Parametric modification

Parametric Modification

Parametric Modification Shuaibin Wang

Macro Micro Studio

Contents Contents Introduction

5

1. About Parametric Design

7

1.1 The origin of parametric design

9

1.2 Traditional CAD VS parametric model

11

1.3 Summary of current parametric practice

15

2. Two Precedents Analysis

23

2.1 wetGRID by NOX

31

2.2 Taichung Metropolitan Opera House

by Toyo Ito

33 41

3. Practice On Studio Project 3.1 Brief introduction

51

3.2 Geometry constrains

51

3.3 Geometry optimization

53

4. Conclusion

61

4.1 Current parametric design problems

63

4.2 Summary of parametric design process

65

Bibliography

71

NOTES: 1. <Machining Architecture NOX>

by Lars Spuybroek, NOX office, Netherlands, 2005

Introduction

â&#x20AC;&#x153;We used complex digital choreographies to start the procedure but not to end it...â&#x20AC;? 1

Born as a highly computer-based morphology technology, parametric design is being practiced on different software platforms in different stages of both architecture design and construction.

Parametricism promised to be a style that invents novel ways of shaping matter to produce unexpected spaces. But recently every form emerging out to be inexplicably same. How is Parametricism going to keep its promise?

This is a proposal trying to explore the reason behind this phenomenon, and trying to explore the relationship between parametric design methodology and modernist way of thinking. To state the problems of current parametric design practices, it takes a research into the origin of parametric design, combined with two precedents analysis that represent two typical parametric design methodologies which reflect the current Parametricism practice context. It also relates to the Energy autonomous studio project, to further explore the possibility of applying parametric design into part of the modernist design process.

NOTES: 1. <Integrating Advanced Computer-Aided Design, Manufacturing, and Numerical Control: Principles and Implementations>

by Xun Xu, University of Auckland, New Zealand, 2009

1. About Parametric Design A summary of parametric design development

The architecture design becomes highly computer aided, people start to realize the software used in architecture design is more than a substitute of ruler and compasses. â&#x20AC;&#x153;The parametric design can be described as a method of linking dimensions and variables to geometry in such a way that when the values change, the part changes as well.â&#x20AC;? 1 In a parametric system, a parameter is variable to which other variables are related, and these other variables can be obtained by means of parametric equations.

Parametric design changes the traditional way of direct spatial design to the computer aid modification design. Design modifications and creation of a family of parts scan be performed in remarkably quick time compared with the redrawing required by traditional Computer Aided Drafting. And the parametric modification can be accomplished by script or manually.

picture 1

picture 2

the Barcelona Fish

a plane model in CATIA

NOTES: 1. Emergent Design Group website (http://web.mit.edu/edgsrc/www/) picture 1. http://www.flickr.com/photos/darrellg/4257629248/ picture 2. http://www.evektor.cz/en/aircraft-design.aspx

1.1 THE ORIGIN OF PARAMETRIC DESIGN

The concept of parametric started from the mechanical industry and animation industry.

The first parametric practice in architecture could be the Frank Gehry`s work of the Barcelona Fish for the 1992 summer Olympic game. (see picture 1) The project’s financial and scheduling constraints prompted James M. Glymph, a partner in the firm, to search for a computer program that would facilitate the design and construction process, leading to the adoption of CATIA (computer aided threedimensional interactive application).

The sculpture was modeled entirely in 3D and delivered directly to the fabricators as a 3D model. By the time, the CATIA is only used in mechanical industry for plane design and production. (see picture 2) In late 1990s, animation-based software like Maya and 3Dmax, begin to be used in architecture design. One of the pioneers in 1997, named the Emergent Design Group (EDG) in MIT. “The group develops simulations, tools, prototype designs and building systems with a focus on the emergent properties of materials. Projects break new ground by combining developments in modeling theory, intelligent systems, organizational theory and the science of dynamics to enlarge the space of possibility for contemporary design and computation.”1 They use script write tools specific to the field of their research. The most successful ones are GENR8(2001), Weaver(2001), Agency(2000), MoSS(1999). These would be the first parametric design programs for architecture.

picture 1

picture 3

MOSS (1999)

GENR8(2001)

NOTES: 1. Emergent Design Group website (http://web.mit.edu/edgsrc/www/) picture 1. picture 2. picture 3. picture 4.

http://web.mit.edu/edgsrc/www/moss/index.html http://web.mit.edu/edgsrc/www/agency/index.html http://web.mit.edu/edgsrc/www/genr8/index.html http://web.mit.edu/edgsrc/www/weaver/index.html

picture 2

picture 4

Agency(2000)

Weaver(2001)

1.1 THE ORIGIN OF PARAMETRIC DESIGN

“MoSS(1999) is a research program that utilizes Lindenmayer systems to generatively model or grow surface structures within a three-dimensional shaping environment.

The environment adds controlled flexibility to the system which can emulate real world constraints including material properties, applied, and dynamic loads. MoSS allows the user to specify a base grammar and guide growth through the application of boundary and field conditions. The software outputs files to CAD/CAM applications allowing for three-dimensional testing in physical models. The investigative software is written in C++ as a plug-in to Maya.

Agency(2000) involves a methodological component, researching evolutionary programming techniques, and a design component, applying emergent technologies to the development of distributed systems. The software is noteworthy for its agentbased evaluation of fitness and allowance for direct user interruption and reintegration of phenotypically modified individuals. The investigative software is written in C++ as a plug-in to Maya.

