BEHAVIORAL STRATEGIES
SYNTHESIZING DESIGN COMPUTATION AND
ROBOTIC FABRICATION OF LIGHTWEIGHT
TIMBER PLATE STRUCTURES
Tobias Schwinn University of Stuttgart
Oliver David Krieg University of Stuttgart
Achim Menges University of Stuttgart
1 Prototype building “Landesgartenschau
Exhibition Hall.” Interior view of the timber plate
structure (Halbe, 2014)
ABSTRACT
The research described in the paper investigates the potential of behavior-based strategies, such
as Agent-Based Modeling (ABM) and behavioral form finding, to facilitate the synthesis of computational design and robotic fabrication with regards to performative lightweight timber plate
structures. In the first part, the authors provide an overview on the related topics agent systems
and planar approximation of complex geometry. In the second part, an integrative computational
design methodology is presented that enables the realization of a novel construction system for
timber plate structures including a custom robotic fabrication process. The last part of the paper
is dedicated to the architectural case study building “Landesgartenschau Exhibition Hall” that has
been designed, robotically fabricated and constructed to test and evaluate this novel computational design methodology for timber plate structures.
177
INTRODUCTION
A surprising amount of research and development has been dedicated in recent years to one of the oldest available building materials: wood. Innovation in fabrication technology, recent changes in
building code and regulations, explorations in high-rise construction and innovative new building products have led to what can
be termed a renaissance of timber construction (Fountain 2012).
Certainly, as a renewable resource, and given its negative carbon
footprint and low embodied energy (Alcorn 1996; Kolb 2008), wood
plays a central role in the current discourse on carbon-neutral, energy- and resource-efficient construction.
However, in many regions timber is also a limited resource, as
the forests fulfill a number of conflicting socio-economic and
2
Fabrication and construction. A. Robotic fabrication of a plywood plate with
large-scale finger joints. B. Assembly of the novel, lightweight timber plate
structure prototype. (ICD/ITKE/IIGS University of Stuttgart 2014)
ecologic roles. Protection of natural habitats, invaluable spaces for
recreation and economic considerations of investment and return
application in architecture has to involve structural performance cri-
can place a considerable pressure on forests. In this context of
teria and the specific constraints of material, fabrication and build-
growing demand and limited supply, strategies are needed that
ing technology (Figure 2). As part of the ongoing research into light-
are able to negotiate the conflicting benefits of increasing tim-
weight timber plate structures, a novel behavioral design approach
ber construction on the one hand, but minimizing the volume of
is introduced in this paper that addresses the following goals:
wood exploitation on the other. One strategy is to reuse off-cut or
reintroduce it into the material cycle. Another is to decrease the
ratio of self-weight to load-bearing capacity and, consequently, to
(1) solve the polygonal subdivision of complex, doubly curved
geometries using planar building elements;
increase the structural performance. A methodology to implement
(2) synthesize computational design and robotic fabrication in
the latter is lightweight construction.
a coherent digital design approach; and
(3) integrate the demands of a fully enclosed, insulated and
The research presented in this paper is part of an ongoing effort to
waterproof building.
design and develop resource-efficient lightweight structures and
their corresponding fabrication procedures, and to demonstrate
their performance through prototype buildings (Figure 1). In the con-
CONTEXT AND RELATED WORK
text of lightweight construction, plate structures are of particular
One of the indisputable and at the same time intangible qualities
interest as they are exceptionally performative from a structural
of architecture is that it constitutes more than the sum of its parts.
point of view: they can be organized such that the individual plates
Nevertheless, buildings are essentially assemblies of a vast array
constitute the primary load bearing structure, instead of the joints
of individual elements that interface with their respective neigh-
(Bagger 2010). Previous research showed that an integrated, perfor-
mance-driven computational design process is paramount to the
development of a performative architectural timber plate structure
(La Magna et al. 2013; Schwinn, Krieg and Menges 2012). Such a pro-
cess requires the synthesis of design and fabrication, so that the
rules and constraints of a specific fabrication setup can inform the
design process. The morphospace of a particular fabrication setup
provides the conceptualization for integrating machine control into
the design domain and, reciprocally, design information into the
machine domain (Menges 2012).
