International Journal of Architecture, Engineering and ConstructionVol 4, No 4, December 2015, 184-192

Physics Simulation and Form Seeking in

Architecture Design Education

Ming Tang∗ and Mara Marcu

School of Architecture and Interior Design, University of Cincinnati

PO Box 210016 Cincinnati OH, 45221, USA

Abstract: This paper presents a method for integrating rule-based architectural form seeking with the aid ofdigital techniques using rules of physics and evolution. Computational methods of dynamic simulation are usedto optimize volatile solutions, through the simulation-based design process, also known as “generative design”.The paper further describes the experiential learning outcomes gained through the application of simulation asa method for solving specific design challenges. The authors focus on how a structural-based solution can evolveduring the early design stage. The research projects presented anticipate the changing variables in the designprocess and embed these variables in a “misbehaved” and “zoomable” model. Structural simulation and geneticevolution optimization tools are used to represent tectonic and building envelope variables within the parametricequation. This simulation-based process explores parametric techniques that allow for and encourage non-linearworkflows. In this process, architects do not directly manipulate a solution. Instead, various algorithms andcomputational tools are used to build a system of rules. The simulation-based design approach allows forparametric control of iterations and seeks the optimized final form and function.

Keywords: Simulation, generative design, computation, parametric design

DOI: 10.7492/IJAEC.2015.019

1 SIMULATION-BASED DESIGN

Simulation-based optimization has intrigued architec-ts through a controlled process where prior experienceis augmented by the addition of data to drive de-sign decision-making. This design process integratesinterdisciplinary analysis and evaluative processes inan automated system that assists in designing better-performing buildings. In the practice of architecture,this process is based on various generative design meth-ods such as topology optimization. Some of the emerg-ing aspects of the architectural practice involve utiliz-ing genetic algorithms in the design process, as wellas digital simulations and performance-driven designto generate complex building forms that respond topredefined rules. The use of computation within thedesign process sustains a rule-based method for mak-ing design decisions. By not being limited by a strictlinear workflow, where manually altering previous de-cisions is time-consuming and requires a regression ofthe design stage, architects are now able to establish

novel non-linear workflows where multiple design as-pects can be encoded as predefined rules. The authorsname this transformable architecture as “zoomable fo-rm” driven by physics rules and simulations. Adaptivearchitecture form allows for an adaptive method to cre-ate a constant stream of the observable field of optionsfor a design solution.

2 METHODOLOGY

Through several courses taught at the University ofCincinnati, the authors explore how simulation-basedcomputation is changing a static architectural form in-to an adaptive system that can respond to its struc-tural performance. Here, form is no longer only definedthrough Cartesian coordinates; rather it depends on amultitude of supports and applied forces. Designerstoday no longer need to view design as manipulating astatic object, but rather creating “transmutable” sys-tems that are driven by various physics rules. Two

*Corresponding Author. Email: tangmg@ucmail.uc.edu

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Figure 1. Gaudi Catenary study and physics-based form seeking (University of Cincinnati)

Figure 2. Empiric simulations: casting/hybrid analogs, vacuum forming/paper folding, and CNC routing(University of Cincinnati)

cases were introduced to illustrate the laws of physicsand their relation to architecture. The first case studyused Antoni Gaudi’s catenary simulation method to de-termine how to optimize membrane and tensile struc-tures. The second case study was the path optimiza-tion method based on Frei Otto’s wool-thread machine.Both analog models were digitally reconstructed by acomputer simulator based on the proximity and colli-sion of points, lines, and surfaces. The essential objec-tive of both case studies was to decode the analog pro-cess and migrate it to the digital simulator. Variablessuch as material properties and dynamic forces gen-erate through this process both the three-dimensional

massing and time-based media to visualize the formseeking process. (Figure 1)

Students first studied these analogue models to in-vestigate the structural and formal characteristics offabric with the intent of adapting its form to variousconstraints and different forces. The second step is thecreation of a digital simulation and the comparison ofthe results with the analogue model. The structuralperformance and material properties are calculated inthe physics engine of Autodesk Maya. Students setup the different physics rules, material properties, andcollision objects to investigate how the textile structurecan negotiate amongst these conditions.

