Design and construction principles in nature and architecture

Abstract

This paper will focus on how the emerging scientific discipline of biomimetics can bring new insights into the field of architecture. An analysis of both architectural and biological methodologies will show important aspects connecting these two. The foundation of this paper is a case study of convertible structures based on elastic plant movements.

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Design and construction principles in nature and architecture
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IOP PUBLISHING BIOINSPIRATION &BIOMIMETICS
Bioinspir. Biomim. 7 (2012) 015002 (10pp) doi:10.1088/1748-3182/7/1/015002
Design and construction principles in
nature and architecture
Jan Knippers
1,2,3,4,6
and Thomas Speck
2,3,5
1
Institute of Building Structures and Structural Design (ITKE), University of Stuttgart, Stuttgart,
Germany
2
Competence Network Biomimetics, Baden-W
¨
urttemberg, Germany
3
Bionics Competence Network (BIOKON eV), Germany
4
Knippers Helbig Advanced Engineering, Stuttgart, Germany
5
Plant Biomechanics Group Freiburg, Botanic Garden, Faculty of Biology, University of Freiburg,
Freiburg, Germany
E-mail: j.knippers@itke.uni-stuttgart.de
Received 19 July 2011
Accepted for publication 29 November 2011
Published 16 February 2012
Online at stacks.iop.org/BB/7/015002
Abstract
This paper will focus on how the emerging scientific discipline of biomimetics can bring new
insights into the field of architecture. An analysis of both architectural and biological
methodologies will show important aspects connecting these two. The foundation of this paper
is a case study of convertible structures based on elastic plant movements.
(Some figures in this article are in colour only in the electronic version)
1. Introduction
Architects and master-builders have been using nature as a
source of inspiration long before the terms bioinspiration or
biomimetics were introduced. The eras in which architects
transferred the variety of natural shape and form directly into
their work alternated with those of strict geometrical order.
After a period of technological functionalism and subsequent
post-modern architecture, today’s aesthetic understanding is
focused once more towards movement and flowing spaces
which reflect forms found more or less directly in nature.
Which new findings can this young scientific discipline
biomimetics offer architecture? New options can only result
from an in-depth analysis and comparison of architecture and
nature, both from a broader and deeper perspective as well as
on a functional and methodological level. Not only architects
show a deep interest in this discussion, also biologists are
actively pursuing their interest in architectural design (Gould
and Lewontin 1979).
Architectural design and biological evolution are non-
deterministic processes. In biological evolution and
architectural design, evaluation criteria and development
targets are created and are part of a process subject to
6
Author to whom any correspondence should be addressed.
constant change and adaptation. In this respect, biology and
architecture differ from most engineering sciences, which
usually concentrate on the optimization of clearly defined
individual functions with fixed boundary conditions and target
functions. In architecture, a quantifiable optimum is, at its best,
only possible with some technical or economical parameters
(e.g. optimization of energy or material consumption), but
it does not allow for an integrated assessment of important
features such as aesthetic, spatial, urban or social qualities,
which are vital for successful and sustainable architecture.
During the course of evolution, biological organisms
adapted their character through selection and interaction
to meet constantly changing environmental conditions by
developing multifunctional solutions. The result is a
compromise satisfying partially conflicting requirements
(Rowe and Speck 2004, Speck and Rowe 2006). In this
context, it is worth mentioning that living beings carry
an ‘evolutionary burden’ because evolutionary innovations
always build on inherited structures (the ‘bauplan’) and their
respective functions. The ‘bauplan’ and the fact that living
beings have to ‘function’ successfully during all phases of
evolution confine the potential of natural selection as an
optimizing agent. A comparable situation can be found in
architecture, where a building plan based on static constraints
1748-3182/12/015002+10$33.00 1 © 2012 IOP Publishing Ltd Printed in the UK

