CRN Task Force Progress
The July announcement of an initiative to create a Technology Roadmap for
Productive Nanosystems (see above) motivated CRN to organize a parallel process
of study and action: the CRN Global Task Force on Implications and Policy.
Bringing together a diverse group of world-class experts from multiple
disciplines, CRN is leading an historic, collaborative effort to develop
comprehensive recommendations for the safe and responsible use of molecular
manufacturing.
We now have more than 50
participants from six different countries on the CRN Task Force. Currently,
the group is working on a series of short essays to identify specific concerns
that must be addressed. When these are published in anthology form early next
year, we will ask for feedback on our ideas, as well as public input on
additional concerns.
Milestones & Moving
Forward
As CRN approaches our 3rd anniversary, we are proud of what we've accomplished
so far, but mindful that greater challenges await us in 2006. This is important
work that few others are doing. To keep moving forward, we will need to grow
fast.
A new page on our
website lists some of the significant milestones from CRN's first three years.
That page also outlines our current priorities—including research, outreach, and
development—and suggests several ways in which you can help advance this work.
Feature Essay: Notes on Nanofactories
Chris Phoenix, Director of Research, Center for Responsible Nanotechnology
This month's science essay is prompted by several questions about nanofactories
that I've received over the past few months. I'll discuss the way in which
nanofactories combine nanoscale components into large integrated products; the
reason why a nanofactory will probably take about an hour to make its weight in
product; and how to cool a nanofactory effectively at such high production
rates.
In current nanofactory designs, sub-micron components are made at individual
workstations and then combined into a product. This requires some engineering
above and beyond what would be needed to build a single workstation. Tom Craver,
on
our blog, suggested that there might be a transitional step, in which
workstations are arranged in a two-dimensional sheet and make a thin sheet of
product. The sheet of manufacturing systems would not have to be flat; it could
be V-folded, and perhaps a solid product could be pushed out of a V-folded
arrangement of sheets. With a narrow folding angle, the product might be
extruded at several times the mechanosynthetic deposition rate.
Although the V-fold idea is clever, I think it's not necessary. Once you can
build mechanosynthetic systems that can build sheets of product, you're most of
the way to a 3D nanofactory. For a simple design, each workstation produces a
sub-micron "nanoblock" of product (each dimension being the thickness of the
product sheet) rather than a connected sheet of product. Then you have the
workstations pass the blocks "hand over hand" to the edge of the workstation
sheet. In a primitive nanofactory design, much of the operational complexity
would be included in the incoming control information rather than the
nanofactory's hardware. This implies that each workstation would have a
general-purpose robot arm or other manipulator capable of passing blocks to the
next workstation.
After the blocks get to the edge of the sheet, they are added to the product.
Instead of the product being built incrementally at the surface of V-folded
sheets, the sheets are stacked fully parallel, just like a ream of paper, and
the product is built at the edge of the ream.
Three things will limit the product ‘extrusion’ speed:
- The block delivery speed. This would be about 1 meter per
second, a typical speed for mechanisms at all scales. This is not a
significant limitation.
- The speed of fastening a block in place. Even a
100-nanometer block has plenty of room for nanoscale mechanical fasteners that
can basically just snap together as fast as the blocks can be placed.
Fasteners that work by molecular reactions could also be fast.
- The width (or depth, depending on your point of view) of
the sheet: how many workstations are supplying blocks to each
workstation-width edge-of-sheet. The width of the sheet stack is limited by
the ability to circulate cooling fluid, but it turns out that even micron-wide
channels can circulate fluid for several centimeters at moderate pressure. So
you can stack the sheets quite close together, making a centimeter-thick slab.
With 100-nanometer workstations, that will have several thousand workstations
supplying each 100-nanometer-square edge-of-stack area. If a workstation takes
an hour to make a 100-nanometer block, then you're depositing several
millimeters per hour. That's if you build the product solid; if you provide a
way to shuffle blocks around at the product-deposition face, you can include
voids in the product, and 'extrude' much faster; perhaps a mm per second.