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2.1 Zoomable World/Misbehaved Tecton-ics

In the undergraduate second year studio, we beganour working methodology through a heavily iterativeprocess that had each student choose one tectonicsystem as a precedent for the case study. As text-book, we implemented the categorization set forth byFarshid Moussavi in her book titled “The Function ofForm”. The students had to understand the systemthey started with and physically and digitally modelthe assembly to document the laws and constraints ofeach structural system. Following this introduction,the following six weeks focused on rebuilding and dig-itally remodelling each system while engaging six dif-ferent media with their implicit ways of making. Theyincluded: textile architecture, casting/hybrid analogs,3d printing, vacuum forming, paper folding, and C-NC routing (Figure 2). Students were asked to spec-ulate on how various ways of constructing mutate thechosen precedent. The exercise was sequential in na-ture, meaning that at the beginning of each processstudents departed from where they left off regardingthe development of the precedent and its associatedrepresentation. Each student was asked to build andrebuild models of the precedents and study the sys-tems through drawings and diagrams. In turn, throughthis empiric simulation, students documented variousmaterial-specific parameters and developed rules-basedmethodologies to describe each tectonic mutation.New structural hybrids have emerged through misuse

and appropriation inherent to each of the six fabrica-

tion processes (Figure 3). Students were introduced todesign methods that incorporated experimentation andthinking through making. Over the course of six weeks,students formulated their own distinct provisionalworking methodologies. Also, at the end of the process,each student arrived at a personal catalog of tecton-ic possibilities with their associated material fabrica-tion (Figure 4). The tectonic systems considered were:grids and frames (one-way frames, two-way frames, dia-grids, grid-slab frames, double-layer grids), vaults (bar-rel vaults, cross vaults, complex rib vaults, fan vaul-ts, curved rib vaults, cellular vaults), domes (surfacedomes, ribbed domes, stacked arch domes, Yazdi-Bandidomes, Kar-Bandi domes, Kaseh-Sazi domes, Muqar-nas domes), folded plates (folded plates, folded platesand trusses), shells (conical shells, umbrella columnshells, hyper curved shells), and tensile membranes(parallel cable tensile membranes, radial cable tensilemembranes) (Moussavi 2009).The resulting work was exhibited in a local gallery

owned by 3CDC, a major real estate developer in thearea. The 6” x 6” grid of artefacts was exhibited as acommentary on the current state and future possibili-ties of tectonic manifestations and on the implicationsthat technology can have on larger urban scapes. Thehighly iterative process questions the use of the “com-puter as a tool” and proposes a re-crafting of architec-ture as a starting point for the post-digital practice.The second part of the semester exposed students

to various provisional working methodologies that con-tinued the discourse generated by the obsessive initial

Figure 3. Hyper-Curved Shell I by Hannah Westendorf; Hyper-Curved Shell II by Jessica Dancer; Diagrid byMatt Miller (University of Cincinnati)

Figure 4. Permutation, Folded Plates by Paul Neidhardt (University of Cincinnati)

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indexing. Methodologies included site sensitive de-sign, precedent driven design, and operational (verbbased/spatial grammar) design. Unlike the traditionalBauhaus education, this pedagogical approach exposedbeginner students to the multiple variables and com-plexities of the sometimes irrational, highly intuitive,but mostly constrained design process. Instead of of-fering students with a set of fictitious rules, they wereexposed to various and perhaps contradicting perspec-tives that elaborated on concepts such as mat-building,field conditions and form selects function strategies.

2.2 Zoom Out: From Mat to Field

In 1914, Sant’ Elia was already rendering in his “Fu-turist Manifesto” various arrangements of planes, pub-lic spaces, stairwells and inhabitable pockets of spacewhile proclaiming that “roofs and underground spacesmust be used” and advocating for plastic dynamism(Da Costa Meyer 1995). In 1974 Alison Smithsonwas introducing in her article entitled “How to Rec-ognize and Read Mat-Building”, the taxonomy of mat-urbanism (Smithson 1974). Mat-building is an open-ended system that is inherently generative. Its ele-ments repeat at different scales, based on a dynamicand perpetual interplay of negative and positive spaces.“The cluster of parts, both interior and exterior, allowfor addition and subtraction over time. They combineto produce a built environment that is always evolving,a work in progress, remaining in the process” (MacDon-ald 2009).In architectural and urban design, mat-building be-