Bioinspir. Biomim. 7 (2012) 015002 J Knippers and T Speck
Figure 1. Five different structural hierarchical levels of plant stems covering up to 12 orders of magnitude, shown as an example in a pine
stem and a tracheid. Adapted from Speck and Rowe (2006).
confines the degree of freedom of further architectural
embodiment. Therefore, similar to architectural design,
evolutionary adaption in nature is limited by ‘architectural’
constraints predetermined in the ‘bauplan’ of the biological
organism (Gould and Lewontin 1979).
The requirements modern buildings have to fulfil today are
very complex, often contradictory, and during their life cycle
need to be adapted for utilization, economical and ecological
reasons. In the last decades, emerging ecological demands
have been a driving force in the development of highly
evolved building technologies including material development
and automation. Nonetheless, these technologies are still
handled as isolated components which are integrated into
otherwise traditional building concepts.
Holistic approaches for new structural, functional and
ecologically efficient buildings may be expected from a more
interdisciplinary approach. A very important aspect will be
an effective exchange of research between the disciplines,
not only on the level of scientific knowledge but also on a
methodological level. Biology is in this respect of particular
interest for architects and civil engineers, since it delivers
not only isolated phenomena but also new technical and
methodological strategies.
2. Design and construction in nature and
architecture
In addition to the initially drawn parallels, fundamental
differences between architecture and biology can also be
identified. Taking these differences into consideration can lead
to a change in perspective and to an expansion of possibilities
for architects and engineers.
If we restrict ourselves to considering structures in biology
and architecture, it becomes apparent that, in respect of
structural design, they have diametrically opposite principles.
Architecture and civil engineering define construction in two
categories: ‘material’ and ‘structure’. In today’s practice,
the design of a structure is a hierarchical process. It starts
with the choice of a load-bearing system. This is based on
a limited canon of options (e.g. beam, truss, wall, slab, arch,
etc) that are primarily classified through analysis as well as
construction methods. Such support systems are realized in
very similar forms but using different materials which are
selected during the second stage (e.g. steel, timber, masonry
or concrete, etc). Natural constructions, however, arise from
an almost infinite diversity through mutation, recombination
and selection. They show a hierarchical structure on usually
five to seven levels that may span up to twelve orders of
magnitude (Dunlop and Fratzl 2011, Fratzl and Weinkammer
2007,Milwichet al 2006, 2008, Speck and Rowe 2006).
A conifer stem shows (at least) five different structural
hierarchical levels (figure 1). On each of these hierarchical
levels, which cover up to twelve orders of magnitude,
the different functionally important properties of the
stem (including mechanical properties such as stiffness,
damping and prestressing; water and assimilated transport;
nutrient storage; adaptive growth by reaction wood, self-
repair; heat insulation, etc) may be varied (Speck and Burgert
2011). Mechanical properties for example can be influenced
on the biochemical level by the cellulose-to-lignin ratio, on
the ultrastructural level by the angle of cellulose microfibrils,
on the microscopic level by the cell wall thickness (mainly the
thickness of the S2-layer) and the distribution of pits, on the
macroscopic level by the ratio of early wood to late wood, and
on the integral level by the amount of secondary wood.
From the macroscopic organism down to the smallest
molecular components, each structural element consists
of smaller sub-structures made up of similar building
components. A separation into ‘material’ and ‘structure’
categories is therefore not possible (figure 1). The same
2

