Guest Writer - Gastautor - Gast Schrijver

Science and Technology:
The Power of Molecular Manufacturing

 

So what's the big deal about molecular manufacturing? We have lots of kinds of nanotechnology. Biology already makes things at the molecular level. And won't it be really hard to get machines to work in all the weirdness of nanoscale physics?

The power of molecular manufacturing is not obvious at first. This article explains why it's so powerful--and why this power is often overlooked. There are at least three reasons. The first has to do with programmability and complexity. The second involves self-contained manufacturing. And the third involves nanoscale physics, including chemistry.

It seems intuitively obvious that a manufacturing system can't make something more complex than itself. And even to make something equally complex would be very difficult. But there are two ways to add complexity to a system. The first is to build it in: to include lots of levers, cams, tracks, or other shapes that will make the system behave in complicated ways. The second way to add complexity is to add a computer. The computer's processor can be fairly simple, and the memory
is extremely simple--just an array of numbers. But software copied into the computer can be extremely complex.

If molecular manufacturing is viewed as a way of building complex mechanical systems, it's easy to miss the point. Molecular manufacturing is programmable. In early stages, it will be controlled by an external computer. In later stages, it will be able to build nanoscale computers. This means that the products of molecular
manufacturing can be extremely complex--more complex than the mechanics
of the manufacturing system. The product design will be limited only by
software.

Chemists can build extremely complex molecules, with thousands of atoms
carefully arranged. It's hard to see the point of building even more complexity. But the difference between today's chemistry and programmable mechanochemistry is like the difference between a pocket calculator and a computer. They can both do math, and an accountant may be happy with the calculator. But the computer can also play movies, print documents, and run a Web browser. Programmability adds more potential than anyone can easily imagine--we're still inventing new things to do with our computers.

The true value of a self-contained manufacturing system is not obvious at first glance. One objection that's raised to molecular manufacturing is, “Start developing it--if the idea is any good, it will generate valuable spinoffs.” The trouble with this is that 99% of the value may be generated in the last 1% of the work.

Today, high-tech intricate products like computer chips may cost 10,000 or even 100,000 times as much as their raw materials. We can expect the first nanotech manufacturing systems to contain some very high-cost components. That cost will be passed on to the products. If a system can make some of its own parts, then it may decrease the cost somewhat. If it can make 99% of its own parts (but 1% is expensive), and 99% of its work is automated (but 1% is skilled human labor), then the cost of the system--and its products--may be decreased by 99%. But that still
leaves a factor of 100 or even 1,000 between the product cost and the raw materials cost.

If a manufacturing system can make 100% of its parts, and build products with 100% automation, then the cost of duplicate factories drops precipitously. The cost of building the first factory can be spread over all the duplicates. A nanofactory, packing lots of functionality into a self-contained box, will not cost much to maintain. There's no reason (aside from profit-taking and regulation) why the cost of the factory shouldn't drop almost as low as the cost of raw materials. At that point, the cost of the factory would add almost nothing to the cost of its products. So in the advance from 99% to 100% self-contained manufacturing, the product cost could drop by two or three orders of magnitude. This would open up new applications for the factory, further increasing its value.

This all implies that a ten billion dollar development program might produce a trillion dollars of value--but might not produce even a billion dollars worth of spinoffs until the last few months. All the value is delivered at the end of the program, which makes it hard to fund under American business models.

A factory that's 100% automated and makes 100% of all its own parts is hard to imagine. People familiar with today's metal parts and machines know that they wear out and require maintenance, and it's hard to put them together in the first place. But as nanoscientists keep reminding us, the nanoscale is different. Molecular parts have squishy surfaces, and can bend without breaking or even permanently deforming. This requires extra engineering to make stiff systems, but diamond (among other possibilities) is stiff enough to do the job. The squishiness
helps when it's time to fit parts together: robotic assembly requires less precision. Bearing surfaces can be built into the parts, and run dry. And because molecular parts (unlike metals) can have every atom bonded strongly in its place, they won't flake apart under normal loads like metal machinery does.

Instead of being approximately correct, a molecular part will be either perfect--having the correct chemical specification--or broken. Instead of wearing steadily away, machines will break randomly--but very rarely. Simple redundant design can keep a system working long after a significant fraction of its components have failed, since any machine that's actually broken will not be worn at all. Paradoxically, because the components break suddenly, the system as a whole can degrade gracefully, while not requiring maintenance. It should not be difficult
to design a nanofactory capable of manufacturing thousands of times its own mass before it breaks.

To achieve this level of precision, it's necessary to start with perfectly identical parts. Such parts do not exist in today's manufacturing universe. But atoms are, for most purposes, perfectly identical. Building with individual atoms and molecules will produce molecular parts as precise as their component atoms. This is a natural
fit for the other two advantages described above—programmability, and self-contained automated manufacturing. Molecular manufacturing will exploit these advantages to produce a massive, unprecedented, almost incalculable improvement over other forms of manufacturing.



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Chris has studied nanotechnology and molecular manufacturing for more than a decade. After successful careers in software engineering and dyslexia correction, Chris co-founded the Center for Responsible Nanotechnology in 2002, where he is Director of Research. Chris holds an MS in Computer Science from Stanford University.

Copyright © 2004 Chris Phoenix

 

Chris Phoenix

CRN Director of Research