GENR8(2001) is an innovative design tool that fuses an expressively powerful universe of growth languages with evolutionary search. The software combines 3D map L-systems that are extended to an abstract physical environment with Grammatical Evolution.

Evolutionary Algorithms (EA) typically adapt ‘on-line’ but GENR8 is designed to accommodate the back and forth control exchange between user and tool during on-line evolutionary adaptation. Users may interrupt, intervene and then resume GENR8.

This allows for interactive design evaluation and computational multi-criteria search. The investigative software is written in C++ as a plug-in to Maya.

Weaver(2001) Explorations of industrial braiding and weaving led to the design of a grammar capable of describing and generating woven strands. Weaver applies the pattern to a user-defined surface. The resulting weaves can be complex and depend both on the description of the weave pattern and the topology of the surface on which the weave is applied. Weaver is written in MEL and runs in Maya.”1

picture 1

picture 2

Sketch Up model

Maya Polygon Model

NOTES: 1. Emergent Design Group website (http://web.mit.edu/edgsrc/www/)

1.2 PARAMETRIC MODELING VS CAD MODELING

In architecture, 3D Models software is elaborated by some commercial version of one of the following three techniques: polygonal meshes, solid models or parametric surfaces such as NURBS. Although the techniques may different, there is always a script, which defines the commands shown on the interface of the modeling software. The parametric modeling software opens the script to user, and allows user to edit or write the custom command, or simply linked the existing commands to create a series of commands working process.

The 3D objects created by these linked system, often has a few key parameters. While parameters are changing, the object changes as well.

1.2.1 TRADITIONAL 3D CAD SOFTWARE The first method - polygonal mesh, is mostly used for architects today. The typical example is Google Sketch Up.(see picture 1) Which provide an easy and fast way to build 3D object by start from 2D faces, and the use of “pull surface” to extrude the surface to a particular height.

This is due to the characteristics of architectural models that are mainly composed of planar surfaces. The limitation is obvious, the definition of a curve in polygonal mesh is automatically transformed in to polyline, which makes the accuracy is very limited. The “pull surface” command could only extrude planer surface in perpendicular direction. It is usually hard to control the third dimension operations.

The advantage of the polygonal mesh modeling is that it is always easy and free to edit and change the object after creating the basic object. Actually many users are start from a basic simple object, and then keep edit and “carve” the object to finish the model. (see picture 2)

picture 1

Inventor Solid Model

picture 2

Rhinoceros NURBS surface

picture 3

Maya NURBS model transform to Polygon model

1.2 PARAMETRIC MODELING VS CAD MODELING

The second method - Solid models, are also widely used due to the fact that that they allow Boolean operations to create more complex forms. Which is now also used in most of the polygonal mesh software. The user could define the object to be solid or only covered by surface. The typical example could be 3D autodesk CAD, autodesk Inventor or Solidworks. These software are often used in mechanical industry.(see picture1) NURBS or the like are not as popular as polygonal meshes. But lately it is becomes known by more and more designers.

A typical NURBS surface is defined by a U-V system. The U direction defined as a profile section curve, while the V direction defined as a rail curve, and a NURBS surface is the result of a profile curve sweeping along the rail curve. (see picture 2) Since a line is simply defined by two points, but a curve is constantly changing direction, it needs much more control and definition to describe. The control system for curve in NURBS is made up of several control points and an equation which generates the curve, based on the control points. Which matches the definition of parametric design. Which means a NURBS curve is a mini parametric system, control points are the parameters, and the equation behind it is the modification. With the change of control points, the curve changes. Since the surface based on U-V system was defined by curves. Which means once the control points changes, the whole surfaces changes as well. The typical software based on NURBS would be Rhinoceros.

Software like Maya or 3Dmax could build both polygonal meshes model and NURBS surface model. And even could transfer an existing model into both ways. What`s worth mention is that, it is often easier to transfer a NURBS model into meshes model. Complex meshes model may not able to transfer into NURBS.(see picture 3)

picture 1

picture 2

Sketch Up with Ruby script

Rhinoceros with Grasshopper

NOTES:

picture 3

Photoshop control slider

picture 1. http://news.sketchucation.com/beginningruby-2-writing-a-script/

1.2 PARAMETRIC MODELING VS CAD MODELING

1.2.2 PARAMETRIC 3D MODELING Since parametric is a way of using 3D modeling software rather than something totally new about 3D computer modeling. Many traditional 3D modeling software could become platform for parametric modeling. For example, if you know the Ruby Programming Language, you can easily use Google Sketch Up as a parametric modeling platform. (see picture 1) Parametric is such a generic concept and widely used, which makes it hard to classify by the actual techniques of the software. But the main concept is always the same, thus linking parameters and build modifications. Based on the form of interface of the software, they can be classified as the following: a. Graph based When we talk about parametric software, we tend to think of graph based tools. The two major ones being Generative Components and Grasshopper. Both of these use a two dimensional relationship graph to express associations between geometry.

Generative Components is the older of the two and as such is more frequently cited to in books and papers and projects. Grasshopper has the benefit of a more modern interface, making coding as fun as playing with Lego. (see picture 2) b. Stack Based Stack based tools store transformations to objects in a one dimensional stack. Changes can be made at any location in the stack and propagated through the remaining stack.