came visible for the first time with the actualization ofBerlin Free University in 1963 by Candilis-Josic-Woodsand the Municipal Orphanage in Amsterdam in 1960by Aldo van Eyck, and in the US with the US Air ForceAcademy in 1954 by SOM. In the definition of mat-building, the Smithsons replaced the model of the cityas a compilation of individual buildings with a wovenaggregate formed of stems which lead to clusters. Indoing so, they create a unifying mesoscale that blursthe boundaries between the architecture and the ur-ban domain. In later projects, such as the La VilletteCompetition by Bernard Tschumi and the YokohamaPort Terminal by FOA, a further development of mat-building is conceived that expands on the principlesset in the 1950’s, when the language was limited bythe manufacturing tools and processes of the day (withstandardized and rectangular elements).Exploring plastic dynamism as “a significant evolu-

tion of the rectilinear formal language of mat into amore open-ended universe of form-making”, studentswere asked to document the site through a series offield drawings that address forces such as: topography,access, and flows (MacDonald 2009). Departing fromthe latest version of the misbehaved tectonic systemstudents identified three drawing techniques for theirinvestigation, such as point-grid technique, overlapping

fuzzy domains to generate emergent subdomains, andintersecting fluids. The selection of the site, delineatedwithin what Alison and Peter Smithson would call the“charged void” of a natural and urban habitat, was leftat the students’ preference. The focus of the studiowas to perform novel and comprehensive interventionswithin rigorous assemblies of building cells and voids.The outcome is systematically engaged building andlandscape, architecture and urbanism as “autopoietic”,highly correlated and differentiated conditions (Matu-rana and Varela 1980).

2.3 Zoom In: Form Selects Function

While operating the previously defined field conditions,students were asked to make design conjectures thatmitigated between cellular units with their aggregationpatterns and larger, smoother components with theirfield conditions. The agenda was to produce muta-tions of the formerly defined misbehaved tectonic sys-tem, “understood as offerings, opportunities, potentialsrather than solutions. In that regard, we functionedon the code of novelty as the prerequisite and only em-ployed the criteria of utility and beauty as secondary,fitness testing and reassuring measures” (Schumacher2011).Our methodology involved the “form to program

heuristics, translated as form selects function instead offunction selects form” (Schumacher 2011). We oscillat-ed between the ludic and the investigative, while engag-ing post-rationalization and programmatic adaptabil-ity techniques. “Function, was here therefore under-stood as ‘capacity’ or ‘affordance’ that opens itself upto an evolutionary formation of new purposes ratherthan fulfilling a fully predetermined purpose” (Schu-macher 2011). Program was defined function of activeand passive elements. Students were asked to weavethese elements as necessary based on intrinsic [pro-gram related] and extrinsic [site related] forces. Pro-grammatic constraints were mitigated through the mis-behaved structural system. Water collection and so-lar energy harvesting, for example, were incorporat-ed through folded plate roofs and tectonic frames andgrids.

2.4 Tools

After exploring rule-based design in various case stud-ies, the method was tested in relation to structural op-timization. The objective of the project was to encour-age students to experiment with structural data anddesign a responsive solution. Long spans and tensilemembranes were studied as rule-based systems func-tion of material properties, stresses, loads, deflection,and surface tension data. The authors used a hy-brid software approach that includes Maya, solidThink-ing, Catia, Rhino, Karamba, TopOPT, and Millipedefor Grasshopper. The results were composed of com-plex structural models that were customizable based

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Figure 5. Various structure and load simulation components in solidThinking by Paul Thong (University ofCincinnati)

on rules that govern loads and supports, finite ele-ment (FE) optimization, as well as on genetic evolution(through an engine named Galapagos). This methodproved to be an invaluable resource with an unlimitedpotential for structural form exploration. (Figure 5)

Students were required to develop a sequence of it-erations that were captured to reflect the optimizationprocess. Rules such as constraints, types of supportsand materials were added to yield a matrix of struc-tural form. As a result, students created a high degreeof complexity and explored the dynamic possibilities ofform building with relatively simple rules embedded inthe parametric scripts. These codes contain buildingperformance data from surface deformation to stressloads. The encoding of parameters to construct theabstract building topology lets students easily visual-ize the inter-connection between rules and correspond-ing variations. They, consequently, learn how to inte-grate laws with numeric variables into the design pro-cess and, as a result, determine how architectural formshould adapt to above-mentioned the rules. Therefore,building forms can evolve and adapt in relation to dif-ferent load conditions.