bors through joints and connections. This interfacing is predicated
on the rules and constraints that are inherent to the building
elements themselves. In other words, embedded in each component, be it beam, column, panel, wall or window, are well-defined
functional, material, fabricational and assembly logics. The prospect of this research, therefore, is that locally defined rule sets,
which are inherent to each building element, can be utilized in
a bottom-up approach for negotiating the shape and location of
these elements within the larger context of an assembly according to well-defined performance criteria. This hypothesis is being
investigated with regards to the bottom-up, rule-based formation
One of the challenges involving plate structures, however, remains
of finger joint timber plate structures using agent-based modeling,
the tessellation or approximation of non-trivial geometry through
a computational approach for locally integrating constraints into a
planar subdivision. Beyond an exercise in computer graphics, an
system of multiple interacting parts.
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3 Tangent plane intersection for doubly curved surfaces. Oscullating circles indi-
cate curvature (1/R), principal curvature directions and orientation. A. Synclastic,
positive Gaussian curvature K > 0. B. Anticlastic, negative Gaussian curvature
K < 0. (ICD/ITKE/IIGS University of Stuttgart 2014)
AGENT-BASED MODELING
Agent-based modeling (ABM) is a computational methodology for design, simulation, optimization and decision making that is utilized in a variety of fields including robotics, finance, logistics, computer games, sociology and biology—in other words, whenever many individuals interact with each other and the environment according to locally defined rules. Very often this
process exhibits a form of emergent self-organization that does not require centralized control
mechanisms (Ball 2012). Example applications of ABM in the architectural and urban planning
context are the simulation of pedestrian movements in urban environments, simulation of
building evacuation and design exploration. Recent applications include ABM for integrating
fabrication constraints into the design process (Baharlou and Menges 2013). Being an example
for behavior-based artificial intelligence (Brooks 1986), in each of these application scenarios,
the premise is that ABM can simulate and solve complex optimization problems involving
multiple locally interacting entities.
Current implementations of agent-based systems such as the one by Shiffman in Processing (1)
are to a large extent based on a model developed by Craig Reynolds in the 1980s and 1990s
(Shiffman 2012). One of the key features of Reynolds’s model is the ability of autonomous vehi-
cles, a concept borrowed from Braitenberg, to reposition and reorient based on internal rules
and external stimuli exhibiting a form of collective behavior (Reynolds 1999; Braitenberg 1984). The
vehicles have a limited ability to perceive their environment, including fellow vehicles, and adjust
their movements according to their pre-defined goals. Besides locomotion, the main aspect of
Reynolds’s model is the definition of steering rules that provide the agents with improvisational, life-like collective behaviors. While the behaviors described by Reynolds are mainly geared
towards computer gaming and character animation, the fundamental individual behaviors such
as seek, arrival, containment and flow field following and group behaviors such as cohesion,
separation and alignment can provide the basic building blocks for the further development with
regards to plate systems.
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SCHWINN, KRIEG, MENGES
BEHAVIORAL STRATEGIES
PLANAR SUBDIVISION
Approximation of complex, doubly curved surfaces through planar
subdivision is a topic in computational geometry that is actively
especially beneficial for the structural behavior of plate structures
(Wester 2002; Bagger 2010; La Magna et al. 2013). Consequently, TPI is
implemented as a property of each agent in the agent system.
being researched in the fields of computer graphics (low poly
representation of large data sets, for example produced by 3D
scanning) and architectural geometry (optimization of complex geometry for fabrication). Strategies of varying complexity are investigated in the literature, each of which has its specific application
scenario but also distinct limitations. A recurring theme, however,
are variations of the tangent plane intersection method (Troche
2008; Wang et al. 2008; Manahl, Stavric and Wiltsche 2012; Zimmer et
al. 2012). Tangent plane intersection (TPI) has a number of useful
AGENT-BASED MODELING FOR PLATE
STRUCTURES
The agent-based modeling approach for plate structures relies on the
calculation of a steering force for each agent based on its individual
behaviors. These behaviors address a variety of goals related to global
design parameters, such as the number of plates, average plate size
or structural performance and to local design parameters.
characteristics that also make it applicable in the context of agentbased modeling for plate structures.