The best known of these is 3dsMax. 3dsMax also has the ability to link values together through the Wire Parameter option, and these can even be wired to sliders. The Smart Filters in Photoshop also work as a parametric stack. (see picture 3)

picture 1

picture 2

CATIA associative history model

Building Information Model

NOTES:

picture 3

Processing script based design

picture 1. http://solarisdesign.blogspot. co.uk/2011/05/catia-for-acrhitecture-bysolaris.html picture 2. http://buildipedia.com/on-site/buildingnews-trends/contractors-look-to-bim-tostreamline-construction picture 3. http://wiki.processing.org/w/File:Kokkugia_ kiev.png

1.2 PARAMETRIC MODELING VS CAD MODELING

c. Associative history Associative history is an editable record of how an object was created. Maya uses associative history enabling you to do things like create a loft from two curves and then go back and edit one of those curves, updating the loft. The major software in this space is CATIA/Digital Project, used on The Birds Nest, Sagrada Família and all of Frank Gehry’s buildings. (see picture 1) d. BIM Both Revit and Archicad have parametric tools. Revit allows the creation of Revit Families, which are driven from parameters. Walls can also be constrained in a manner similar to CATIA. And the new conceptual massing tool features associative history. Archicad works through the Geometric Description Language, which allows you to code parametric objects (sort of like Revit Families).

Although software like Revit, Archicad and CATIA or Digital Project claim to be the expert in BIM software. The concept BIM is not limited by the software themselves. BIM (Building Information Modelling) ultimate goal is to assemble in a single data base fully integrated and interoperable information that can be used by all members of the design and construction team and ultimately by owners/operators throughout a facility’s life cycle. The aim is to share information from different project disciplines and building trades in order to facilitate the design, construction, and building management process. (see picture 2) e. Scripting Based The script of a 3D modeling software, which the developers use to write default commands is the most powerful tool for parametric design. For example, like the Rhinoscript for Rhinoceros, the MEL for Maya, 3Dmaxscript for 3Dmax and Ruby for Sketch Up. The use of script in 3D modeling, confuse the boundary between parametric software and traditional CAD software. Parametric becomes a way of using software rather than a specific kind of software.(see picture 3) There is also a kind of software like Processing, which is totally based on script.

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CNC model

different unit fabricate

NOTES:

picture 3

digitally controlled bricked wall

picture 1. http://coorlas.blogspot.co.uk/2011/08/ academic-blob.html picture 2. http://mlab.cca.edu/2008/12/1-dayworkshop-modeling-for-digital-fabrication/ picture 3. http://www.designbymany.com/content/ wavy-brick-wall

1.3 SUMMARY OF CURRENT PARAMETRIC PRACTICE

Having been through nearly a decade development in architecture, people now have a variety of architectural parametric software, architects are using different attitude towards the software and produce works with parametric technologies in different ways.Which makes it hard to classify by the software or the techniques.

Generally, based on different stages the parametric technology is applied, they can be classified as following: 1.3.1 Digital Fabrication Digital fabrication is a very limited way of using parametric design. The actual parametric part is only about use parametric software to generate and control the fabrication. The design part could be very traditional, after the drafting and sketch design, parametric technique is used to manage and control the form or geometry. Combined with the development of digital fabrication manufacture technology, and pushing boundaries to bring complex geometry into physical construction.

The most widely used parametric method in this area is “intersect”.

Usually the geometry is designed first, then use parametric software to cut a series of section in both directions, then use CNC machine to cut the material and assemble the pieces by hand. (see picture 1) Another popular method is “flow along surface”.

The logic is based on the definition of NURBS surface. Since the surface is generated by U-V system, every point on the surface would have a U-V coordinate.

Based on the coordinate, a grid flows along the surface would be generated. With the help of gird, different types of units could be applied to the surface. The layouts could either be different units layout and fabricated,(see picture 2) or using same units but combined in a certain way digitally controlled. (see picture 3)This is also the same way NURBS surface transformed into polygonal meshes.

picture 1

BIM model by WRNS studio (http://www.wrnsstudio.com/)

1.3 SUMMARY OF CURRENT PARAMETRIC PRACTICE

1.3.2 Parametric Associated Design The key concept of parametric design is to build the modification. By linking the relevant information, every time the parameters are changed, the system would update the linked parts, and give the new results. This allows the designer to test a lot of possibilities in short time, and allows people from different apartments work coherently together. For these architects, parametric is a way they work togather.

The Building Information Model (BIM) is created under this concept. For this type of practice, their attitude for parametric design is that, the parametric models, systems, and ideas are used only to rationalize architectural designs and test more possibilities, save time and budget before the building is constructed, but the design could be totally traditional. (see picture 1) The parametric associated design create opportunity for architects to work together more efficient than ever. UNstudio is one of the most famous examples of this field. UNstudio stands for United Network Studio, with highly coherent parametric system control and organize work from sketch design to detail design and construction, their works achieved high finish quality with complex form.

picture 1

Beijing National Aquatics Center

NOTES: 1. Parametric practices: Models for design exploration in architecture

by Gerber, David Jason, D.Des., HARVARD UNIVERSITY, 2007

1.3 SUMMARY OF CURRENT PARAMETRIC PRACTICE

1.3.3 Parametric Emerging Design While some architects think parametric models, systems, and ideas are used only to rationalize architectural design, other architects think the parametric system should be used to generate form or search for spatial solution, and that is parametric emerging design. â&#x20AC;&#x153;This is a notable departure from the dominant assumption that parametric design is solely applicable in post-rationalization processes or for design development and delivery. â&#x20AC;&#x153;1 Architects practicing in parametric emerging design often choose a proper generate system, base on the site analysis data, generate the most efficient form, and take into further detail design. Usually the complexity of the form is impossible for designers to imagine and drawn by traditional CAD software.