Bioinspir. Biomim. 7 (2012) 015002 J Knippers and T Speck
(a)(b)
Figure 2. (a) Geodesic Dome Montreal 1967, Buckminster Fuller (photo: Philip Hienstorfer). (b) Grid Shell Frankfurt MyZeil, Architect:
M Fuksas, Rome; Engineer: Knippers Helbig Advanced Engineering (Knippers and Helbig 2007, 2009; photo: Christian Sauter).
applies to the terms ‘structure’ and ‘form’, which are of great
importance in architecture. The various functions of a thermal
envelope, spatial separation, building services, load transfer,
etc are assigned to different components. Consequently, the
load-bearing ‘structure’ and the space-shaping ‘form’ of the
building are functionally separated. In an architecture that is
driven by formal aesthetics, the geometric ‘form’ is often not
even related to the geometry of the ‘structure’.
In natural structures, however, the basic building
components not only support the structure but also carry
substances that catalyze chemical reactions and recognize
molecular signals. The ‘form’ arises from functional
requirements that are met by a ‘structure’ which is often
composed of a single basic substance.
From an engineering perspective, the analysis of natural
structures demonstrates that they essentially consist of a small
number of mostly light elements (C, H, O, N, P, S, P, Ca,
etc) and only a few polymeric substance groups (proteins,
polysaccharides, lipids, nucleic acids, etc) exist (Dunlop
and Fratzl 2010, Fratzl and Weinkammer 2007, Jeronimidis
2000a, 2000b,Milwichet al 2006, Speck and Rowe 2006).
Individual cells form tissues that are combined to create
‘organs’ with different functions. Natural structures are
often not isotropic but consist of fibres such as cellulose or
collagen with direction-dependent properties. By combining
different trajectories and the packing density of fibres, a
number of finely tuned structural properties is achieved.
In addition, chemical and structural heterogeneities play an
important role in allowing local adjustments to be integrated.
The continuous external skeleton (exoskeleton) of insects,
for example, is made from chitin fibres (polysaccharides)
which are embedded in a protein matrix. The chemical,
structural and mechanical properties of such a composite
material may vary to a large extent and thereby allow for
local functional adaptations in different areas of the insect’s
body. Natural constructions, therefore, consist of only a
few basic components which are geometrically, physically
and chemically differentiated. In this respect, they are
fundamentally different to most architectural constructions.
These consist of highly differentiated material and functional
components (e.g. steel for the structure, glass for the envelope
and different plastics for the installations, etc), which, in
themselves, are geometrically simple and can be assembled by
being added to each other to build up the desired construction.
The question arising at this point is whether the
morphological form and function principles of nature which
have developed over 3.8 billion years of evolution can be used
for structural, functional and ecologically efficient building
structures.
2.1. Paradigm shift in building construction
The use of as many equal building parts as possible, arranged
and joined in the simplest possible manner was paradigm
until a few years ago. This has dramatically changed in
the last decade through the introduction of computer-aided
manufacturing processes.
The following example may illustrate this. The American
visionary inventor Buckminster Fuller worked intensively for
over 50 years on the geometrical laws of geodesic domes (cf
Hays and Miller 2008). One of his many aims was to develop
topologies for spherical shell structures that allowed the use
of as many identical beam and node elements as possible. He
accomplished this by dividing a sphere into twenty identically
large spherical triangles (icosahedron), which were subdivided
into a regular triangular mesh. At the corner points of the large
spherical triangles, special nodes joined by only five members,
an irregularity because all the other nodes are supported by six
members (figure 2(a)).
For modern computer-aided manufacturing CAM
techniques, such considerations are obsolete; it is not
important whether the milling geometry of a joint is changed
or not; it has no influence today on the production process.
In recent years, numerous lattice shells were constructed,
consisting of many thousands of different rods and nodes,
without significant additional expense. This provides greater
freedom in the design process: Buckminster Fuller and other
designers of his time were still limited to regular geometries
such as the dome or barrel. Today’s lattice shells, however, can
adapt to almost any geometry, driven by functional or aesthetic
requirements (figure 2(b)).
During the mid-1990s such lattice shells, composed of
steel rods and glass plates, took over an important model role
3

Bioinspir. Biomim. 7 (2012) 015002 J Knippers and T Speck
(a)(b)
Figure 3. (a)ICD/ITKE Research Pavilion 2010, University of Stuttgart (photo: Roland Halbe), (b) digital fabrication of plywood strips
(photo: University of Stuttgart).
in the steel construction industry in terms of developing a
digital design and production chain. Other building techniques
including concrete and timber construction are gradually
reaching similar innovative results.
A fitting example is the research pavilion built by the
members of the Institute of Computational Design (ICD,
Professor Achim Menges) and the Institute of Building
Structures and Structural Design (ITKE, Professor Jan
Knippers) of the Faculty of Architecture and Urban Planning
at the University of Stuttgart with the help of many students
in 2010 (Menges et al 2011, Lienhard et al 2011). The
structure is entirely based on the elastic bending behaviour of
6.5 cm thick birch plywood strips. The strips were robotically
manufactured as planar elements and subsequently connected
to coupled arch systems as shown in figure 3. A radial
arrangement and interconnection of the self-equilibrating arch
system lead to the final torus-shaped design of the pavilion.
Due to the reduced structural height, the connection points
locally weaken the coupled arch system. In order to prevent
these local points from reducing the structural capacity of the
entire pavilion, the locations of the weak connection points
between the strips had to be varied along the entire length of
the structure which resulted in 80 different strip patterns being
constructed from more than 500 geometrically unique parts.
A continuous computer-aided process for design, simulation
and manufacturing was implemented to realize this structure.
Although neither the design nor the construction of
this pavilion was inspired by biological role models, it
inevitably is reminiscent of natural structures, because the
seemingly innovative principles used here are frequently found
in nature. These principles are the homogeneous nature of the
construction using a single textured material, the parametric
differentiation of the plate geometry with a uniform basic
typology and the shaping of large elastic surface deformations.
This example shows that digital simulation, planning and
production processes open up new methods of approaching
natural role models. Today, the technical requirements
for a transfer of knowledge from nature into construction
engineering are much more prevalent than those even a few
years ago (Fratzl 2007, Masselter et al 2011, Masselter
and Speck 2011,Milwichet al 2006, 2008, Pohl et al
2010). Therefore, the study of biomimetics for architects and
engineers is even more relevant today than ever before.
2.2. Natural design principles in architecture
An important characteristic of natural systems is a multi-
layered, finely tuned and differentiated combination of basic
components which lead to structures that feature multiple
networked functions (Dunlop and Fratzl 2010, Fratzl 2007,
Fratzl and Weinkammer 2007, Jeronimidis 2000a, 2000b,
Masselter and Speck 2011, Milwich 2008). Such design
principles have so far virtually never been used architecturally;
if at all, only in a very basic form (Godfaurd et al 2005). They
can be classified as follows.
• Heterogeneity: natural constructions are characterized
by a geometric differentiation of their elements. As
described above, the introduction of digital design
and manufacturing processes increases the possible
level of geometric differentiation in building structures
and facilitates the transfer of natural morphologies
into architecture. Additionally, natural structures are
characterized by local adaptations of their physical
or chemical properties. Material research is currently
concerned with gradient materials, such as the targeted
control of porosity in concrete, trying to match
the opposing properties of thermal conductivity (high
porosity) and mechanical load bearing (low porosity) to
meet local requirements. The introduction of gradient
materials in construction practice is still pending.
• Anisotropy: many natural constructions consist of fibre-
reinforced composite materials. Similarly modern high-
performance materials are increasingly based on the
principle of anisotropic fibre reinforcements. Current
developments are concerned with the manufacturing
methods for producing a demanding arrangement
of stress-related fibres, especially around load
concentrations at branching points (cf Fischer et al 2010,
4