Tom pointed out that a nanofactory that built products by
block deposition would require extra engineering in several areas, such as block
handling mechanisms, block fasteners, and software to control it all. All this
is true, but it is the type of problem we have already learned to solve. In some
ways, working with nanoblocks will be easier than working with today's
industrial robots; surface forces will be very convenient, and gravity will be
too weak to cause problems.
On the same blog post, Jamais Cascio
asked why I keep saying that a nanofactory will take about an hour to make
its weight of product. The answer is simple: If the underlying technology is
much slower than that, it won't be able to build a kilogram-scale nanofactory in
any reasonable time. And although advanced nanofactories might be somewhat
faster, a one-hour nanofactory would be revolutionary enough.
A one-kilogram one-hour nanofactory could, if supplied with enough feedstock and
energy, make thousands of tons of nanofactories or products in a single day. It
doesn't much matter if nanofactories are faster than one hour (3600 seconds).
Numbers a lot faster than that start to sound implausible. Some bacteria can
reproduce in 15 minutes (900 seconds). Scaling laws suggest that a 100-nm
scanning probe microscope can build its mass in 100 seconds. (The
non-manufacturing overhead of a nanofactory—walls, computers, and so on—would
probably weigh less than the manufacturing systems, imposing a significant but
not extreme delay on duplicating the whole factory.) More advanced
molecule-processing systems could, in theory, process their mass even more
quickly, but with reduced flexibility.
On the slower side, the first nanofactory can't very well take much longer than
an hour to make its mass, because if it did, it would be obsoleted before it
could be built. It goes like this: A nanofactory can only be built by a smaller
nanofactory. The smallest nanofactory will have to be built by very difficult
lab work. So you'll be starting from maybe a 100-nm manufacturing system (10-15
grams) and doubling sixty times to build a 103 gram nanofactory. Each
doubling takes twice the make-your-own-mass time. So a one-hour nanofactory
would take 120 hours, or five days. A one-day nanofactory would take 120 days,
or four months. If you could double the speed of your 24-hour process in two
months (which gives you sixty day-long "compile times" to build increasingly
better hardware using the hardware you have), then the half-day nanofactory
would be ready before the one-day nanofactory would.
Tom Craver pointed out that if the smaller nanofactory can be incorporated into
the larger nanofactory that it's building, then doubling the nanofactory mass
would take only half as long. So, a one-day nanofactory might take only two
months, and a one-hour nanofactory less than three days. Tom also pointed out
that if a one-day tiny-nanofactory is developed at some point, and its size is
slowly increased, then when the technology for a one-hour nanofactory is
developed, a medium-sized one-hour nanofactory could be built directly by the
largest existing one-day nanofactory, saving part of the growing time.
In my "primitive
nanofactory" paper, which used a somewhat inefficient physical architecture
in which the fabricators were a fraction of the total mass, I computed that a
nanofactory on that plan could build its own mass in a few hours. This was using
the Merkle pressure-controlled fabricator, (see "Casing
an Assembler"), with a single order of magnitude speedup to go from pressure
to direct drive.
In summary, the one-hour estimate for nanofactory productivity is probably
within an order of magnitude of being right.
The question about cooling a nanofactory was asked at a talk I gave a few weeks
ago, and I don't remember who asked it. To build a kilogram per hour of diamond
requires rearranging on the order of 1026 covalent bonds in an hour.
The bond energy of carbon is approximately 350 kJ/mol, or 60 MJ/kg. Spread over
an hour, that much energy would release 16 kilowatts, about as much as a plug-in
electric heater.
Of course, you don't want a nanofactory to glow red-hot. And the built-in
computers that control the nanofactory will also generate quite a bit of
heat--perhaps even more than the covalent reactions themselves. So, fluid
cooling looks like a good idea. It turns out that, although the inner features
of a nanofactory will be very small—on the order of one micron—cooling fluid can
be sent for several centimeters down a one-micron channel with only a modest
pressure drop. This means that the physical architecture of the nanofactory will
not need to be adjusted to accommodate variable-sized tree-structured cooling
pipes.
In the years I have spent thinking about nanofactory design, I have not
encountered any problem that could not be addressed with standard engineering.
