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224 Biomimetics: Biologically Inspired Technologies

7.4.5.3 Generating Stable Alignment and Internal Gradients

Selection of the appropriate intrinsic materials for our system implies that we need to also select the
appropriate internal gradient functions and the alignment generated by these intrinsic materials. We
need to calculate the most stable configuration for our system at no external gradient level and then
fine tune our alignment as it is applied. Application of these external gradients could generate a
situation where no stable configuration is possible within our operating conditions. This calls for
adding some further intrinsic materials to the system, which would help us to get to the stable
configuration (closure engineering) (Freitas and Merkle, 2004). This variation of the intrinsic
gradient in this manner is termed as intrinsic variational gradients to distinguish it from the
inherent intrinsic gradients generated due to the intrinsic materials.
The parameters mentioned above create the foundation for the development of mathematics for
this field. To create any system with self-replicating mechanism we need to first find out its most
stable state, then we need to calculate its behavior in the extrinsic gradients and then we need to excite
it with energy and supply of intrinsic materials so that it replicates. Though these methodologies are
not verified, further research in this area is being carried on by the authors and their collaborators.

7.5 CONCLUSIONS

Biomimetics and its principles would greatly influence the field of nanorobotics and nanotechnol-
ogy. The way nature is designed and the way nature solves its problems is of great interest to us
because they allow us to understand basic principles that would pave the way to practical
nanotechnology.
The recent explosion of research in nanotechnology, combined with important discoveries in
molecular biology, has created a new interest in bio-nanorobotic systems. The preliminary goal
in this field is to use various biological elements — whose function at the cellular level results
in a motion, force or signal — as nanorobotic components that perform the same function in response
to the same stimuli — but in an artificial setting. This way proteins and DNA could act as motors,
mechanical joints, transmission elements, or sensors. Assembled together, these components would
form nanorobots with multiple degrees of freedom, with the ability to apply forces and manipulate
objects at the nano-scale, and transfer information from the nano- to the macro-scale world.
The first research area is in determining the structure, behavior, and properties of basic bio-nano
components such as proteins. Specific problems include the precise mechanisms involved in
molecular motors like ATP Synthase, and of protein folding. The next step is combining these
components into complex assemblies. Next concepts in control and communication in swarms need
to be worked out. Again, we plan to follow nature’s path, mimicking the various colonies of insects
and animals, and transforming principles learned to our domain. Since it would require specialized
colonies of nanorobots to accomplish particular tasks, the concepts of cooperative behavior and
distributed intelligence need to be developed, possibly by using known hierarchical and other
techniques.
Principles like self-replication are the ones of greatest importance for the field of nanorobotics.
It is this life mimetics which will enable us to design and fabricate the future nanorobots having
immense capabilities and potential. These would require innovative materials (intrinsic materials)
and fabrication methodologies, with due regard to well-known manufacturing- and applications-
related safety concerns. The safety issue is of paramount importance in this field for researchers and
scientists. The proposed bio-nanorobots would be completely controlled molecular devices and are
far from being dangerous to society. Though these devices would have many unique capabilities,
which are not seen currently, they are harmful as projected in science fiction movies and books.
There is an increasing need for educating the community about the exact nature of this research and
its essential differences with the projections of the science fiction community.