Molecular manufacturing (MM) will be able to build a wide
variety of products -- but only if their designs can be specified.
[Recent science essays] have explained some reasons why nanofactory
products may be relatively easy to design in cases where
we know what we want, and only need to enter the design into
a CAD program. Extremely dense functionality, strong materials,
integrated computers and sensors, and inexpensive full-product
rapid prototyping will combine to make product design easier.
http://www.crnano.org/essays05.htm
However, there are several reasons why the design of certain
products may be quite difficult. Requirements for backward
compatibility, advanced requirements, complex or poorly understood
environments, regulations, and lack of imagination are only
a few of the reasons why a broad range of nanofactory products
will be difficult to get right. Some applications will be
a lot easier than others.
Products are manufactured for many purposes, including transportation,
recreation, communication, medical care, basic needs, military
support, and environmental monitoring, among others. This
essay will consider a few products in each of these categories,
in order to convey a sense of the extent to which the initial
MM revolution, though still profound, may be limited by practical
design problems.
Transportation is simple in concept: merely move objects
or people from one place to another place. Efficient and
effective transportation is quite a bit more difficult. Any
new transportation system needs to be safe, efficient, rapid,
and compatible with a wide range of existing systems. If
it travels on roads, it will need to comply with a massive
pile of regulations. If it uses installed pathways (future
versions of train tracks), space will have to be set aside
for right-of-ways. If it flies, it will have to be extremely
safe to reassure those using it and avoid protest from those
underneath.
Despite these problems, MM could produce fairly rapid improvements
in transportation. There would be nothing necessarily difficult
about designing a nanofactory-built automobile that exceeded
all existing standards. It would be very cheap to build,
and fairly efficient to operate -- although air resistance
would still require a lot of fuel.
Existing airplanes also could be replaced by nanofactory-built
versions, once they were demonstrated to be safe. In both
cases, a great deal of weight could be saved, because the
motors would be many orders of magnitude smaller and lighter,
and the materials would be perhaps 100 times as strong. Low-friction
skins and other advances would follow shortly.
Molecular manufacturing could revolutionize access to space.
Today's rockets can barely get there; they spend a lot of
energy just getting through the atmosphere, and are not as
efficient as they could be. The most efficient rocket nozzle
varies as atmospheric pressure decreases, but no one has
built a variable-nozzle rocket. Far more efficient, of course,
would be to use an airplane to climb above most of the atmosphere,
as Burt Rutan did to win the X Prize. But this has never
been an option for large rockets. Another problem is that
the cost of building rockets is astronomical: they are basically
hand-built, and they must use advanced technology to minimize
weight. This has caused rocketry to advance very slowly.
A single test of a new propulsion concept may cost hundreds
of millions of dollars.
When it becomes possible to build rockets with automated
factories and materials ten times as strong and light as
today's, rockets will become cheap enough to test by the
dozen. Early advances could include disposable airplane components
to reduce fuel requirements; far less weight required to
keep a human alive in space; and far better instrumentation
on test flights -- instrumentation built into the material
itself -- making it easier and faster to determine the cause
of failures. It seems likely that the cost of owning and
operating a small orbital rocket might be no more than the
cost of owning a light airplane today. Getting into space
easily, cheaply, and efficiently will allow rapid development
of new technologies like high-powered ion drives and solar
sails. However, all this will rely on fairly advanced engineering
-- not only for the advanced propulsion concepts, but also
simply for the ability to move through the atmosphere quickly
without burning up.
Recreation is typically an early beneficiary of inventiveness
and new technology. Because many sports involve humans interacting
directly with simple objects, advances in materials can lead
to rapid improvements in products. Some of the earliest products
of nanoscale technologies (non-MM nanotechnology) include
tennis rackets and golf balls, and such things will quickly
be replaced by nano-built versions. But there are other forms
of recreation as well. Video games and television absorb
a huge percentage of people's time. Better output devices
and faster computers will quickly make it possible to provide
users with a near-reality level of artificial visual and
auditory stimulus. However, even this relatively simple application
may be slowed by the need for
interoperability: high-definition television has suffered
substantial delays for this reason.
A third category of recreation is neurotechnology, usually
in the form of drugs such as alcohol and cocaine. The ability
to build devices smaller than cells implies the possibility
of more direct forms of neurotechnology. However, safe and
legal uses of this are likely to be quite slow to develop.
Even illegal uses may be slowed by a lack of imagination
and understanding of the brain and the mind. A more mundane
problem is that early MM may be able to fabricate only a
very limited set of molecules, which likely will not include
neurotransmitters.
Medical care will be a key beneficiary of molecular manufacturing.
Although the human body and brain are awesomely complex,
MM will lead to rapid improvement in the treatment of many
diseases, and before long will be able to treat almost
every disease, including most or all causes of aging. The
first aspect of medicine to benefit may be minimally invasive
tests. These would carry little risk, especially if key
results were verified by existing tests until the new technology
were proved.
Even with a conservative approach, inexpensive continuous
screening for a thousand different biochemicals could give
doctors early indications of disease. (Although early MM
may not be able to build a wide range of chemicals, it will
be able to build detectors for many of them.) Such monitoring
also could reduce the consequences of diseases inadvertently
caused by medical treatment by catching the problem earlier.