First, the intersection points of a plane T0 with its neighboring planes
can be constructed unambiguously without the need for a computationally expensive iterative approximation. Second, these intersection
points, which define the vertices of the polygon, are guaranteed to
lie in the original plane T0 (Figure 3). Third, the method is equally robust on synclastic and anticlastic surfaces. In parabolic areas however, that is in areas where the Gaussian curvature K approaches zero,
the intersection points of nearly parallel planes might be extremely
far from the input points, resulting in degenerate polygons. A second
challenge of the TPI method is the need to determine which tangent
plane intersects with which other planes nearby in order to generate
valid intersection points. Therefore, for each plate the notion of a
neighborhood has to be introduced in order to define which of the
resultant planar polygons will share an edge. Wang et al. and Troche
address this task by introducing a duality, which states that for
each planar, polygonal subdivision exists a corresponding triangular
4a Parameters of the morphospace as agent behaviors: Plate angle-based agent
behavior (ICD/ITKE/IIGS University of Stuttgart 2014)
representation. The main effort in this approach then becomes the
generation of a valid triangulation. While the two methods suggested by the authors, the conjugation method (Wang et al. 2008) and the
advancing front method (Troche 2008), are responding to the local curvature of the underlying geometry and produce meaningful results
for some types of doubly curved surfaces, they only allow indirect
control of the plate sizes and other fabrication constraints. Manahl
et al. try to address the same issues with a focus on ornamental
panelizations by giving the designer more control over the individual
plate geometries through a point grid controller (Manahl et al. 2012).
However, with a rising number of elements and manipulations the
process quickly becomes impractical.
It is important to note that the duality between triangulation and
planar subdivision is such that in the polygonal result, three polygons will always share one vertex (3-valency). Wester, Bagger,
La Magna and others have shown that this configuration is
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4b Parameters of the morphospace as agent behaviors: Edge-based agent behavior
with underlying change-of-curvature vector field
(ICD/ITKE/IIGS University of Stuttgart 2014)
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and subsequent edge flipping of the 3D mesh based on shortest
Cartesian distance to define plate adjacencies (Troche 2008). As
described above, the intersections of the three tangent planes TN
at the vertices of each triangle adjacent to T0 define the vertices
of the agent’s plate (Figure 3).
BEHAVIORS BASED ON THE MORPHOLOGY
OF THE PLATES
The steering forces are calculated based on the local plate morphology. Attributes of the plate-agent model are plate size (radius of the
circumscribing circle), plate edge lengths, plate angles between
adjacent plates and planarity. The definition of what is a desirable
5a Change-of-curvature vector field with vectors pointing towards decreasing
absolute Gaussian curvature. A. Synclastic surface (ICD/ITKE/IIGS University of
Stuttgart 2014)
plate morphology and the valid ranges for the attributes’ values are
primarily based on the fabrication and construction parameters:
sizes of the stock material and machine dimensions determine the
maximum polygon radius; joint type and joint fabrication strategy
determine the minimum and maximum allowable angle between
plates and the range of allowable edge length. Secondarily, this
definition is also based on aesthetic considerations, for example,
similar edge proportions and symmetry within the plate.
Following are two examples for plate behaviors: First, the angle between adjacent plates is a function of the distance between agent
locations and of the amount of curvature at the agent locations:
decreasing the distance between plates will also decrease the
angle between them. Second, in the case of an asymmetrical plate
outline with large changes in edge lengths the location of the agent
will be away from the weighted edge centroid of its plate: moving
5b B. Surface with both synclastic (red and yellow) and anticlastic (cyan and blue)
regions separated by the parabolic line, where K=0. (ICD/ITKE/IIGS University of
Stuttgart 2014)
the agent towards the edge centroid will result in a symmetrical
plate outline.
BEHAVIORS BASED ON THE PROPERTIES
OF THE ENVIRONMENT
These local parameters are directly related to the constraints of material and fabrication: in order to generate producible plates, their geometric attributes have to lie within the given machinic morphospace.
The behaviors translate the given goals in terms of repositioning and
reorienting the agents tangentially along the surface. A crucial aspect
in the translation of goals into motion behaviors is the definition of the
appropriate individual actions that lead to a global planar configuration.
IMPLEMENTATION
DEFINING THE NEIGHBORHOOD
The specific plate outline of each agent is not only a function of the
topology of the agent system and the distances between agents,
but also based on the properties of the environment that the agent
model inhabits. Specifically the local curvature has an effect on the
plate outline: convex in K>1 areas, non-convex in K<1 areas, which
results in the characteristic bow-tie shape in the case of a hexagon.