3 PROJECTS

3.1 Form Optimization through the geneticevolution engine

For a train station design project, a long span steelframe was created without any load other than thestructure’s own weight. The maximum stress is de-termined to be an area that was high from the supportplane and relatively far from the structural piers. Thenthe structure is evaluated based on its stresses, creat-ing a more efficient system. Once the input informa-tion is used to create an assembled model, this modelis analysed for its performance. This is done using acomponent found in Karamba which is specifically de-signed to “calculate the deflections of a given model”.The “model” outputs values to visualize the deflectiondata gathered. Karamba runs a genetic evolution en-gine named Galapagos to determine the most efficientz coordinates of the surface points. The fitness val-ue appointed in Karamba is displacement. The scriptchanges the current surface to match these “fit” coordi-nates. Galapagos finds the best solution to be the most“fit” in regards to displacement, when the deflection of

Figure 6. Structural optimization through a genetic evolution engine in Karamba: 3D print conceptual modelby Mark Specker (University of Cincinnati)

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the beam system is minimum under the point loads.(Figure 6)The above images illustrate the structure concept of

a train station. The size of the pipes is defined ac-cording to the stresses shown in the diagram. Morestressed frames have a thicker cross section to providefor the support needed. The second process is to createpanels along the surface that directly respond to theintersection of the frames and the exterior skin. Gala-pagos was an integral part of the process of creatingthe most optimal form of a structural grid. After all ofthe components are set into place, and the point loadsare defined, Karamba seeks the most optimal solutionautomatically.

3.2 Material allocation

Students have investigated two simulation programsto optimize the material allocation within a definedstructural form. The software solidThinking is an en-gineering tool that shows designers how forces act ona three-dimensional structural element. Therefore, itcould be applied to produce more efficient structuralelements only by having materials located where thestress is found within the object. This allows for less-er material to be used without altering the structuralintegrity. Consequently, solidThinking became a re-search platform for the implementation of experimen-tal topology optimization procedures targeted towardsstructural design. Through an optimization process,the simulation engine analyzes a three-dimensional ob-ject, in conjunction with a series of forces and supports,

to give a user the most efficient handling of materialwithin the profile of the defined geometry. The higheststressed areas will require the most structure while thelowest stressed areas require the least amount of struc-ture. Based on this knowledge, areas are pinpointed toremove material and cut down costs.A similar tool named Millipede requires a structure

to be divided into multiple voxels so each element isevaluated on its own. We take each element’s centerand create a voxel that is dependent on a color/stress.A piece that has high stress will need the most struc-ture, so this void is smaller while a piece that has lowstress has minimal structure with a larger void. Thisprocess ensures an efficient structure in response to theload. (Figure 7)

3.3 Stress map and adaptive panels

In this case, structural performance is placed as theruling factor. Finding specific stresses in a system iskey to knowing where to strengthen it. Inputs for thesolver include supports, loads, and materials while theoutputs are more complex but include a variety stressesand material manipulations. This simulation is superi-or to an analogue process because all of the calculationsare automatic, and there is a potential to use the genet-ic evolution engine that selects the best iteration. Oncethe deflection and stress simulation results are codedinto a colour map across the geometry, they can beapplied to the original shape to seek a final, optimizedstructural and panelling system. This process is simplycomposed of evaluating which parts of the structure is

Figure 7. Finite elements analysis for material allocation based on load and deflection by Eamon Meulbroek,Zak Kolada (University of Cincinnati)

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Figure 8. Stress loads control the panels and space frame topology by Denise Polk, Zak Kolada, Kristin Plum-mer (University of Cincinnati)

truly necessary and which can be eliminated. For in-stance, a perforated surface can be re-evaluated usingthe colour map to add more structure where neededuntil an ideal surface is found. This process creates anew perforated skin that has less stress than the solidsheet would have. (Figure 8)

