Transcript Document

LEARNING FROM NATURE,
WORKING WITh
NATURE.
“We are all too much
inclined to walk through
life with our eyes shut. There
are things all around us,
and right at our very feet,
that we have never seen;
because we have never
really looked
.”
Alexander Graham Bell
Many inventors, have borrowed
ideas and inspiration from
nature.
Our natural world offers a
magical place for contemplation
and daydreaming, an umlimited
wellspring of ideas that triggers
the creative impulses of inventors
both historic and contemporary.
Inventors display distinctive habits
of mind – curiosity, persistence,
imagination, communication
and problem-solving.
NATURE
Vs
Man-made designs
General features
Exact Duplicates
- Fault tolerance
- Standardisation
- Self-repair
- Non self-renewable
- Highly adaptable
- Operates within
specifications
Commercial products are duplicated as closely as
possible to assure quality and performance
Biological designs provide
for identity and
performance
• Mechanisms
• Structures and Tools
• Processes
• Shapes
• Material/Composites
Nature’s Paradigms
Biologically Inspired Mechanisms
Pumping mechanisms
Linear motors driven by
piezoelectric actuators –
Geometrid caterpillar or
inchworm
• Peristaltic pumps – digestive system
• Tidal pumping – lungs
• Pumping via valves and chambers - heart
Controlled Adhesion
Renown for their ability to walk up walls or
hang from the ceiling on one toe, the
colourful lizards of the Gecko family, owe
their prowess to their remarkable foot pads.
Understanding their adhesion mechanism opens the door
to manufacturing the first biologically inspired dry,
adhesive microstructures that can have wide-spread
application.
Bio-inspired
Adhesives
One square centimeter of gecko
tape can support a weight of 1kg
Passive Cooling for Buildings
Termite mounds are marvellously
engineered for passive internal
temperature consistency
Biologically – inspired
Structures and Tools
Natural compound eyes combine small
eye volumes with a large field of vision
and inspires alternative imaging
principles for development of new microoptics technology.
Repeating microstructures on peacock
feathers inspires improvements for
screens on laptops and digital cameras.
Velcro was invented by George de
Mestral who obtained his inspiration
while trying to remove annoying burrs
from his clothes and dog’s fur.
Inspiration has also been drawn from
swimming creatures that have legs with
gossamer.
The design features of Japan’s Shinkansen-500 series
bullet train was modeled on the owl plummage to
reduce air resistance noise and the air piercing nose
cone was inspired by the kingfisher’s beak.
The hydrophobic surface structure of the
lotus leaf became the inspiration for a
new kind of self-cleaning paint.
Lessons from the Honeycomb Structure
Principle of tessellation - the method
of repeating patterns so that there is
no overlap and no gaps.
The honeycomb structure has inspired the
design of a soft wall partition that can open and
curve in a variety of ways or fold away when not
in use. The honeycomb structure, with its
vertical cells of air, and the crenelated surface
of soft wall also make the most of the wall's
acoustic dampening properties. Sir Paul
McCartney purchased these softwalls for his
recording studio.
The honeycomb pattern used in beehives was also the
basis for the Honeycomb System of Housing. The
creative power of tessellation is not merely decorative
but representative of functional space.
Lessons taken from the school of
hard knocks
WOODPECKER
Cranial structure and surrounding tissues provides
inspiration for design of shock absorbers
Feathers surrounding its nostrils inspire the design of
better dust masks.
Bio-inspired Materials
A layer of barnacle cement three ten thousandths of an
inch thick over one square inch will support a weight of
7000 pounds. It is even stronger than epoxy cement. At
temperatures above 6000°F the glue will soften but not
melt, and at 380°F the cement will not crack. It does not
dissolve in most strong acids, alkalis, organic solvents,
or water. If man could learn to manufacture this cement,
which barnacles have been using for millions of years, it
could be used to mend broken bones and hold fillings in
teeth.
Screen, mesh and sieving – that allow
separation of objects of various sizes may
be attributed to the evolution on the net.
Fishing nets and screens –
inspiration from the spider web
Spider Structures and Tools
The following slides show
spider silk fibres taken at
various magnifications
using a scanning electron
microscope
Spider
silks and their uses
Silk
Uses
Major ampullate dragline
Web frame and radii
Minor ampullate
Web reinforcement
Flagelliform
Core fibres of adhesive spiral
Aggregate
Adhesive silk of spiral
Cylindrical
Cocoon
Aciniform
Swathing and inner egg sack
Pyriform
Attachment disk and joining fibres
Highly oriented alanine-rich
crystals of beta–sheets (rectangles)
Amorphous glycinerich matrix composed
of about 70% percent
fiber (curved lines)
Weakly oriented yet crystalline
unaggregated sheets (canted
sheet-like structures)
Diagram of the proposed model for the
molecular arrangement of alanine
residues in a fiber of spider dragline silk.
(From A.H. Simmons, C.A. Michal, and
L.W. Jelinski, Science 271:84—87 (1996)
Comparisons of mechanical
properties of spider silk
Material
Strength
(N m-2)
Elasticity
(% )
Energy to
break (J kg-1)
Dragline silk
(major ampullate)
4 x 10 9
35
1 x 105
Flagelliform silk
1 x 109
>200
1 x 105
Minor ampullate
1 x 109
5
3 x 104
Kevlar
4 x 109
5
3 x 104
Rubber
1 x 106
600
8 x 104
Tendon
1 x 109
5
5 x 103
Nylon, type 6
7 x 107
200
6 x 10
4
BOB – Our Lab Spider
While most spiders have multiple pairs of eyes,
vision is a secondary sense in the vast majority of
species. Most spiders primarily interact with the
world through tactile sensation. They are covered
in highly sensitive hairs that pick up even low-level
vibrations in whatever the spider is standing on
(the ground, floor, leaf or web, for example). Many
spiders have additional hairs, called
trichobothria, which pick up vibrations in the air
(sound). Most spiders also have a sense of taste
and smell, which play a role in feeding and
reproduction.
One of Bob’s
hairy legs
Question: Why is it that a spider never gets
caught in its own web?
The tip of Bob’s leg
comprises serrated
walking claws, hairs
and slender spines.
Nature’s
Unsurpassed
Superiority
Lessons in sustainability
“The truth is, natural organisms have managed to do
everything we want to do without guzzling fossil fuels,
polluting the planet or mortgaging the future.” - Benyus
Acknowledgement
This presentation has been made possible through the
enthusiastic efforts and support of staff and students of the
Technology Centre for Life Sciences, Singapore Polytechnic.
Staff
Students
Dr. Puah Chum Mok
Jone Efendy
Dr. Liew Oi Wah
Chua Yi Wei
Dr. Chen Gang
Lim Wei Zheng
Dr. Zuo Zhili
Wong Yiwen
Jenny Chong Pek Ching
Puah Libby
Sunny Liew
Chng Yhee Ching
Lee Siew Hui
Radiance Lim
Thank you