The local curvature change, represented by a vector field (flow field)
with the vectors pointing in the direction of decreasing curvature, is
used in a behavior that drives the vehicles into areas of increasing
The agent locations define the input point set for the tangent
absolute curvature, avoiding parabolic areas (Figure 5). A second
plane intersection. The neighborhood of each agent is defined
behavior related to the environment insures that the agents remain
using a Delaunay triangulation of the parameter value set (u, v)
within the boundary of the environment (containment).
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SCHWINN, KRIEG, MENGES
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6
Synclastic surface regions. A. Plates based on randomly distributed input points. B. Plates based on ABM (ICD/ITKE/IIGS University of Stuttgart 2014)
DEALING WITH EXCEPTIONS
As described above, the TPI method produces invalid results in
parabolic areas, that is in areas where K approaches 0. Therefore, a
mechanism has been devised to deal with the cases where degenerate polygons are generated. First, what constitutes a degenerate
polygon has to be defined by some boundary condition or threshold
value. Empirically, it has been found that a test for inclusion is a useful threshold for stating if a polygon will be invalid: if the projection
I’ of the intersection point I (of the tangent planes of a triangle) onto
plane T of the triangle lies outside its circumcircle C, then the intersection I is considered invalid and the point is projected onto the perimeter of C. The resultant polygonal outline is clearly non-planar but
the adjacent polygons will still be able to share the same vertex. Each
agent therefore has two modes of operation: (1) with a valid plate,
in which the steering is based on the properties of the plate, and
7a Anticlastic surface regions. Plates based on randomly distributed input points
(ICD/ITKE/IIGS University of Stuttgart 2014)
(2), without plate (but with polygonal non-planar outline), where the
steering is geared towards acquiring a valid plate. Once the agent
has acquired a valid plate it will switch modes and try to improve its
plate’s characteristics using the behaviors defined in mode (1).
RESULTANT BEHAVIORS
The resultant behavior of each agent in the system is a negotiation of
the multiple goals and behaviors described above. However, in order
to achieve the high-level goal of an aesthetic, structurally performing
and producible plate structure, the steering force of each agent
cannot be calculated simply based on a weighted average of all its
behaviors as some behaviors might cancel each other out (Reynolds
1999). Instead, a prioritized approach has been chosen based on the
ordered sequence of containment, planarity and plate behaviors.
In the development stage, the ABM approach was continuously
7b Plates based on ABM (ICD/ITKE/IIGS University of Stuttgart 2014)
tested on generic case studies as a proof-of-concept.
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individual joint geometry. As described above, each parameter
can be described with maximal, minimal and optimal values towards which the agent-based simulation is aiming.
FABRICATION PARAMETERS
OF LARGE-SCALE FINGER JOINTS
In previous research different types of robotically fabricated finger
joints have been developed for specific structural and architectural
tasks (Schwinn, Krieg and Menges 2012; Krieg and Menges 2013). It was
shown not only that the individual plates in a plate structure can
be arranged in a way so that they are the primary load bearing
elements, but also that the structural stability is based on distributed in-plane shear forces along the plate edges (Bagger 2010),
thus making teethed and interlocking connections, such as finger
8 Large-scale finger joints. A. Physical prototype of a plywood timber plate that
includes extended functionalities to meet requirements of on-site assembly and
building codes. B. Different parameters control the finger joint geometry and cross
fitting screw connection details. (ICD/ITKE/IIGS University of Stuttgart 2014)
joints, particularly suitable (Figure 8).
In the presented research project and corresponding case study, a
large-scale finger joint connection is part of the development of an
integrative digital design and fabrication process for lightweight
and large-scale plywood plate structures. The constructional
Specifically, it was tested in different environments, such as syn-
details and robotic fabrication process are developed in close
clastic (Figure 6), anticlastic (Figure 7) and parabolic regions. In order
relation with the machine setup (machinic morphospace) involving
to evaluate the efficacy of the approach, the ABM solution was
workspace and boundary conditions, such as stock material, and
compared to a random distribution of input points, the TPI method
building part handling and assembly.
being the same in both cases. The result shows that the high-level
agent behavior optimizes the plate morphology and distribution
with respect to the performance criteria stated above. However,
it was also shown that in the current implementation and state of
development, the system might fail to converge to a stable solution in the parabolic areas. For this case, and in order to expedite
the generation of a valid solution, a post-process was developed
that forces planarity through an optimization method, minimizing
non-planarity, similar to Wang et al. at the cost of a less optimal
plate morphology (Wang et al. 2008).
