Building Smaller Machines

How might we design and build smaller machines? First, we observe nature and abstract away from nature our ideas of what we want to build. Were we to copy a bee, we must "transliterate"

from the biological bee blueprint language into a machine language of our own. Think of what a bee does. Whether the hemo-coel contains much hemolymph or merely moistened surfaces, connectivity within the hemocoel suffices for particles to move from place to place without obstruction. Flows and transport differ in large and small hemocoels.

We begin with generalizations: our common abstract notions of size, weight and scaling. Objects seem lighter in proportion to their size as we scale them down. When descending much below bee size, however, physics changes markedly. Something thrown, flicked or kicked instead of landing close to its actuator now usually ends up far away. Compare our jumping flea's ability to jump more than twelve body heights with our Olympic records for the high jump.

Or look at gold. Nanoparticles, having widths of a few nanometers to a few hundred, contain tens to thousands of atoms and live and have their being within the realm of meso-physics. At intermediate sizes, nanoparticles straddle quantum and Newtonian realms: realms where common elements often display novel properties. Of two nanoparticles of gold, for example, the slightly larger particle may melt at a different temperature and possess a different conductivity and be a different color than the smaller one. So at the meso-level of organization, instead of changing the components and composition of our materials, we might consider altering size (Ref: Size Relationships).

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