Of course, engineering in a new domain will present substantial challenges and
require a lot of work. However, it is not safe to assume that some unexpected
problem will arise to delay nanofactory design and development. As work on
enabling technologies progresses, it is becoming increasingly apparent that
nanofactories can be addressed as an integration problem rather than a
fundamental research problem. Although their capabilities seem futuristic, their
technology may be available before most people expect it.
C-R-Newsletter #34 October 16, 2005
Major
Advances in Nanoscale Engineering
New Technical Information
Freely Available
CRN Task Force Progress
Report
Dark Visions of a Fantastic
Future
CRN Interviewed re
Military Nanotechnology
CRN Gets Podcasted
We're on CNET’s Blog 100 List
CRN Goes to Chicago, Again
CRN Goes to San
Francisco
CRN Goes to Michigan
CRN Goes to Seattle
Feature Essay: Early
Applications of Molecular Manufacturing
=========
What a whirlwind! We'll fill
you in on recent events here, but to keep up with the latest happenings on a
daily basis, be sure to check our
Responsible Nanotechnology weblog.
Also, please notice the
FUNDRAISING
ALERT at the end of this newsletter.
Major Advances in Nanoscale Engineering
There are several
possible paths to molecular manufacturing. Eric Drexler favors starting with
biopolymer-based systems and improving them incrementally. Robert Freitas and
Ralph Merkle propose using scanning probe microscopes to do direct
mechanosynthesis of diamondoid systems. Another researcher, Josh Hall, favors a
third path: using a more traditional machining approach to build small systems
that can perform increasingly precise operations, similar to what was originally
proposed by
Richard Feynman.
Exciting work at Northwestern University could significantly improve the
chances of the third approach succeeding. Researchers there recently designed a
tiny sensitive system for applying and sensing force, had samples welded to the
device using a new and very powerful nanoscale manufacturing system, then put
the device in a tunneling electron microscope (TEM) and watched the tube while
they pulled it apart.
Although nothing in this work is atomically precise (with the possible exception
of the TEM microscopy), it's getting close. The ability to integrate MEMS,
nano-manipulation, FIB, and SEM in a single manufacturing system opens a vast
new array of experiments and adds a powerful new part to the
nanotech toolbox.
New Technical Information Freely Available
Now posted online is "Design and Analysis of a Molecular Tool for Carbon
Transfer in Mechanosynthesis" [PDF]
by Damian G. Allis and K. Eric Drexler. This important new paper introduces a
novel carbon-transfer tool design (named "DC10c"), the first predicted to
exhibit several significant properties in combination.
Also
available online is Kinematic Self-Replicating Machines by Robert A.
Freitas Jr. and Ralph C. Merkle. This is the most comprehensive review ever
published about self-replicating machine systems, specifically kinematic
self-replicating machines: systems in which actual physical objects, not mere
patterns of information, undertake their own replication.
The book presents for the first time a detailed 137-dimensional map of the
entire kinematic replicator design space to assist future engineering efforts.
It has been cited in two articles appearing in the journal Nature this
year and appears well on its way to becoming the classic reference in the field.
It's important to note that most of the systems described in KSRM are
only self-replicating in the sense that a set of blacksmith's tools is
self-replicating. The machinery can be used to make a physical copy, but only
under external control, and/or with artificially processed feedstock. Although
runaway independent self-replication has often been cited as a
theoretical danger, it is
not a risk of currently planned molecular manufacturing development.
CRN Task Force Progress Report
Recently CRN announced
the formation of a new Global Task Force to study the societal implications of
advanced nanotechnology. Bringing together a diverse group of world-class
experts from multiple disciplines, CRN is leading an historic, collaborative
effort to develop comprehensive recommendations for the safe and responsible use
of molecular manufacturing.
We're now up to 45 participants from six different countries on the CRN Task
Force. In addition, four organizations are publicly supporting this effort: the
Society of Manufacturing Engineers, the Society of Police Futurists
International, the Nanoethics Group, and the Nanotechnology Now web portal.
Currently underway is a major effort to identify and classify the most important
questions to be asked and answered in order to propose workable solutions to the
challenges posed by this powerful new technology. We expect to publish our
initial findings around the end of this year.
