Biomimetics: Reality, Challenges, and Outlook - Biomimetics: Biologically Inspired Technologies - page 498

tute proteins in order to make products and services that meet the needs of humans and the demand
of consumers. Cloning the DNA allows you to produce synthetic life while adapting nature's
principles allows you to create artificial life and biomimetic tools and capabilities.

20.3 CHARACTERISTICS OF BIOLOGICALLY INSPIRED MECHANISMS

There are many characteristics that identify a biomimetic mechanism and some of the important
ones include the ability to operate autonomously in complex environments, perform multifunc-
tional tasks and adaptability to unplanned and unpredictable changes. Making mechanisms with
such characteristics dramatically increases the possible capabilities and can reach levels that can be
as good or superior to humans or animals. This may include operating for 24 h a day without a break
or operating in conditions that pose health risks to humans. Benefits from such capabilities can
include performance of security monitoring and surveillance, search and rescue operations, chem-
ical, biological, and nuclear hazardous operations, immediate corrective and warning actions as
well as others that are only limited by our imagination. Some of the biologically inspired capabil-
ities that are/can be implemented into effective mechanisms include:

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Multifunctional materials and structures (Chapters 12 and 14): Biological systems use
materials and structures in an effective configuration and functionality incorporating sensor and
actuation to operate and react as needed. Using multifunctional materials and structures allows
nature to maximize the use of the available resources at minimum mass (Rao, 2003). An example is
our bones, which support our body weight and provide the necessary body stiffness while operating
as our ''factory'' for blood that is produced in the bone marrow. Another example is the feathers in
birds, which are used for flying as well as for thermal insulation and the control of heat dissipation.
Mimicking multi-functionality capabilities, system are made to operate more effectively in robots
provided with ability to grasp and manipulate objects and with mobility of appendages or sub-
appendages (hands, fingers, claws, wings). Some of the concerns with regard to the application of
multiple functionality is the associated design difficulties where there is a need to simultaneously
satisfy many constraints. Design changes in one part of the system affect many other parts.

High strength configurations: The geometry of birds' eggs have quite interesting character-
istics. On the one hand, they are amazingly strong from the outside, so a bird can warm its eggs by
sitting on them till the chicks hatch. On the other hand, they are easily breakable from the inside, so
the chicks can break the shell with their beak once they are ready to emerge into the outside world.

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Just-in-time manufacturing: Producing as needed and at the time of the need is widely used in
biology and such examples include the making of the web by spiders or the production of the toxic
chemicals by snakes. Such a capability is increasingly adapted by industry as a method of lowering
the cost of operation. Many industries are now manufacturing their products in small quantities as
needed to meet consumers demand right at the assembly line. Thus, industry is able to cope with the
changing demand and decline or rise in orders for its products.

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Deployable structures: The leaves of most plants are folded or rolled while still inside the bud.
The way they unfold to emerge into to a fully open leaf can inspire deployable structures for space,
including gossamer structures such as solar sails and antennae as well as terrestrial applications
such as tents and other covering structures (Guest and Pellegrino, 1994; Unda et al., 1994;
Kobayashi et al., 1998).

Hammering without vibration back-propagation: The woodpecker (Picidae family) has the
amazing capability to tap and drill holes in solid wood in search of insects and other prey (Bock,
1999). One example is the Northern Flicker ( Colaptes auratus ), which is a member of the
woodpecker family, shown in Figure 20.1. The brain of the woodpecker is protected from damage
as there is very little space between it and the skull preventing rotation during impact. Some
woodpecker species have modified joints between certain bones in the skull and upper jaw, as well
as muscles which contract to absorb the shock of the hammering. A strong neck, tail-feather
muscles, and a chisel-like bill are other hammering adaptations in some species. This ability to
absorb the shocks and prevent damage to the bird brain or cause disorientation could inspire a

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