The key difference between parametric emerging and parametric association design is the use of the generation system. Several parametric morphology generate system (such as Cellular Automation, Voronoi, L-system, minimal surface system, Panelization) are classical and popular been widely applied in many architectural practices. Typical precedent is the China National Aquatics Center, using Voronoi system generate its structure system. (see picture 1) But still they are highly controlled within traditional way of thinking in design process, the applied parametric system is usually structured as an element responding for a specific issue. Practicing architects today are trying to cooperate the two different ways of thinking, and keep redefining the concept of parametric design.

The typical precedent is the Taichung Metropolitan Operal House designed by Toyo Ito. Which will be further disscussed in next section.

picture 1

Fish Swarm

picture 2

Processing script urban analysis

NOTES:

picture 3

Minimal surface system

picture 1. http://www.nytimes.com/2007/11/13/ science/13traff.html?_r=1 picture 2. http://dimitrie.wordpress.com/category/ boids/ picture 3. http://www.bathsheba.com/math/gyroid/

1.3 SUMMARY OF CURRENT PARAMETRIC PRACTICE

1.3.4 Emerging Algorithm Research For people who are working on research of emerging algorithms, they are the drivers of the field of parametric design. But there are hardly actual architecture practice works been built.

Researching in parametric morphology generative system also called Form-Finding.

Mathematically looking for solution of describing complex geometry or natural phenomenon simulation. And transfer the mathematical relationship into computer language, applied to different software platform as a generative system to be applied into real project.

For researchers working on emerging systems, their research areas are unlimited, anything could be the inspiration of the start of a new system. A famous study into the behavior of birds flow, which is called “swam intelligence”,(see picture 1) now is widely used to simulate the crowds flow and to predict the most active area in large urban public program. (see picture 2) The Voronoi system is often used to looking for minimize material structure strategy.

There is also emerging systems which is made for specific material, to explore the boundary of material property. The minimal surface system is first written to simulate the form of soap bulb, which is now widely used in tensioned membrane structure, and also one of the most popular free surface generation system.(see picture 3)

All above four types of attempting are being called “parametric design”, but the difference is obvious in the way architects are using in their practices.

NOTES: 1. <Integrating Advanced Computer-Aided Design, Manufacturing, and Numerical Control: Principles and Implementations>

by Xun Xu, University of Auckland, New Zealand, 2009

2. Two Precedents Analysis

Two projects were introduced into this section, one is the “wetGRID” by Lars Spuybroek and his studio, NOX. Which is designed and build in 2000, when the concept of parametric design and “Parametricism” is not actually emerged and known by few people.

Another one is the “Taichung Metropolitan Opera House” designed by Toyo Ito, the ground-breaking ceremony for the second-stage main construction was held on December the 3rd, 2009, and the theater will take over four years to complete.

The project used the minimal surface system to generate the basic form, and have a very advanced parametric system to control the construction.

picture 1

Overview of the porject

NOTES: 1. <Machining Architecture NOX>

by Lars Spuybroek, NOX office, Netherlands, 2005 picture 1.

<Machining Architecture NOX> by Lars Spuybroek, NOX office, Netherlands, 2005

2.1 wetGRID

2.1.1 Project Introduction

The project is an exhibition design for “vision machine” in France. Which involved using physical model to start generate the basic guide curves. Combined with parameter-linked computer modeling, base on the guide curves generate and explore the form to use as a exhibition space. And the project also trying to use digital fabrication to construct. Back in 1999, all these technologies used in the project were very innovative and forward looking.

“The exhibition explores the area between the emerging view and the projected view, between subjective and objective vision.

The design methodology consisted of steps, machining stages, in which each piece of new information is passed on to a new level. ” 1

picture 2

Paper concept model

NOTES: 1. <Machining Architecture NOX> by Lars Spuybroek, NOX office, Netherlands, 2005 picture 1. picture 2.

<Machining Architecture NOX> by Lars Spuybroek, NOX office, Netherlands, 2005 <Machining Architecture NOX> by Lars Spuybroek, NOX office, Netherlands, 2005

picture 1

Concept diagram

2.1 wetGRID

2.1.2 Project Development Process The process starts from the route analysis of the site, base on the subjective experience, they defined four main routes in respond to the geometry grid of the existing building.

“In the first stage, the four rotting force interact with a linear structure derived from museum. These four vortices connect conceptually to four types of vertigo and hallucination.”1 “In the second stage the rotating lines transform into a paper model, which is digitized into a set of complex, blister-like volumes that emerge from an undulating surface. The volumes were sliced into the computer to generate a set of lines that form a diagrid of curved ribs to be cut out of plywood using precise CNC laser-cutting techniques.” 2 “We used complex digital choreographies to start the procedure but not to end it, and opted for a combination of digital and analogue techniques.”3 The regularly spaced lines reflecting the structure of the existing museum(a) are moved away from their formal symmetry(b), then returned to equilibrium through an analogue technique with paper (c).(see picture 1) The final Formfinding was determined through a simple added algorithm: if the lines in the digital animation move closer by more than 50% of their original distance, the analogue paper line is split in two and connected to its neighbor by a paper clip.

This function ensures that the procedure stops by itself instead of having to be freezeframed. (see picture 2) Ultimately, this is a Gothic principle: producing surface by bifurcating lines.

picture 1

CNC cutting pattern

NOTES: 1. <Machining Architecture NOX> by Lars Spuybroek, NOX office, Netherlands, 2005 picture 1. <Machining Architecture NOX> by Lars Spuybroek, NOX office, Netherlands, 2005

2.1 wetGRID

2.1.3 Construction Control The innovative methodology used in creating the free form of the exhibition space end up with complex geometry which is impossible to build by traditional construction.

