements linked together by specific relations. Changing a parameter will affect the whole system and this gives designers more control both over design and computation. In fact, GC is shifting the mentality and habits in design. It is opening up the potential advancement in computational thinking in architecture where its practitioners are concerned with the understanding of the geometry and its relationships or associative geometry where they will then have higher levels of control over the systems. The SmartGeometry Group (SGG) even stated that architecture is fundamentally about relationships. (Fulya ÖZSEL AKlPEK)

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On the other hand, Branko Kolarevic (2008) claimed that the capacity parametric computational techniques to generate new design opportunities is highly dependent on the designer’s perceptual and cognitive abilities while others are questioning whether the designer is a coder but GC does not require its users to have knowledge of coding and scripting. Despite not requiring any basic knowledge, the cognitive load is increased at the beginning of the conceptual phase. It can even become extremely difficult to manage the complexity of the designed schema when too many different relationships are involved. Woodburry (2010) argued that conventional design tool is easier and quicker in creating models and even in erasing parts of the systems as they are all independent of other objects. It is however more complex to modify as compared to parametric modelling where the system acts as a whole. Yet, the creation phase is time consuming. Woodburry even stated that parameterisation increases complexity of both the designer task and interface as designers must model not only the artefact being designed but a conceptual structure that guides variation. Ipek Gursel Dino further added that the flexibility of parametric modelling is limited to the parameters that define the schema and that a drastic problem reformulation that requires algorithm alteration might cause the parametric model to collapse at once.

Parametric modelling has a different approach from other generative systems by allowing a stepwise control over the design process which creates multiple solutions for explorations. Parametric modelling is not only useful in the design process but also during the manufacturing process. In these cases, objects are mass customised thanks to parametric modelling which support multiplicity and variation by allowing the production of many objects with a slight measurement differences while still belonging to the same family. A completed modul can thus be changed, modified and regenerated while conforming to pre-set conditions. The parameters can be changed without changing the relationship. (Fulya OZSEL AKIPEK)

Ipek Gursel Dino stated that parametric manipulation of form is particularly valuable in performance-driven design processes while Branko describes it as essential. Through performative architecture, parametric modelling is a leading generative system as it acts as a role model. It integrates the performance analysis and evaluation with the design synthesis in a single process, making the building more efficient and thus sustainable.

İpek GÜRSEL DİNO, Creative design exploration by parametric generative systems in architecture (2012)http://www.academia.edu/1821083/CREATIVE_DESIGN_EXPLORATION_BY_PARAMETRIC_GENERATIVE_SYSTEMS_IN_ARCHITECTURE

http://www.referenceforbusiness.com/small/Co-Di/Computer-Aided-Design-CAD-and-Computer-Aided-Manufacturing-CAM.html#ixzz2OE4m0R1tw

Fulya O.Akipik, Sebnem Y. Cinici, Tugrul Yazar, Computational design, Parametric modelling and Architectural education (2008)http://www.academia.edu/761446/COMPUTATIONAL_DESIGN_PARAMETRIC_MODELLING_AND_ARCHITECTUR-AL_EDUCATION_Sebnem_Y._Cinici_Fulya_O._Akipek_Tugrul_Yazar

Notes:Rodrigo GARCIA ALVARADO, Jaime JOFRE MUÑOZ (2012). The control of shape: Origins of parametric design in architecture in Xenakis, Gehry and Grimshaw

The Waterloo International Station in London has a particular roof designed from a parametric approach. The design was modelled in the software I_EMS by Lars Hesselgren and afterwards re-modelled by Robert Aish with GenerativeComponents (GC). The roof structure consists of pairs of three pinned bow strings arches with the centre pin displaced towards one side to create the undulation in height from west to east. The structure is a long sinuous plan that narrows from 50m wide to 35m at the platform end. While being formed by two dissimilar curved trusses, the beams make up to 35 modules each varying in dimensions.

The trusses were defined by a program that modifies the inner measurements of each module according to the proportional scale factor to the length by means of Pythagorean relation keeping the centres for the radial layout of the smaller pieces. By propagation of the formula, changing the wide of the structure (the chords of curves) and maintaining the central axis like a curved profile. Such produces a continuous surface with a variable section, with proportional heights of the beams according the lights of support. The mathematical description enabled the generation of each design by means of altering the numerical parameters (R. Alvarado, 2012)

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Fig 11. The Waterloo International Station designed by Grimshaw Architects.

Fig 12. The Parametric development of the roof trusses.

Notes:Rodrigo GARCIA ALVARADO, Jaime JOFRE MUÑOZ (2012). The control of shape: Origins of parametric design in architecture in Xenakis, Gehry and Grimshaw

Fig 11. The Waterloo International Station designed by Grimshaw Architects.