3.4 Synthesis

Through the recoupling of the terms “zoomable world”and “misbehaved tectonics”, concepts such as “misbe-haved world” and “zoomable tectonics” are formed,which emphasize cross-programming strategies. Thesenew terms employ the formula “form selects function”and hint at a unique, yet quasi-functional and resilientstructural system. Following this process students areasked to synthesize the two parts of the semester andpresent through their projects a possible resolution tothe zoomable world/misbehaved tectonics dichotomy.The outcome of this intensive thesis, antithesis, andsynthesis process designed to exploit a tectonic systemthat meets the needs of a specific program elicited var-ious compelling propositions (Figure 9-10). One of thestudents’ resolutions titled “Muqarnas: Misbehaved”departed from the traditional muqarna dome’s struc-tural characteristics and constraints. As a result, anew system emerged to produce a contextually high-ly correlated, yet programmatically differentiated ar-chitectural taxonomy. An educational center for post-

graduate professionals located in a forested park, thebuilding is composed of a series of faceted columns ofmodulated scales that transfer loads through stackedplates. Muqarnas: Misbehaved, therefore, distinguish-es itself from the other systems through its inherentstructural “matted” condition (Hyde 2001).The resulted field of inhabitable structural columns

negotiates within its fabric the housing of inner [withinthe column] programmatic elements and outer [with-in the labyrinthine space around the columns] greatersocial interactions (Figure 11). The ideas explored en-compass the migration of a structural precedent in-to a dramatically mutated taxonomy to maximize sitespecificity and programmatic flexibility while allowingfor instances of mutual influence to occur. While thediagram has failed to revolutionize architecture as itproved nothing else than a Beaux Arts parti, “we areleft with the difficult task to re-envision what makesform happen. Will the generation of tomorrow stillmake form or write algorithms” that generate a familyof formal possibilities calibrated to a criteria set (Picon2010)?

4 CONCLUSION

These several research projects examined approacheswhere physics laws were set and integrated into theparametric modeling pipeline to explore the potential

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Figure 9. Composite hard membranes by Sam Kissing (University of Cincinnati)

Figure 10. Membranes: misbehaved by Shinji Miyajima (University of Cincinnati)

Figure 11. Muqarnas: misbehaved by Samantha Schuermann (University of Cincinnati)

to optimize parametrically a structural solution. Theprojects extended to the spatial interaction of the rulesand their controlled objects. Form seeking was ac-complished through the exploration of several simula-tion techniques, either physics driven or evolution driv-en. The authors believe that the results expanded theboundary of conventional form seeking through rule-based form seeking. Adjacent to the topic of rule-basedmorphogenetic, the topic of simulated topological cre-ation has also influenced designers to think of form asa part within a tectonic system where the identity andposition of each element is a multiplied across a fieldof constraints. Here, the formal order of componentsis decentralized from the predetermined form and ex-clusively ordered through its relation with all other el-ements of the system. So instead of thinking of formas the center, simulation-based design has taught stu-dents to specify the process of creation before definingthe multiplicity of elements and local sources that willdetermine the formal elements’ topology. As design-ers, we, consequently, need to be methodical about thesystem of inputs we feed into a parametric utility.

Given the contemporary tectonic incertitude, we areleft to tackle the question of a working methodology

as an active, at times explosive, but - most likely -in flux notion. Within the current world of multiplic-ity, the provisional method outlined above provides,through its media engagement, for “the much-neededfiction to begin reclaiming our own freedom” (Picon2013). In the most reductive sense, the ZoomableWorld/Misbehaved Tectonic method redefined build-ing typologies as non-linear, anarchic, and nomadic.This thinking creates links between pre-existing gapswhile revealing resilient, subversive, yet rigorously tar-geted insertions in the built environment.

We can conclude that the simulation-based designprocess has created a concept of “zoomable” tecton-ics, instability and de-centralization from a static form.The paradigm in architecture has been conceived asan ideal form captured as a single entity. It wasn’tuntil architecture theorists such as Reyner and Ban-ham noted the possibilities of mutable relationshipsbetween building systems that we became critical ofthe architectural process and its outcome. Beginningwith the analog form seeking experiments by Gaudiand Otto, we can see a much more interactive processinfluencing the evolution of structural form. Withinsimulation-based design, form is now understood as a

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process of component transformation, or modulationthat behaves singularly to the specific rule it has toadapt to.

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MacDonald, J. (2009). “Reticulated form: UnitedStates Air Force Academy.” GSD Platform 2 . Ac-tar, Barcelona, Spain.

Maturana, H. R. and Varela, F. J. (1980). Autopoiesisand cognition: The realization of the living. ReidelPublishing Company, Holland.

Moussavi, F. (2009). The function of ornament. Actar,Barcelona, Spain.

Picon, A. (2010). Digital culture in architecture.Birkhäuser Architecture, Germany.

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