The use of CNC in digital fabrication is quite a common technique to bring computer model into construction, this project is probably the first time use CNC in architecture construction.

The capability of CNC used in the project is quite limited, but base on the limit of the machine, the structural components were split into small parts that could fit into the panels. (see picture 1)

â&#x20AC;&#x153;In the past this kind of curvature would have been inconceivable in architecture because each curve would have had to be reduced into circle segments, drawn onto large sheets of paper (including the radius and the angle of each arc), then cut by hand from plywood sheets.

Today e don`t even need to know the formular of cubic curves because the mathematical information of the complex geometry can be passed directly from the computer to the CNC machine, which cuts each of the lines out of the plywood by laser.â&#x20AC;? 1

picture 1

wetGRID under construction

NOTES: 1. <Machining Architecture NOX> by Lars Spuybroek, NOX office, Netherlands, 2005 picture 1. <Machining Architecture NOX> by Lars Spuybroek, NOX office, Netherlands, 2005

2.1 wetGRID

2.1.4 Conclusion To summarize the process, at first stage, use physical model to start explore the material or site information, then base on the physical model experiments experience, conclude a transform constrain. Which many architects now prefer to start exploring the mathematic experiments in computer, or writing scripts and emerging systems to generate the basic guide lines as start point.

This part of parametric experiment is “emerging algorithm research” today.

Then set up geometric transform constrains, and use scripting write into computer, and generate more complex and accurate form. As today there are specialists working in the geometry generate systems research, many architects choose from the existing system to generate their own schemes. Although many other architects like to combine traditional thinking and analysis as their project start point. Only use computer parametric model to rationalize and modify their schemes. It is between “parametric associative design” and “parametric emerging design”.

The last stage is construction, since the project introduced CNC technology into architecture in 1999. After a decade development, the technology is widely used and more advanced physical modeling technologies like 3D-print is developed and used in architecture design and construction.

Which are all belongs to the field of “digital fabrication”.

From the project, we can clearly analysis how people are attempting to use computer at early stage of design, and how the development of technology gives the opportunity to make it happen. The process mixed and explored lots of concepts and ideas, which are widely practiced and used today.

picture 1

Model of the project

NOTES: 1. Interview by website Design Boom ( http://www.designboom.com/weblog/cat/9/view/9561/toyo-ito-taichung-metropolitan-opera.html ) picture 1. http://www.designboom.com/weblog/cat/9/view/9561/toyo-ito-taichung-metropolitan-opera.html

2.2 Taichung Metropolitan Opera House

2.2.1 Project introduction

“While other major cities in taiwan are all known for something, taichung, a city of roughly 1 million residents whose name means ‘central taiwan’ in chinese, has trouble finding anything to distinguish itself from taiwan’s other metropolises. Today it is seen as one ofthe most cultural cities in taiwan.” 1

As the architect Toyo Ito says, “Architecture has to follow the diversity of society, and has to reflect that a simple square or cube can’t contain that diversity.” (see picture 1) But the social context has more influence to the project. Ever since 2006, the parametric design is becoming more and more popular, architects working in the field claim themselves “Parametricism” and they saw future in the parametric technology, their ambition is another architecture revolution driven by the thoughts that the computer is so powerful that it will take place of traditional way of thinking in architecture design.

picture 1

Minimal surface as basis of the form

NOTES: 1. From Wikipedia (http://en.wikipedia.org/wiki/Minimal_surface) picture 1. http://www.designboom.com/weblog/cat/9/view/9561/toyo-ito-taichung-metropolitan-opera.html

2.2 Taichung Metropolitan Opera House

2.2.2 Minimal surface system According to the definition in the first section, the project is a typical Parametric Emerging design.

This type of parametric practice often chooses a parametric morphology generate system as the basis. The system used in this project is the “Minimal Surface” system.

“In mathematics, a minimal surface is a surface with a mean curvature of zero. These include, but are not limited to, surfaces of minimum area subject to various constraints.

Physical models of area-minimizing minimal surfaces can be made by dipping a wire frame into a soap solution, forming a soap film, which is a minimal surface whose boundary is the wire frame.” 1 Base on the definition, scripts were written to generate all kinds of surface, with properties like optimize the material use or structural efficiency. When dealing with relevant issues, the system can be directly used to generate proper surface under the given framework.

The project has a obvious identity of using minimal surface system.

The spaces are generated according to the requirements of different volumes, and the form also gives complexity in the connection between different areas.

All these properties gives architects possibilities to explore and further develop the scheme.

picture 1

Sketch drawing by Toyo Ito

NOTES:

picture 2

a modernism way of exploring the space

picture 1. http://www.designboom.com/weblog/cat/9/view/9561/toyoito-taichung-metropolitan-opera.html picture 2. http://www.designboom.com/weblog/cat/9/view/9561/toyoito-taichung-metropolitan-opera.html

2.2 Taichung Metropolitan Opera House

2.2.3 Occupying the space The sketch drawing shows a combination of design thinking of parametric design and traditional modernism design.

The surface and structural form is generated by the minimal surface system according to a generic function need. But when further developing the scheme, architects are using very traditional sketch to explore the space and occupying different activities into the space, and give each space further definition. (see picture 1) What â&#x20AC;&#x153;parametricismâ&#x20AC;? claims is that, the parametric design is analysis data based design, which keeps the designer`s subjective out of the designing process, which would end up with a objective rational design.