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Fig 12. The Parametric development of the roof trusses.

Alongside the beach, the key feature of this park is its 50 year old black pine forest and the design challenges are to minimize the construction impact to the natural environment. The curved form was strategically designed to allow the 45 meters long bridge fit into the natural environment while at the same time provide a connection between the city and the beach park.

Special steel structure was designed to fit the complex from at the same time create big span. Parametric design technique has been adopted throughout all design process i.e. form finding, structure optimization, facade penalization and construction documentation, which make sure the complex shape can be “made” by local low technology manufacturer. “Low Technology Parametric Design” is our strategy to face China’s current construction situation.

In both situations, architects are acting more like mathematicians with all their parametric equations. However this has enabled them to create a smooth and continuous curved structure with many variations as each part of the curve is connected to each other by a relationshp. Moreover digital technologies has facilitated the manufacturing of such complex structures.

Fig 13. The Pedestrian Bridge in Rizhao, China by HHD_FUN Architects

Fig 14. A side view of the pedestrian bridge.

Fig 15. The variations in the bars are all related by a parametric relationship.

Notes:http://www.archdaily.com/293031/pedestrian-bridge-hhd_fun-architects/

Fig 16. Beijing National Stadium, known as the Bird’s Nest designed by Herzog & de Meuron Architekten,

Fig 17. The Beijing National Aquatics Centre, the Water Cube designed by PTW Architects

The Bird’s Nest and the Water Cube in Beijing, China are two buildings whose design, engineering and construction relied entirely on generative design, also known as parametric design. Such approach has enable multiple versions of the design to reach an optimum one. J Parrish, director of ArupSport, the division of Arup at the leading edge of large-venue design, and also a cofounder of SmartGeometry acknowledged the use of parametric being crucial in redeveloping the design. It also opens up new potential for innovations and in a very short time.

“Using parametrics, I was able to investigate far more alternatives. We built version 34 because it was better. But version 1 would have worked fine. Generative design allowed us to get better results in a fraction of the time." “I could do in a morning what used to take me a month," Parrish added.

The advancement in digital technologies enables more possibilities to be explored. “but to resolve a particular iteration using conventional CAD techniques would take so much time that, at best, just one or two versions would have been considered.”

Combined with other new technologies such as real-time rendering and 3D printing, parametrically enabled rapid prototyping amounts to a new way of performing architectural design — arriving at optimum solutions using side-by-side comparisons of multiple, slightly different versions, rather than depending on the "flashlight in the dark" of one designer's genius (Angus W. Stocking, 2009).

Angus W. Stocking stated:“GenerativeComponents, a relatively new technology that facilitates quick exploration of what-if design alternatives that can result in free-form buildings incorporating innovative materials and assemblies.”

The main questions again is how the development of GC technology is changing the approach to building design for many architects.”

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Fig 19. The ceiling over this pool showcases the Water Cube’s “soap bubble-like” structure, which was designed with parametric software specially written for the purpose.

Fig 18. The optimal design for the Water Cube was determined by analyzing multiple configurations of the thousands of steel members and connecting nodes.

Fig 17. The Beijing National Aquatics Centre, the Water Cube designed by PTW Architects

A complementary approach also is possible. Rather than using multiple versions to decide what is best based on comparison, architects can instead use computing power to find structural solutions that are self-organizing; that is, not decided on by an individual but arrived at by genetic algorithms that iteratively apply relatively simple rules. The Water Cube's soap bubble-like structure is an example of this approach.

Arup used MicroStation, MicroStation TriForma, Bentley Structural, and Bentley's generative design technology for its unique design based on a natural pattern of organic cells and the formation of soap bubbles.To manipulate this complex geometric system dynamically, Arup wrote parametric software that automated the drawing and analysis process. Based on specified design constraints and less than 190 loading scenarios, the algorithm iteratively checked the distribution of forces through the entire structure based on specific member sizes, allowing the team to test different design configurations and receive feedback within 25 minutes. The result was a spectacular building with a sophisticated structure that is optimized in terms of material weight-to-strength ratio, and it was achieved with relative ease. In addition to the structural advantages, Arup estimated that it saved $10 million on design costs alone compared with traditional design methods.Yet Stocking stated that “Generative design proponents agree that it isn't that architects are now using computers to do things that couldn't be done previously. Rather, computers are enabling architects to take on design tasks that would otherwise be inconceivably tedious. Does it mean that computers are now controlling and designing the process? I guess that computers can act as enabling tools to generate more alternatives with the new technology emerging together with new design approach.

Angus W. Stocking (15 Act 2009), Generative Design Is Changing the Face of Architecturehttp://www.cadalyst.com/cad/building-design/generative-design-is-changing-face-architecture-12948

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