Bioinspir. Biomim. 7 (2012) 015002 J Knippers and T Speck
Figure 4. Folding Bridge Kiel 1998. Architect: von Gerkan Marg and Partner; Engineer: Schlaich Bergermann and Partner (photo: Klaus
Frahm).
Masselter and Speck 2011). Therefore, many valid
suggestions can be expected, resulting from the study of
natural role models.
• Hierarchy: biological structures are characterized by
a multi-level hierarchical structure from nano- to
macro-scale, each level consisting of similar molecular
components, but giving rise to different and, to some
extent, independent functional properties and adaptions
(figure 1).
In contrast, building structures show a very different
understanding of hierarchy: they consist of a static
system (e.g. optimized for maximum efficiency) using
components (e.g. girders with an optimized cross section)
made of different materials (e.g. optimized for maximum
strength or processability).
The natural conception of hierarchy still remains
virtually unexplored in architecture and civil engineering
so far. Current approaches for highly loaded structures
are moving away from static systems with a few specific
structural elements, towards structures with increased
redundancy, but the advantages and possibilities offered
by implementing a multi-level hierarchical construction
as found in living beings are still not being taken into
consideration.
• Multifunctionality: botany fibres simultaneously serve
mechanical and diverse physiological functions. Current
research is focusing on integrating monofunctional
components into multifunctional material systems, such
as the integration of sensors and actuators in adaptive
composite structures for aircraft, or elements for
generation, transmission and storage of energy in facade
elements. Systems which reflect natural structures in
terms of uniform texture with a variety of functions are
unknown in architecture and engineering so far.
This classification is, of course, not complete. It could be
widely increased by describing principles such as redundancy,
adaptability, etc.
3. Case study on convertible structures
Based on selected functionality, namely the movement of
structures, it will be analysed how biomimetics can be used in
specific design questions.
Questions regarding this issue came to light during the
first author’s many years of work on kinematic structures,
such as the three-field Bascule Bridge in Kiel Horn, Germany
(figure 4), where he was employed as a project manager
responsible for design for Schlaich Bergermann and Partner.
The bridge is moved through a complex cable system of
numerous ropes, winches and rollers, and simultaneously each
change to the construction’s position had to be stabilized
to counteract wind loads from all directions (Knippers and
Schlaich 2000). The architectural intent was to incorporate not
only the mechanics but also the aesthetics of the surrounding
harbour cranes and transfer it to the bridge construction. This
bridge, however, is a unique item; it was planned and built
without any reference projects or prototypes. This is also
the case for the majority of structures in architecture. It is a
major contrast to industrial machinery and, for example, the
surrounding cranes which are usually developed with extensive
test runs and prototypes of various scales. This approach often
leads to problems in practice which can only be solved by
tedious experimentation on the finished object.
The arising question is how one can reduce the
complexity of movable building structures. This leads
almost automatically to the study of natural role models.
Botany in particular provides the most radical answer which
stands in total contradiction to the technical solution as
shown in figure 4. Many plant organs move without
any specific mechanical elements but through the locally
adapted and adaptive flexibility of their components. One
can distinguish between autonomous and non-autonomous
movements. Active autonomous movements are characterized
by motor organs, e.g. pulvini driven by a change of
turgor pressure. Passive autonomous movements occur
by changing physical circumstances, e.g. bending through
desiccation. Non-autonomous movements are mostly
reversible deformations caused by the release of stored elastic
energy following an external trigger or by direct application
of mechanical forces (Burgert et al 2007, Burgert and Fratzl
2009a, 2009b,Dawsonet al 1997, Elbaum et al 2007, 2008,
Fratzl et al 2008, Lienhard et al 2009, 2010, 2011a, 2011b,
Martone et al 2010, Melzer et al 2010, Poppinga et al
2010a, 2010b, Schleicher et al 2010, 2011, Vincent et al 2011).
If and how such plant movements can be used technically
was investigated by developing the elastic kinematics for a
facade shading system (Lienhard et al 2009, 2010, 2011a,
5