But when actually dealing with a complex scheme, after all the technique parts of formfinding process, architects still need to used their life experience and subjective mind to occupy the functions into the space.(see picture 2) While other architects who are using minimal surface system, they are more focus on the generate system itself to generate more complex and specific minimal surface in respond to the function of the building, base on the form results and feed back loop, keeping develop the modification of the system rather than accepting the form from generate system and explore the possibility in a modernism way.(see picture 3)

picture 1

construction diagram

NOTES: 1. Interview by website Design Boom ( http://www.designboom.com/weblog/cat/9/view/9561/toyo-ito-taichung-metropolitan-opera.html ) picture 1. http://www.designboom.com/weblog/cat/9/view/9561/toyo-ito-taichung-metropolitan-opera.html

2.2 Taichung Metropolitan Opera House

2.2.4 Construction “The structural system is developed together with the construction method to realize the freeform geometry in rational and efficient manner. The freeform concrete surfaces are shotcrete (spray concrete). It is commonly utilized for tunnel construction and suitable for curved surface. It can be shot horizontally or vertically. rather than constructing doubly curved formwork that is expensive and time consuming on site, the temporary structure in the void creates faceted surfaces that best-fit the finished surface. Between the temporary steel work, expanded metal mesh is expanded metal mesh spans between the temporary steel work to act as faceted formwork. 150 mm thick concrete can be shot at one time. The surface layer of 25 mm is shot separately without large aggregate to achieve smooth surface finish. Concrete thickness varies between 200 mm at the top floor and 350 mm at the bottom.”1 “Typically, an expanded metal mesh is used as a permanent back shutter to which the reinforcing mesh is affixed. The concrete is sprayed onto the expanded metal and the reinforcement is fully enclosed. the concrete is typically sprayed using one of two methods. With the dry process, the dry constituents of the concrete are mixed in a portable batching plant and the water is added to the mix at the nozzle. with the wet process, the water is added to the batching plant and premixed with the dry constituents and the wet concrete is sprayed from the nozzle. the benefits of the wet process are that there is greater control over the concrete mix as the concrete is often mixed off site by ready-mix contractors and delivered in lorries.”2 “It is common practice to apply the concrete in two layers. the first thick layer is usually applied using the wet process. once sufficiently cured, a second, thin finishing layer is then applied using the dry process. It is essential that the finished product is cured appropriately to mitigate shrinkage and to ensure that design strength is achieved.

Spraying concrete is a messy process. some concrete will rebound and some will pass through the expanded metal back shutter. It may be necessary to install temporary protection to avoid polluting the surrounding area.”3

picture 1

a modernism way of exploring the space

picture 2

specific modification to the generate system

NOTES: picture 1. http://www.designboom.com/weblog/cat/9/view/9561/toyo-ito-taichung-metropolitan-opera.html picture 2. http://www.oliverdibrova.com/blg/?cat=4

2.2 Taichung Metropolitan Opera House

2.2.5 Conclusion According to the classification in the first section, this project is a typical parametric emerging design, choosing minimal surface system as generate system. Base on the general function requirements generate the surface form.

But for Toyo Ito, that is the end of the process that parametric design involved, he took the form as the final model, and from that point, the rest of the design is highly modernism way of thinking.

Depending on hand drawing and subjective design experience to further explore the possibility behind the complex form generated by computer, is a rethinking to the concept that using computer script to â&#x20AC;&#x153;designâ&#x20AC;? base on the site data information to be objective during the process.

Is that even possible to be totally objective, or could design really become objective?

While other architects who are using minimal surface system, they are more focus on the generate system itself to generate more complex and specific minimal surface in respond to the function of the building, base on the form results and feed back loop, keeping develop the modification of the system rather than accepting the form from generate system and explore the possibility in a modernism way.

In order to control and construct such a complex form, parametric has come back to the process, for this project, the generic idea come from the generate system, and combined a modernism way of thinking in occupying the space. But back to digital control to construct on site. It challenge the traditional way of design as well as the parametric design.

picture 1

render from northeast view of the studio

3. PRACTISE ON THE ENERGY AUTONOMOUS STUDIO

3.1 Introduction to the Project The project brief is to design and build an energy autonomous demonstrator building. To achieve that, the building should have several main components: a south facing window for passive solar gain, a due south 40degree pitched roof for photovoltaic panel to generate electricity and a high thermal performance envelop to maintain the heat.

Our team have gone through a series of study on each issue and come out with five schemes in the four months of development. Through out the traditional design and research process, we end up with a square based cranked plan, with a due south rectangular pitched roof.

The development process provide experiences on set up the geometry constrains, but due to the complexity of the geometry, the form is still open ended, and several parameters are together affecting the geometry in an unknown way. The implication of the parameters and the overall geometry is too complex to be explored by physical model or traditional CAD modeling.

That is the start point of the following practice.

The following parametric model is build in Rhinoceros with Grasshopper.

Base on the definition in the first chapter, parametric design could be classified as: digital fabrication, parametric associated design, parametric emerging design and emerging algorithm research.