Dark Visions of a Fantastic Future
Flying cars are
everywhere… large regions of the earth are under transparent domes with
controlled weather… elsewhere, single buildings rise miles into the sky… huge
areas of the ocean are covered with solar cells… tiny cameras watch everyone
everywhere all the time, making sure crime does not pay…
In the near future, each of
these visions will become possible. They could become reality. But will they?
And should they?
That's from "Dark Visions of
a Fantastic Future," a
new essay written by CRN Executive Director Mike Treder for Future Brief.
Here is the final paragraph:
Visions of a fantastic
future could come true in our lifetimes. As we dream of the wonderful
possibilities, we should take care also to envision darker scenarios. Because
unless we can prevent the worst of the dangers—and there are many—we will deny
ourselves any hope of realizing the benefits.
CRN Interviewed re Military Nanotechnology
For their most recent monthly report, a special issue on "Nanotechnology and the
Military," Nanotech-Now.com interviewed CRN's Chris Phoenix and Mike
Treder. Under the heading of "Considering Military and Homeland Security
Applications of Advanced Nanotechnology," they published
our thoughts about automated weapons, arms races, surveillance and privacy,
economic disruption, and more.
CRN Gets Podcasted
A podcast program called Small World conducted
an interview this month with CRN Executive Director Mike Treder. Topics
covered were the various definitions of nanotechnology; practical applications
of nanotechnology today and in the near future; nanofactories; the impact of
nanotechnology on the economy; military and terrorist use of nanotechnology; the
National Nanotechnology Initiative; and much more. The completed feature is
about 20 minutes long and can be
downloaded online.
We're on CNET's Blog 100 List
With more than 14 million blogs in existence and another 80,000 being created
each day, how is a person supposed to find the ones worth reading? That's the
question asked by CNET News.com, and they answer it with their
Blog 100 list.
We are very proud that our
Responsible Nanotechnology blog was chosen by CNET News. It's quite an honor
to be ranked in the top 100 technology-oriented blogs among such stiff
competition. We will strive to remain worthy of this recognition.
CRN Goes to Chicago, Again
CRN's Chris Phoenix
gave a talk called "What is nanotechnology? And what does it have to do with
assembly technology?" at the Assembly Technology Expo in Chicago last month
(Mike Treder was in Chicago two months ago for the World Future Society's annual
meeting). Chris explained how and why molecular manufacturing goes far beyond
molecular "self-assembly" techniques.
CRN Goes to San Francisco
CRN is proud to be a media sponsor for the
13th Foresight Conference on Advanced Nanotechnology. The title of the
conference this year is "Advancing Beneficial Nanotechnology: Focusing on the
Cutting Edge," and it will be divided into three stand-alone, complementary
sessions — Vision, Applications & Policy, and Research — spread over six days.
During the "Vision" session on Sunday,
Chris Phoenix will deliver a talk titled "Designing a Revolution." The
conference is October 22-27, 2005, in San Francisco, California. They've
got a great lineup of speakers, so we hope to see you there.
CRN Goes to Michigan
From San Francisco, Chris Phoenix will fly to Michigan where he will address the
1st International IFAS
Conference on Nanotechnology, sponsored by Michigan State University's
Agrifood Nanotechnology Project. The conference will focus on what nanotech and
nanofood can learn from biotech and GMOs. Chris will be part of a concluding
panel discussion.
CRN Goes to Seattle
From Michigan, Chris Phoenix will fly to Seattle where he will address the SAMPE
(Society for the Advancement of Material and Process Engineering)
Fall Technical Conference. Chris will participate in a panel discussion on
occupational safety issues related to nanotechnology.
Feature Essay: Early Applications of Molecular
Manufacturing
Chris Phoenix, Director of Research, Center for Responsible Nanotechnology
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.
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.
* * * * * * * * * * * * * * * *
FUNDRAISING ALERT!
Recent developments in efforts to
roadmap the technological
steps towards molecular manufacturing make the work of CRN even more important.
It is critical that we examine the global implications of this rapidly emerging
technology, and begin designing wise and effective policy. That's why we have
formed the CRN Task Force.