With full-spectrum continuous monitoring of the body's state
of health, doctors would be able to be simultaneously more
aggressive and safer in applying treatments. Individual,
even experimental approaches could be applied to diseases.
Being able to trace the chemical workings of a disease would
also help in developing more efficient treatments for it.
Of course, surgical tools could become far more delicate
and precise; for example, a scalpel could be designed to
monitor the type and state of tissue it was cutting through.
Today, in advanced arthroscopic surgery, simple surgical
tools are inserted through holes the size of a finger; a
nano-built surgical robot with far more functionality could
be built into a device the width of an acupuncture needle.
In the United States today, medical care is highly regulated,
and useful treatments are often delayed by many years. Once
the technology becomes available to perform continuous monitoring
and safe experimental treatments, either this regulatory
system will change, or the U.S. will fall hopelessly behind
other countries. Medical technologies that will be hugely
popular with individuals but may be opposed by some policy
makers, including anti-aging, pro-pleasure, and reproductive
technologies, will probably be developed and commercialized
elsewhere.
Basic needs, in the sense of food, water, clothing, shelter,
and so on, will be easy to provide with even minimal effort.
All of these necessities, except food, can be supplied with
simple equipment and structures that require little innovation
to develop. Although directly manufacturing food will not
be so simple, it will be easy to design and create greenhouses,
tanks, and machinery for growing food with high efficiency
and relatively little labor. The main limitation here is
that without cleverness applied to background information,
system development will be delayed by having to wait for
many growing cycles. For this reason, systems that incubate
separated cells (whether plant, animal, or
algae) may be developed more quickly than systems that grow
whole plants.
The environment already is being impacted as a byproduct
of human activities, but molecular manufacturing will provide
opportunities to affect it deliberately in positive ways.
As with medicine, improving the environment will have to
be done with careful respect for the complexity of its systems.
However, also as with medicine, increased ability to monitor
large areas or volumes of the environment in detail will
allow the effects of interventions to be known far more quickly
and reliably.
This alone will help to reduce accidental damage. Existing
damage that requires urgent remediation will in many cases
be able to be corrected with far fewer side effects.
Perhaps the main benefit of molecular manufacturing for
environmental cleanup is the sheer scale of manufacturing
that will be possible when the supply of nanofactories is
effectively unlimited. To deal with invasive species, for
example, it may be sufficient to design a robot that physically
collects and/or destroys the organisms. Once designed and
tested, as many copies as required could be built, then deployed
across the entire invaded range, allowed to work in parallel
for a few days or weeks, and then collected. Such systems
could be sized to their task, and contain monitoring apparatus
to minimize unplanned impacts.
Because robots would be lighter than humans and have better
sensors, they could be designed to do significantly less
damage and require far fewer resources than direct human
intervention. However, robotic navigation software is not
yet fully developed, and it will not be trivial even with
million-times better computers. Furthermore, the mobility
and power supply of small robots will be limited. Cleanup
of chemical contamination in soil or groundwater also may
be less amenable to this approach without significant disruption.
Advanced military technology may have an immense impact
on our future.
It seems clear that even a modest effort at developing nano-built
weapon systems will create systems that will be able to totally
overwhelm today's systems and soldiers. Even something as
simple as multi-scale semi-automated aircraft could be utterly
lethal to exposed soldiers and devastating to most equipment.
With the ability to build as many weapons as desired, and
with motors, sensors, and materials that far outclass biological
equivalents, there would be no need to put soldiers on the
battlefield at all. Any military operation that required
humans to accompany its machines would quickly be overcome.
Conventional aircraft could also be out-flown and destroyed
with ease. In addition to offensive weapons, sensing and
communications networks with millions if not billions of
distributed components could be built and deployed.
Software design for such things would be far from trivial,
however.
It is less clear that a modest military development effort
would be able to create an effective defense against today's
high-tech attack systems.
Nuclear explosives would have to be stopped before the explosion,
and intercepting or destroying missiles in flight is not
easy even with large quantities of excellent equipment. Hypersonic
aircraft and battle lasers are only now being developed,
and may be difficult to counter or to develop independently
without expert physics knowledge and experience. However,
even a near parity of technology level would give the side
with molecular manufacturing a decisive edge in a non-nuclear
exchange, because they could quickly build so many more weapons.
It is also uncertain what would happen in an arms race between
opponents that both possessed molecular manufacturing. Weapons
would be developed very rapidly up to a certain point. Beyond
that, new classes of weapons would have to be invented. It
is not yet known whether offensive weapons will in general
be able to penetrate shields, especially if the weapons of
both sides are unfamiliar to their opponents. If shields
win, then development of defensive technologies may proceed
rapidly until all sides feel secure. If offense wins, then
a balance of terror may result.
However, because sufficient information may allow any particular
weapon system to be shielded against, there may be an incentive
to continually develop new weapons.
This essay has focused on the earliest applications of molecular
manufacturing. Later developments will benefit from previous
experience, as well as from new software tools such as genetic
algorithms and partially automated design. But even a cursory
review of the things we can plan for today and the problems
that will be most limiting early in the technology's history
shows that molecular manufacturing will rapidly revolutionize
many important areas of human endeavor.
