- Fibres are the basic building blocks of biology and are successful due to how they are organized, not just the materials themselves. The key fibres are cellulose, collagen, chitin, and spider silk. - Thigmo-morphogenesis refers to how organisms change shape in response to their environment through slow adaptations, which occurs due to the fibrous nature of biological materials. - Mechanoreceptors in all organisms amplify mechanical strains from the environment as electrical signals, which then trigger responses through material organization in lower organisms or neural processing in higher organisms.

1. Biomimetics
Fibre organisation strategies in nature
Biology makes use of remarkably few materials and
nearly all loads are carried by fibrous composites.
There are only four types of fibers: cellulose in plants,
collagen in animals, chitin in insects and crustaceans
and silks in spider webs. These are the basic materi-
als of biology and they have much lower densities
than most engineering materials. They are success-
ful not so much of what they are but because the
way in which they are put together.
Thigmo-Morphogenesis
Thigmo-morphogenesis, refers to the changes in
shape, structure and material properties that are pro-
duced in response to transient changes in environ-
mental conditions. This property can be observed
in the movement of sunflowers, bone structure and
sea urchins.These are all growth movements or slow
adaptations to changes in specific conditions that
occur due to the nature of the material, which are
essentially fibrous tissue.
Morpho-Mechanical Computation
One of the most interesting aspects of mul-
tifunctionality and integration in biology is
the way in which receptors detect and am-
plify mechanical strains and displacements
through mechano-receptors. They do exist
in all creatures, plants and animals. These
receptors function as mechanical signal am-
plifiers of strain concentrations caused by
changes in the environment.
The energy input or stimulus from the en-
vironment is picked up by the mechanore-
ceptors which transduce them into electric
signals. The electrical signals acts as the ba-
sic information which is further processed
by the nervous system in case of higher lev-
el organisms while in lower level organisms,
the signals are used for sequential actua-
tion through altering the material organiza-
tion. The responsive behaviour or adaptive
growth in natural organisms emerge as a re-
sultant of a complex process of sensing, in-
formation processing, control and actuation.
Energy Input
(Stimulus)
Device
(Transduction)
Electrical
Signal
Filtering
Processing
Response
Behaviour
Actuator
Systems
Controlled
Structures
Smart
Structures
Smart
Adaptive
Structures
Intelligent
Adaptive
Structures
Self-
learning
Reactive
Structures
Self-
learning
Smart
Structures
Structures
Neural Network Systems
Sensor
Systems
Fibre Organisation Strategies
Morpho-Mechanical Computation
Thigmo-Morphogenesis
Precedents
s ense
a ctuate
e nergy
c ontrol
s a
ec
s a
e
s a
e
c
Hypo-surface
Cartesian- Wax
Smart Plane
s a
e
c
s a
e
Responsive Systems in Nature
Lower-level Organisms
Higher-level Organisms
Biomimetics Research
MSc Dissertation
Maria Mingallon, Konstantinos Karatzas, Sakthivel Ramaswamy
Emergent Technologies and Design Programme 2008-09