According to the above definition, the following practice is a parametric associated design, using graphic based parametric software.

picture 1

Define the cube length link to roof area and pitch angle

3. PRACTISE ON THE ENERGY AUTONOMOUS STUDIO

3.2 Geometry Constrains Setup a. Basic square plan The project is based on a square plan cube, with a pitched roof orientated due south. PV panels are integrated within the roof form, in response to the studio electricity demand which defines the required surface area of the south-facing roof. On this assumption, in order to model the relationships within the form of the studio, we must adhere to the following parameters: a – side length of the square – angle of the pitched roof S – surface area of the pitched roof The relationship between these three parameters is as follow:

When the solar panel area and the pitched roof angle is defined, the side length of the square is defined as follow:

picture 1

set up the crank factor “b”

picture 2

set up mezzanine factor “c”

3. PRACTISE ON THE ENERGY AUTONOMOUS STUDIO

b. Floor plan In order to push the service unit back to north and push the entrance to the east to meet the landscape, the square plan is twisted. The northeast point where the entrance is located, is pushed towards east for a distance of “b” and the rest of the sides are defined by the two right angle. ( see picture 1 ) The ground floor plan area can be described as follow:

The mezzanine is attached to the north side, leaving south side of the ground floor a double height volume space. The front edge of the mezzanine is step back from the south façade for a distance of “ c ”. ( see picture 2 ) The mezzanine floor plan area can be described as follow:

According to the brief, the floor area of the building is 50 sqm, which means: S + S` = 50sqm, that is also as described follow :

Since the parameter “a” is defined by the solar panel area and the angle of the pitched roof, the only two parameter in the equation is “b” and “c”, which means, the mezzanine floor location and the twisting factor “b” is defined by each other.

When the modification is build, all parameters are linked to control the model, the overall geometry is defined by the three key parameters as follow: S – solar panel area – south roof angle c – the front edge of the mezzanine

picture 1

parameter “c” defines “b”

picture 2

parameter “ “ defines “b”

3. PRACTISE ON THE ENERGY AUTONOMOUS STUDIO

While change the parameters of the modification of the parametric model, as the solar panel area and the south roof pitch is generally settled, the front edge factor “c” is defining the crank factor “b”, which could also described as the more mezzanine floor is pushed to north, the more entrance is cranked to east. ( see picture 1 ) After the link is settled, the geometry can be controlled by the parameter “s” and “ ” as well.

For example, the larger the angle becomes, the mezzanine is pushed forward, the smaller the angel becomes, the mezzanine is pushed backward. ( see picture 2 ) While the mezzanine is pushed to north, it is occupying the space under the ridge line, which maximized the use of the high volume space created by the pitch roof.

picture 2

parameter “ “ defines “b”

picture 2

parameter “ “ defines “b”

picture 2

parameter “ “ defines “b”

3. PRACTISE ON THE ENERGY AUTONOMOUS STUDIO

c. CONTROL OPENING The west side window is located in respond to the ground floor geometry change and the location of the service wall. While the distance between the back wall and the front edge of the window is set by the stair plus the depth of the service wall, which is 1.5 meters in all. ( see picture 1 ) While the entrance opening size is complying the building regulation and locate to the northeast corner of the plan. The minimal width of the entrance is 1.3 meters, which is set in the model. ( see picture 2 ) The east opening on the mezzanine floor is defined by the front edge of the desk and the northeast wall, and the height is limited to the height of the 3-meter panel. The west opening on the mezzanine floor is defined by the front edge and it is a square window, which define the height of the window at the same time. ( see picture 3 ) When the height of the window is higher than the intersect point of the roof, the height is defined by the intersect point. By this way, the window is defined and linked to the mezzanine parameter â&#x20AC;&#x153;câ&#x20AC;?. ( see picture 3 ) The east opening on the mezzanine floor is defined by the front edge of the desk and the northeast wall, and the height is limited to the height of the 3-meter panel.

The south-facing façade is totally open, to maximize the passive solar gain from the sun, which is naturally set within the existing logic.

Above all, the five main opening of the whole building is all linked to the floor plan and other existing elements, there is no additional parameters defined in controlling the opening section.

picture 1

mezzanine floor area becomes larger, the

crank becomes smaller

picture 3

geometry modification

picture 2

mezzanine floor area becomes smaller, the

crank becomes larger

3. PRACTISE ON THE ENERGY AUTONOMOUS STUDIO

3.3 Geometry Optimization The parameter “b” that defines the crank and the parameter “c” that defines the mezzanine front edge are linked, since the mezzanine layout is much more important in terms of the spatial efficiency. The parametric model is build to use “c” defines “b”.

On the other hand, the above relationship exists only if the south facing roof area parameter “s” and the pitched degree parameter “ ” remain the same value. Which means, when the mezzanine parameter “c” is set as an unchanged value, the crank can be defined by the south facing roof area and the roof pitch.

The scheme geometry constrains is quite direct and clear. And the overall form is abstract and simple, compared to other parametric schemes. It seems unnecessary to use parametric software to explore the geometric implications. But the at this level of complexity, as the above process shows, the implication behind the geometry is already beyond designers` capability to imagine by general experience.

The parametric model and the animation shows directly how the crank on the plan is linked to the location of the mezzanine floor, and how every other elements are linked to the key parameters. The parametric model gives the geometry result directly when changing the relevant parameter, without rebuilding the whole model. Which is much more efficient than the traditional CAD modeling.

Also, the parametric model visualized the mathematics relationship between the different elements, which helps architects understand and control the geometry in an easier way. ( see picture 3 )

NOTES: 1. <Architecture Review>, October, 2011, p39

4. CONCLUSION

4.1 Current Parametric Design Problems During the last ten years, there has been an extraordinary development of computer aided tools, which are intended to present or communicate architectural projects.

But there has not been a comparable progress in the development of tools, which are intended to assist design to generate architectural forms in an easy and interactive way.