Bioinspir. Biomim. 7 (2012) 015002 J Knippers and T Speck
(b)(a)
Figure 5. Process sequences in biomimetic research. (a) Bottom-up process of biomimetics (biology push). (a) Top-down process of
biomimetic research (technology pull).
(a)(b)(c)
Figure 6. Elastic deformation of the kinetic system in the Strelitzia reginae flower. When mechanical force is applied (as indicated by an
arrow), the sheath-like perch opens (adapted from Lienhard et al 2011b).
2011b). This exemplifies a top-down process of biomimetics
(figure 5). Screening various plants identified the movements
of the ‘bird of paradise’ flower (Strelitzia reginae) as a suitable
kinematic principle. The Strelitzia’s flower features two adnate
petals that form a perch for pollinating birds. When a bird sits
on this perch to sip the nectar, its weight causes the perch to
bend down. In a simultaneous movement, the petal lamina
exposes the anthers and the style that are otherwise hidden and
kept safe (figure 6). This bending actuates a lateral unfolding
of the wings (lamina) (Poppinga et al 2010a, 2010b).
From an engineering perspective, the arrangement of
fibre-reinforced ribs, lamina and wings, which the perch
consists of, initially appears to be quite a complex design.
A gradual abstraction, described in detail in Poppinga et al
(2010a, 2010b) and Lienhard et al (2010, 2011a, 2011b),
transforms the elastic kinematics into a simple mechanism
which consists of a thin shell element attached to a beam
(figure 7).
The equilibrium path of the shell element is a non-
symmetrical bending motion, triggered by torsional buckling
which is induced by uniaxial bending of the attached
beam. This torsional buckling phenomenon is well known
to engineers. However, in structural design, it is usually
considered as a failure, which needs to be prevented through
design countermeasures and static verification. Nature,
however, exploits this principle and uses it actively to mobilize
certain functions.
Based on the first physical models and numerical
simulations, a prototype facade shading system called
Flectofin
R

was developed (figure 8) and registered for a patent
(Lienhard et al 2010, 2011a, 2011b, patent application). The
Flectofin
R

lamellas consist entirely of fibreglass-reinforced
plastic, which offers high tensile strength combined with low
bending stiffness, allowing for large elastic deformations.
Because the system functions without a straight turning
axis but with a bent backbone, it can also be adapted to
facades with curved geometries. This represents a significant
expansion of possible future applications. Another important
advantage is the shading system not having any maintenance-
intensive parts such as sliding joints or hinges. This reduces
costs for maintenance and care. Presumably, this mode of
6