2. Base Material_Fibre Composite
In its most basic form a composite material is one
which is composed of at least two elements working
together to produce material properties that are
different to the properties of those elements on their
own
The greatest advantage of composite materials is
strength and stiffness combined with lightness.
By choosing an appropriate combination of
reinforcement and matrix material, we produce
properties that exactly fit the requirements of a
particular structure or purpose.
Another advantage of composite materials is that
they provide design flexibility -They can be moulded
into complex shapes.
Sensing
Fibre Optics
An optical fibre is a glass or plastic fibre that
carries light along its length. Light is kept in the
core of the optical fibre by total internal reflection.
Widely used in fibre-optic communications, which
permits transmission over longer distances and at
higher bandwidths (data rates) than other forms of
communications
Fibre Optic Sensors
Canmeasurestrain,temperature,pressure,viscosity,
water vapour content, and other by modifying a
fibre so that the quantity to be measured modulates
the intensity, phase, polarization, wavelength or
transit time of light in the fibre.
Thermocouples
A thermocouple is a junction between two
different metals that produces a voltage related to a
temperature difference.
Widely used type of temperature sensor
Strain Gauges
A device used to measure the strain of an object.
Thegaugeisattachedtotheobjectandastheobject
is deformed, the foil deforms, causing its electrical
resistance to change. This resistance change is
related to the strain by the quantity known as the
gauge factor.
Actuation
A shape memory alloy (SMA) is an alloy that
“remembers” its shape, and can be returned to that
shape after being deformed, by applying heat. SMAs
have the highest known force/weight ratio among
actuators
Shape Setting
TheNi-Tiribbonandwiresweretrainedbyrolling
them around metal pipes and maintaining
them in position while they were placed in an
oven. The oven was heated upto 500°C and
the temperature was maintained for 5 minutes.
The SMAs were subsequently removed from the
oven and immediately immersed in cold water
whilst maintaining the imposed bend shape
throughout the cooling procedure.
Actuation Experiments - Weight lifting
These set of experiments were focused on
extrapolating the Force to Weight ratio and
Force-Time graph. It was observed that the SMA
ribbon of 9 gm in a cantilevered position could
lift load up to 114 gm.The load carrying capacity
of the SMA ribbon improved significantly when
the strip was simply supported. The ribbon of 9
gm could lift a load of 883 gm, almost 100 times
it self-weight.
Actuated Canopy
A smart fibre composite, with embedded SMAs
could allow the strip morphology of the canopy
todynamicallyreorganise,openandclosebased
on current environmental conditions.
Actuated Openings
The SMA wires were cut and bundled together
forming arcs. A bundle of three fibres was
woven to the felt to create openings. As they
were heated the surface opens of both on the
inside and outside.
Actuation + Control Experiments
In the second Phase of our actuation
experiments, we added the factor of control in
the actuation process. The temperature of the
SMA ribbons was monitored, and the system
actuated accordingly.
Sensing Experiments
Strain Gauges were used to sense the strain, on
a piece of fibre-reinforced polyester resin. The
strain gauges processing unit was calibrated
accordingly and the sensing system was
prepared to be linked with the actuation system
and integrated in the final model.
Sensing + Actuation + Control
Thefinalmodel(below)isaGlassFibreReinforced
EpoxyResinSandwichStructurewithembedded
SMAs (4 Ribbons) and Thermocouples. Two
Strain Gauges are attached on the surface.
When the Strain Gauges sense strain, the give a
signal to their processing unit. Sequentially, an
output of 0-2Volts is generated and acts as an
input for another controller that switches on or
off the actuation circuit.
40 degrees
30 degrees
53 degrees
65 degrees
Technology + Experiments
MSc Dissertation
Maria Mingallon, Konstantinos Karatzas, Sakthivel Ramaswamy
Emergent Technologies and Design Programme 2008-09

3. Geometry
In structural design, traditional methods tend to
group structural elements in accordance with the
type of external loads they would have to withstand
during their life time.
Our aim has been to develop a material system ca-
pable of withstanding a wide spectrum of loading
conditions by adapting its structural capacity when
and where required. This adaptation occurs via both
the global and local geometry.
Stiffness differentation in the global geometry is
achieved through the manipulation of two factors:
overall form derived through digital form finding
and fibre organisation based on the analysis of prin-
cipal stresses.
Fuzzy Logic
Multi-valued logic derived from
fuzzy set theory to deal with rea-
soning that is approximate rather
than precise.
Actuation Logic
Actuator positioned along su-
ture curve’ enhances the system
through dynamic adaptation.
Space Truss from Interwoven Continuous Surface
Topology
Local Geometry
Global Geometry Global Geometry
Screen Walls by Erwin Hauer; Installation in showroom of Knoll Internacional de Mexico, Mexico City
0
1
Two Hexagonal Grids
Layers Connectivity - Tripods
Tripods frame Suture Curves
Material Hierarchies
Concept
Space Truss
Space Truss
Openning Suture Curves
Grids Distorsion
Grids Spacing
Variables Curvature
Height
a
h
Continuous Surface
Space Truss
Fibre Distribution
Shape Memory Alloy
Actuation
Sensing
Material
Fibre Optic
Structural Fibres
a a’
s
m
a
m s a
e
a a’
Geometry_01
MSc Dissertation
Maria Mingallon, Konstantinos Karatzas, Sakthivel Ramaswamy
Emergent Technologies and Design Programme 2008-09