But it won't be easy. We need to grow, and rapidly, to meet the expanding
challenge.
Your donation to CRN will help us to achieve that growth. We rely largely on
individual donations and small grants for our survival.
To make a contribution on-line,
click here.
This is important work and we welcome your participation.
Thank you!
* * * * * * * * * * * * * * * *
C-R-Newsletter #33 August 31, 2005
CRN Forms
Policy Task Force
Eric Drexler Joins Nanorex
Connecticut Schools Go
Nano
NASA Website Covers CRN Work
CRN Goes to Vermont
CRN Goes to Chicago
CRN Goes to Bootcamp
Dimensions of Development
13th Foresight Conference
Feature Essay: Molecular
Manufacturing Design Software
=========
We're a
little late getting the C-R-Newsletter out this month, but as you can see, we've
been extremely busy. To keep up with the latest happenings on a daily
basis, be sure to check our
Responsible Nanotechnology weblog.
CRN Forms Policy Task Force
The big news this month is
that CRN announced
the formation of a new Global Task Force to study the societal implications of
advanced nanotechnology.
Bringing together a diverse group of world-class experts from multiple
disciplines, CRN will lead an historic, collaborative effort to develop
comprehensive policy recommendations for the safe and responsible use of
molecular manufacturing.
Just two weeks after the
initial announcement, which mentioned four "charter members" of the CRN Task
Force, we're up to 39 participants from six different countries. In addition,
three organizations are publicly supporting this effort: the Society of
Manufacturing Engineers, the Society of Police Futurists International, and the
Nanotechnology Now web portal.
Several online planning
sessions have been held, and the CRN Task Force is now beginning its initial
task: to itemize the necessary information that must be available in order to
design wise and effective policy.
Eric Drexler Joins Nanorex
Nanorex, a molecular
engineering software company based in Michigan, has named
Dr. K. Eric Drexler as the company's Chief Technical Advisor.
The company said that Drexler will play a leading role in shaping Nanorex's
product strategy and advancing the company’s academic outreach programs.
Often described as the 'father of
nanotechnology', Eric Drexler is on the
Board of Advisors
for CRN. His groundbreaking theoretical research has been the basis for three
books, including
Nanosystems: Molecular Machinery, Manufacturing, and Computation, and
numerous journal articles. Last year, he collaborated with Chris Phoenix, CRN's
Director of Research, on "Safe
Exponential Manufacturing", published in the Institute of Physics journal
Nanotechnology.
In 1986, Drexler founded the
Foresight Nanotech Institute, a non-profit think tank and public interest
organization focused on nanotechnology. He was awarded a PhD from MIT in
Molecular Nanotechnology (the first degree of its kind). Drexler is expected to
be deeply involved in the project to develop a
Technology Roadmap for Productive Nanosystems, recently announced by
Foresight and the Battelle research organization.
Connecticut Schools Go Nano
Connecticut Governor M.
Jodi Rell has enacted a
new law requiring the Commissioner of Higher Education in her state to
review the inclusion of nanotechnology, molecular manufacturing and advanced and
developing technologies at institutions of higher education.
CRN is pleased to note that this measure
specifically designates molecular manufacturing as something that should be
studied for inclusion in the curriculum at institutions of higher education. We
encourage other states -- and indeed, other countries -- to follow Connecticut's
lead.
NASA
Website Covers CRN Work
The NASA Institute for
Advanced Concepts (NIAC), an independent, NASA-funded organization located in
Atlanta, Georgia, was created to promote forward-looking research on radical
space technologies that will take 10 to 40 years to come to fruition. Last year,
NIAC
awarded a grant to Chris Phoenix, CRN's Director of Research, to conduct a
feasibility study of nanoscale manufacturing.
On NASA's website,
an article titled "The
Next Giant Leap" highlights the
work NIAC is funding in nanotechnology research, and includes a description of
the 112-page report Chris presented to them. We congratulate Chris on this
much-deserved recognition.