As the above section discussed, there are a variety of parametric design software and platforms available for different ways to interact or for different stages to assist design projects, but still it is not easy and interactive enough.

Some matured emerging systems are widely used and applied, but after these years of development, people start to realise that â&#x20AC;&#x153;as every form emerging out of Parametricism is inexplicably smooth and undulating, made up of small, gradually changing units.â&#x20AC;? 1 Base on the precedent analysis of Toyo Ito`s project, The main reason for that phenomenon could be found as that the software and platforms are too complex for most designers to use. Which made parametric design becomes an expert tool for a small group of architects or students to really understand and work with.

But for the majority of architects who are also interested and willing to try, they have to start with the most basic and popular generate systems. They are practicing with out fully understand the tools and are not capable to rewrite or modify a project specific form generate system for their own purpose. As a result, their works end up with the same form.

However, with the powerful capability of controlling and modeling complex geometry that parametric design brought to us, there is no reason to step back. From the above sections discussion, there are several ways we can deal with the current situation. As long as there is a systematic parametric design methodology as a guidance.

4. CONCLUSION

4.2 Summary of Parametric Design Process From the lesson we leant from Toyo Ito and NOX architects, it is possible to combine parametric design and modernist way of thinking into a project.

In this section, base on the two precedents analysis and the practice on the energy autonomous studio project, there is a summary of design process.

From design process of the wetGRID project, we will summarize a general parametric design process. Then base on the Toyo Ito`s methodology, we can summerized a more hybrid way of parametric design.

To summarize the â&#x20AC;&#x153;wetGRIDâ&#x20AC;? project process. It starts with exploring physical model and base on the experiment results, setting up geometry transforming and development constrains.

Then write the process into computer, run the program, then modify the form and end up with the design.

With the feed back of a draft scheme, which brings more specific design issues, combine these issues, further develop the project specific emerging system, until the system is specific and detail enough to meet the project`s requirements.

Before get to explore the parametric design process, looking back to the modernist design methodology. Three key elements to structure a scheme is the brief, site and the precedent.

In the following section, base on the same structure, it explores a general parametric design process.

4. CONCLUSION

4.2.1 A General Parametric Design Process For a general design process, the emerging systems often find its inspiration from the natural phenomenon or mathematics constrains. All these parametric design system collections like an electronic precedents library, when dealing with a specific brief, architects can search for relevant systems and further develop it.

According to the brief, several key issues could be identified and used to further develop a project specific emerging system, and use site analysis information data setting up as control parameters to control and modify the draft scheme.

With the feed back of the draft scheme, keep further developing the specific emerging system. In other words, Parametric design is more about develop the project specific emerging or modification system. The scheme is developed through the development of modification system with parameters to control the performance of the system. It is more about the development of different stages of parametric modification.

Parametric design should always focus on developing a project specific emerging system, the existing emerging systems normally should not applied directly to a specific project.

Since they are ofen generic and abstract, once architects are applying the same emerging system without specific development, it would end up with the same inexplicably and yet predictably form.

Unfortunately, that is the situation we are facing, people are questioning about how will Parametricism going to keep its promise. There is nothing wrong with the methodology of parametric design, it is the abused use of parametric design by architects who are neither really understand the design process, nor have the capability of fully control the software.

Which ends up with lots of design works have an inexplicably same form.

4. CONCLUSION

But in reality, every step in the above process needs an expert knowledge and skill in writing and designing the script. However, it is a totally unknown field to most of architects, that is why some architects are trying to apply parametric design to part of their design process.

4.2.2 Other Possible Hybrid Design Process According to the first section, this project is a typical parametric emerging design, choosing minimal surface system as emerging system, generate the surface form based on the general function requirements.

But for Toyo Ito, that is the end of the parametric design process involved, he accepted the form as a given fact, and from that point, the rest of the design is a highly modernist way of thinking.

Depending on hand drawing and subjective design experience to further explore the possibility behind the complex form generated by computer, is a rethinking to the concept that using computer script to â&#x20AC;&#x153;designâ&#x20AC;? base on the site data information to achieve objective during the process.

Is that even possible to be totally objective, or could design really become objective?

In order to control and construct such a complex form, parametric design has to come back to the process, for this project, the generic idea comes from the parametric emerging system, and combined a modernist way of thinking in occupying the space, but back to digital control to construct on site. the whole hybrid design process challenges the traditional design methodology as well as the contemporary thoughts on parametric design.

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1. Reiser. Jesse.

< Atlas of Novel Tectonics >, Princeton Architectural Press, 2005

2. Michael. Meredith. < From Control to Design >, Actar, 2008 3. Lisa. Iwamoto. <Digital Fabrication Architectural and Material Techniques> Princeton Architectural Press, 2009 4. Farshid. Moussavi <The Function of Form >.

Actar and Harvard Graduate School of Design, 2009 5. Farshid. Moussavi < The Function of Ornament > Actar, 2007 6. Lars. Spuybroek.

< Machining Architecture > Netherlands Architectures, 2004

7. Xun Xu.

<Integrating Advanced Computer-Aided Design, Manufacturing, and Numerical Control: Principles and Implementations> University of Auckland, New Zealand, 2009

8. <Architecture Review > October, 2011 9. Emergent Design Group website ( http://web.mit.edu/edgsrc/www/ ) 10. Gerber, David Jason, D.Des. Harvard University, 2007

<Parametric practices: Models for design exploration in architecture>

11. Wikipedia ( http://en.wikipedia.org/wiki/Minimal_surface )