A special focus in the development of three-dimensional finger
joints lies on construction and assembly details, especially in the
context of negative Gaussian curvature areas. The finger joints’
functionality is extended to meet requirements of on-site assembly as well as building codes for connecting plywood plates under
different structural load conditions. This leads to the implementation of both, assembly-related functionalities such as screw
pockets and plate insertion vectors, as well as constructional
details such as cross-type screw fittings. The integration of these
additional functionalities is achieved using a generative parametric
One approach to address the convergence problem will be to
design methodology, making every detail adaptable to local and
allow additional degrees of freedom for the agents on the surface.
global parameters (Figure 9).
Similar to Zimmer et al., this might include freeing the agents’
plate normal vectors from being oriented strictly normal to the
orient away from the tangent plane would provide more degrees
DATA MODEL
AND MACHINE CODE INTEGRATION
of freedom and allow the system to converge to a valid solution.
A computationally lightweight boundary representation (B-rep)
surface (Zimmer et al. 2012). In such a way, normal vectors that can
model generated by the agent system geometrically represents
ROBOTIC FABRICATION OF FINGER JOINTS
the plate distribution. Throughout the whole digital design and
fabrication process, no more geometry information than the sur-
The synthesis of the material’s design space and the machinic
face representation is needed. The model maintains a topological
morphospace is reflected by a group of process-specific param-
database of the connectivity between all plates and edges includ-
eters, ranging from the available plywood stock material to the
ing a numeric representation of all plates, their adjacent edges
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SCHWINN, KRIEG, MENGES
BEHAVIORAL STRATEGIES
9 Milling cycles. Position and orientation of the tool is calculated in relation to the normal vectors of two
adjacent plates and their shared edge. A. Roughing and finishing. B. Pockets. C. Spot facing (ICD/ITKE/
IIGS University of Stuttgart 2014)
and neighboring plates, as well as their connection angle (Figure 10A). Subsequent modeling steps,
such as material thickness, joint geometry, and tool path generation, only depend on the topology
information as a basis and data structure template.
Tool-paths can be generated without any further geometric information (Figure 10B). In fact, the solid
plate model itself is generated from the tool-path information and only needed for visualization and
quantity takeoff purposes (Figure 10C). Based on the topological surface representation of the plate
arrangement, tool-paths are generated mainly through trigonometry operations using geometric parameters such as the connection angle between two adjacent plates, their shared edge’s length and
user parameters, such as material thickness and joint size. Several categories of tool-paths are subsequently generated that can also be adapted during the fabrication process to meet certain tolerance
criteria (Figure 9). Besides the tool-paths for roughing and finishing the plate’s three-dimensional contour, auxiliary tool-paths are generated for constructional details such as cross-type screw fitting pockets, spot facing areas and drilling tool-paths. The subsequent simulation of the 7-axis robot kinematics
for fabricating the plates is directly linked to the machine code generation. With the use of a turn table
as an additional axis, the simulation provides control over the robot and turn table movement and
exports ISO-compliant machine code for KUKA.CNC (2) that can directly be read and executed by the
robotic setup without further file format translations (Figure 11).
CASE STUDY AND RESULTS
In order to demonstrate the flexibility and adaptability of the agent-based modeling approach on a
large-scale prototype building, a computational form finding method was developed for generating the agent system’s environment that integrates the system’s requirements for doubly curved
geometries. The design space at which the development is aiming can be seen as an intersection
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10 The tool-paths for the robotic fabrication of a plate are generated from the topology analysis of a surface model (ICD/ITKE/IIGS University of Stuttgart 2014)
tool in the design process possible. Examples of the latest developments in this field are the Thrust Network Analysis method,
which allows the design of compression-only networks (Lachauer,
Rippmann and Block 2010), as well as hanging chain models, which
are part of the force density method based on the force-length ratios defined for individual elements of a net structure (Schek 1974).
