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7 Future Developments

often combine multiple sensing elements with a transducer and an analysis element

(generally a form of pattern recognition). The specificity of binding/sensing is currently

still the biggest problem that must be overcome.

Hearing on the molecular scale is actually rather complicated: Vibrations in air are

converted into mechanical vibrations in a membrane via various steps and membranes

and eventually are transduced into electricity via the bending of fiber that mechani-

cally opens an ion channel. The advantages of this complicated set-up can be seen in the

human ear’s excellent sensitivity, since wavelengths are detected separately and only

recombined during the analysis-step in the brain. Since this system is so complicated,

there has not been much research into using these membranes or sensors in nanotech-

nology, but so far largely only investigations into the system itself. On the technology side

of things, microphones and receivers are commonplace on any scale. However, none

of these has so far achieved the efficiency of the basilar membrane. Acoustic sensors,

though, are starting to be used in different applications, such as sensing flow.

Skin is the largest and most complex human organ with the widest variety of func-

tions. The temperature or pressure sensors are specialized neurons and contain 3D in-

formation. Additionally, these sensors are also part of chemical and pain sensing. These

sensors are built into a complex structure that self-heals and maintains homeostasis.

Some of these functions have been mimicked in materials, but only one function at a

time has been successfully reproduced. Layered sensor films are starting to integrate

sensors on a larger scale.

In humans, all of the senses are combined into one structure, our bodies. All of the

sensor elements are analyzed by the same entity, the brain. Analysis here does not only

imply the recognition of a specific shape such as a rose, but it also implies the creation of

a connection between the rose and the feeling of love, also using memory in the process.

Robots are the technological answer to such a complex system and they use quite a few

senses. However, no robot has yet used senses that are as equally fine-tuned as the hu-

man senses on the molecular scale in combination with rational thought and complex

action based on that thought.