Bioinspir. Biomim. 7 (2012) 015002 J Knippers and T Speck
(a)(b)
Figure 7. Simple physical model as a first-level abstraction of the kinematic system in the Strelitzia flower (adapted from Poppinga et al
2010b). Courtesy of WIT Press from the book C A Brebbia (ed) 2010 Design and Nature V pp 403–10.
Figure 8. Prototype of the fa¸cade shading system based on the Flectofin
R

produced in collaboration with the industrial partner Clauss
Markisen (adapted from Lienhard et al 2011b).
function will also increase the durability of the biomimetic
facade shading system.
3.1. Biomimetics in the architectural design process—design
of the thematic Pavilion EXPO 2012
The opportunity of introducing such systems on a larger scale
in an architectural design will be presented at the Thematic
Pavilion at EXPO 2012 in Yeosu, Korea (figure 9). A
kinematic media facade with 108 individually controllable fins
is planned on the pavilion side facing the expo. The design
is the result of an open design competition which was won
by Soma architects (Vienna, Austria). The technical concept
of the kinematic fins comes from Knippers Helbig Advanced
Engineering, Stuttgart, New York. The facade can adapt to
light conditions and physical building conditions and allows
the artistic staging of special lighting effects. It has a total
length of 140 m and a height of between 3 and 14 m, and is
designed to withstand the very high wind speeds on the Korean
coast.
It was initially attempted to scale Flectofin
R

to the size of
this fa¸cade. However, this proved to be difficult in its original
configuration. On the one hand, it did not fulfil all aspects of
the architectural design; on the other hand, without additional
structural reinforcement, it does not offer enough stability to
withstand the high wind loads. Inspired by the research on
plant movements, another kinetic system has been developed
(figure 10). The facade is made of slightly curved plates which
are supported by two hinged corners at the top and the bottom.
In the other two corners, a small compressive force is applied
in the plane of the fin, which leads to a controlled buckling.
This principle shows locally smaller strains than the Flectofin
R

7

Bioinspir. Biomim. 7 (2012) 015002 J Knippers and T Speck
Figure 9. Thematic Pavilion EXPO 2012, Yeosu, Korea; architect: Soma architects, Vienna; Engineer kinetic fa¸cade: Knippers Helbig;
Stuttgart, New York (visualisation: Soma
/isochrome).
Figure 10. Kinematic principle of the Yeosu fa¸cade (photo: Knippers Helbig).
but does not open completely. It perfectly matches the initial
design intentions of the architects and offers a favourable ratio
of structural stability and actuation energy (figure 9).
The elastically deformable fins are made of fibreglass-
reinforced plastic. They are up to 14 m high, 1.25 m wide and
only 9 mm thick with an additional stiffener on the side with
less-elastic deformation (the right edge in figure 10). When
open, the curved geometry, together with the residual stress
state, results in a very rigid system that deforms only a few
millimetres under high wind loads. In its closed state, the
adjacent plates are clamped together so that the facade can
withstand even the strongest storms without damage.
4. Conclusion
Both the Yeosu shading system and the Flectofin
R

movements
are made possible via elastic deformations that are associated
with correspondingly large strains. Both cases show nonlinear
deformation which, from a structural engineer’s perspective,
is considered to be a stability failure, and usually needs to
be prevented by sophisticated nonlinear analysis and bracings
or reinforcement. Even though the principle of the Yeosu
facade does not follow the abstraction of a plant movement
directly, the underlying idea was inspired and derived from
the observation and analysis of natural role models.
This encouraged the search for solutions outside the
traditional methods of design and construction and going
beyond preconceptions, such as avoiding disproportionately
growing deformations and stability failure modes.
The two examples show that a linear understanding of
biomimetics, as illustrated in figure 5, may only be sufficient
if the focus is on the abstraction of single functions as found in
technical products such as the shading system Flectofin
R

.In
architectural tasks, such as the design of the facade in Yeosu,
however, differing requirements between the aesthetics and
functionality have to be met in a given set of defined boundary
conditions. In addition, the biological role models very often
have to be scaled up to a large size, which leads to increasingly
difficult functional requirements.
In the context of architecture or building structures, a
linear abstraction process is therefore difficult to maintain.
Instead, an expanded definition of biomimetics is required:
the analysis of natural form and function principles have
the potential to stimulate architects and engineers to
8

Bioinspir. Biomim. 7 (2012) 015002 J Knippers and T Speck
fundamentally new strategies in architectural design and
technical implementation.
Acknowledgments
The work presented in this paper is supported by the funding
directive BIONA by the German Federal Ministry of Education
and Research. The authors were consulted by the Competence
Network Biomimetics. We want to thank Dipl.-Ing. Julian
Lienhard, Dipl.-Biol. Simon Poppinga, Dr Tom Masselter and
Simon Schleicher M.Arch. for the successful collaboration on
elastic architecture within the funding directive BIONA.
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