Both methods’ basic principle of force simulation is used for the development of a custom digital design approach, integrating particle
spring-based form finding, as well as additional external, force-driven design inputs that can react to boundary conditions such as an
architectural context and program. By employing additional local
controllers that act as design forces in the realm of physical simulation, the design tool finds a force equilibrium between top-down
design inputs and catenary form.
11
Robotic fabrication setup. Simulation of fabrication process and robot control
code generation (ICD/ITKE/IIGS University of Stuttgart 2014)
This method shows particular advantages for construction systems
that do not depend on compression-only geometries, such as 3-valent plate structures, and widely extends the design space while
between global geometry parameters, structural optimization
still pursuing a structurally informed solution at all times during the
and boundary conditions of the ABM strategy as well as the fab-
simulation.
rication process. To meet these requirements, the computational
form finding tool aims at a structurally informed global geometry
while also responding to top-down design inputs.
COMPUTATIONALLY DEVELOPING
AN ENVIRONMENT FOR AGENT SYSTEMS
This process also allowed the control of double curved surfaces,
which inherently perform better than surfaces with Gaussian
curvature approaching 0. This applies for structural optimization
as well as for the plate structure system itself, whose individual
plate geometry directly depends on the local curvature. In the pre-
Physical form finding for structural optimization has been devel-
sented case study, the custom digital design approach used an
oped and used throughout the 20th century. Today, computation-
iterative process for the adaptation of the global geometry to local
al methods make physical simulations as a digital form finding
plate parameters and vice versa (Figure 12).
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SCHWINN, KRIEG, MENGES
BEHAVIORAL STRATEGIES
12
Global plate morphology in relation to Gaussian Curvature. A. The custom digital design approach is a synthesis of bottom up form-finding and top-down design inputs
in order to adapt to spatial and geometrical parameters. B. Resultant plate arrangement of the ABM method on the basis of the generated surface environment. (ICD/
ITKE/IIGS University of Stuttgart, 2014)
1 3 Interior views. A. The computationally generated fabrication data model. (ICD/ITKE/IIGS University of Stuttgart, 2014)
B. The prototype building at the Landesgartenschau. (Halbe, 2014)
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LARGE-SCALE PROTOTYPE BUILDING
CONCLUSION
The developed integral computational design and digital fab-
The research presented in this paper demonstrates the synthesis
rication method for timber plate structures was applied in the
of computational design and digital fabrication through agent-
context of a large scale prototype building built as part of the
based modeling in the context of a large-scale prototype building.
Landesgartenschau in Schwäbisch Gmünd, Germany, in 2014
It shows that, while the development of a robotically fabricated
(Figure 13). Named the Landesgartenschau Exhibition Hall, the pro-
finger joint plate structure is an essential part of lightweight timber
totype is a fully enclosed, insulated and waterproof building that
construction, agent-based modeling strategies enable a highly dif-
hosts an exhibition during the Landesgartenschau and will serve
ferentiated structural and architectural performance. Through the
as an event space afterwards. The plate structure system is con-
implementation of agent behavior based on plate morphologies,
structed using locally available beech plywood, the availability of
the design process integrates fabrication constraints and plate
which is in line with the future regional foresting strategies.
structure characteristics. Here, the design process is informed by
the robotic fabrication technique, and vice versa.
The developed process includes all stages of fabrication for all
construction layers of the plate structure, starting from the automated machine code generation for cutting stock pieces on a
Hundegger Speed-Panel-Machine, and the generation of the robotic fabrication code for the KUKA.CNC language (ISO 6983), to
the fabrication data for water-jet cutting the waterproofing EPDM
layer and CNC milling the wood fiber insulation and the larch plywood cladding layers. Consisting of 243 prefabricated polygonal
modules, the case study building exhibits exceptional lightweight
characteristics as its structural beech plywood layer is only 50 mm
thick and spans almost 10 meters. Overall, a usable floor area of
125 m² and a gross volume of 605 m³ is enclosed by 12 m³ of
beech plywood, resulting in a structural weight of only 37.9 kg/m²
of the shell (Figure 14). In line with the overall goal of maximizing
the utilization of the available building material, the cut-off generated by the cutting of the stock pieces could be reused in the
ACKNOWLEGEMENTS
The work presented in this paper was partially funded by the
European Union through the European Fund for Regional
Development (ERDF) and the state of Baden-Württemberg through
the “Clusterinitiative Forst und Holz” program and is part of a
joint research project between the University of Stuttgart and
Müllerblaustein Holzbau GmbH. The authors would like to express
their gratitude towards their fellow investigators, Prof. Jan Knippers
and Jian-Min Li at the Institute for Building Structures and Structural
Design (ITKE), and Prof. Volker Schwieger and Annette Schmitt
at the Institute for Geodesic Engineering (IIGS), University of
Stuttgart. The authors would also like to thank their project partners
Müllerblaustein Holzbau GmbH, Landesgartenschau Schwäbisch
Gmünd 2014 GmbH, ForstBW and KUKA Roboter GmbH.
hardwood flooring as lamellas of the parquet.
14 Material utilization. The Exhibition Hall’s volume of 605 m³ is enclosed with only 12 m³ of beech plywood resulting in a self-weight to shell surface area ratio of
37.9 Kg/m² (ICD/ITKE/IIGS University of Stuttgart 2014)
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IMAGE CREDITS
Figure 1–13A, 15. ICD/ITKE/IIGS University of Stuttgart.
Figure 13B & 14. Halbe, Roland (2014).
Lachauer, Lorenz, Matthias Rippmann, and Philippe Block. 2010. “Form
Finding to Fabrication : A Digital Design Process for Masonry Vaults.” In
Proceedings of the International Association for Shell and Spatial Stuctures (IASS)
Symposium 2010. Shanghai.
Manahl, Markus, Milena Stavric, and Albert Wiltsche. 2012. “Ornamental
Discretisation of Free-Form Surfaces.” International Journal of Architectural
Computing 10 (4) (December 1): 595–612.
Menges, Achim. 2013. “Morphospaces of Robotic Fabrication.” In
Robotic Fabrication in Architecture, Art and Design: Proceedings of the Robots in
Architecture Conference 2012, edited by Sigrid Brell-Çokcan and Johannes
Braumann, 28–47. Vienna: Springer Wien New York.
Kolb, Josef. 2008. Systems in Timber Engineering: Load-Bearing Structures and
Component Layers. Basel: Birkhäuser.
TOBIAS SCHWINN is research associate and doctoral
Krieg, Oliver David, and Achim Menges. 2013. “Potentials of Robotic
Fabrication in Wood Construction.” In ACADIA 13: Adaptive Architecture
[Proceedings of the 33rd Annual Conference of the Association for Computer
Aided Design in Architecture (ACADIA)], edited by Philip Beesley, Omar Khan
and Michael Stacey, 253–260. Cambridge, Ontario.
candidate at the Institute for Computational Design (ICD) at the
University of Stuttgart, Germany. In his research he is focusing on the
integration of robotic fabrication and computational design processes.
Prior to joining the ICD in 2011, he worked as a Senior Designer for
Skidmore, Owings and Merrill in New York and London.
La Magna, Riccardo, Markus Gabler, Steffen Reichert, Tobias Schwinn,
Frédéric Waimer, Achim Menges and Jan Knippers. 2013. “From Nature
to Fabrication : Biomimetic Design Principles for the Production of
Complex Spatial Structures.” International Journal of Space Structures 28 (1):
27–39.
OLIVER DAVID KRIEG is a research associate and
Reynolds, Craig W. 1999. “Steering Behaviors For Autonomous
Characters.” In Proceedings of Game Developers Conference, 763–782.
Schek, H.-J. 1974. “The Force Density Method for Form Finding and
Computation of General Networks.” Computer Methods in Applied
Mechanics and Engineering 3 (1) (January): 115–134.
doctoral candidate at the Institute for Computational Design at the
University of Stuttgart. He has worked as a Graduate Assistant at the
institute’s robotic prototype laboratory “RoboLab” since the beginning
of 2010. In the context of computational design his research aims to
investigate the architectural potentials of robotic fabrication in wood
construction.
ACHIM MENGES is a registered architect and professor
Schwinn, Tobias, Oliver David Krieg and Achim Menges. 2012.
“Robotically Fabricated Wood Plate Morphologies.” In Robotic Fabrication
in Architecture, Art and Design, edited by Sigrid Brell-Çokcan and Johannes
at the University of Stuttgart where he is the founding director of
the Institute for Computational Design. His work focuses on the
development of integrative design processes at the intersection of
morphogenetic design computation, biomimetic engineering and
robotic fabrication.
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