CRN Goes to Vermont
In late July, CRN principals Mike Treder and
Chris Phoenix were invited to participate in a
special workshop on 'geoethical nanotechnology', held at a beautiful
mountain retreat in Vermont. Our gracious host was Martine Rothblatt, CEO of
United Therapeutics Corporation, and founder of the
Terasem Movement Foundation.
Among those
making presentations were Ray Kurzweil, CEO of Kurzweil Technologies;
Professor Frank Tipler of Tulane University; Douglas Mulhall, author of Our
Molecular Future; and Dr. Barry
Blumberg, a Nobel Prize-winner in medicine and Founding Director of the NASA
Astrobiology Institute. CRN's PowerPoint presentation for the event is available
online
here.
Geoethical nanotechnology is defined as: the
development and implementation under a global regulatory framework of machines
capable of assembling molecules into a wide variety of objects, in a broad range
of sizes, and in potentially vast quantities.
CRN Goes to Chicago
Also in July, CRN Executive Director Mike Treder
gave talks at two events in Chicago. First, at a special
nanotech symposium [PDF], Mike delivered a presentation called "The
Flat Horizon Problem: Nanotechnology on an Upward Slope" [PPT].
Then, during the annual conference of the World
Future Society, Mike made a speech titled, "Do
Sweat the Small Stuff: Why Everyone Should Care About Nanotechnology" [PPT].
The conference,
WorldFuture 2005: Foresight, Innovation, and Strategy, was managed
excellently and enjoyed huge attendance.
CRN Goes to Bootcamp
In mid-July, CRN Research Director Chris Phoenix
spent four days in Washington DC at a
Nano Training Bootcamp sponsored by the ASME. He called it "quite a
brain-stretcher." Topics included quantum mechanics, optics, thermoelectrics,
nanolithography, and much more. Chris provided us with extensive blog reports
during the event, so you can read about all the tech-talk from
Day One,
Day Two,
Day Three, and
Day Four.
Dimensions of Development
Many factors will determine how soon and how
safely molecular manufacturing is integrated
into society, including where, how openly, and how rapidly it is developed.
Because nanotech manufacturing could be so disruptive and destabilizing, it is
essential that we learn as much as possible about those factors and others. The
more we know, the better we may be able to guide and manage this revolutionary
transformation.
Mike Treder's
latest essay for Future Brief describes six different dimensions —
Number, Style, Venue, Approach, Program, and Pace — along which molecular
manufacturing may be developed. Making effective policy for the safe and
responsible use of advanced nanotechnology will require a deep and comprehensive
understanding of all six dimensions. To be effective, a coordinated and
integrated strategy of multiple complimentary policies must be designed and
implemented. (Note: At the time the essay was published, the
CRN Global Task Force on
Implications and Policy had not yet been announced.)
13th Foresight Conference
CRN is proud to be a media sponsor for the
13th Foresight Conference on Advanced Nanotechnology. The title of the
conference this year is "Advancing Beneficial Nanotechnology: Focusing on the
Cutting Edge," and it will be divided into three stand-alone, complementary
sessions — Vision, Applications & Policy, and Research — spread over six days.
The conference is October 22-27, 2005, in San
Francisco, California. They've got a great lineup of speakers, so we hope to see
you there.
Feature Essay:
Molecular
Manufacturing Design Software
Chris Phoenix, Director of Research, CRN
Nanofactories, controlled by computerized blueprints, will be able to build a
vast range of high performance products. However, efficient product design will
require advanced software.
Different
kinds of products will require different approaches to design. Some, such as
high-performance supercomputers and advanced medical devices, will be packed
with functionality and will require large amounts of research and invention. For
these products, the hardest part of design will be knowing what you want to
build in the first place. The ability to build test hardware rapidly and
inexpensively will make it easier to do the necessary research, but that is not
the focus of this essay.
There are
many products that we easily could imagine and that a nanofactory easily could
build if told exactly how. But as any computer programmer knows, it's not easy
to tell a computer what you want it to do — it's more or less like trying to
direct a blind person to cook a meal in an unfamiliar kitchen. One mistake, and
the food is spilled or the stove catches fire.
Computer
users have an easier time of it. To continue the analogy, if the blind person
had become familiar with the kitchen, instructions could be given on the level
of "Get the onions from the left-hand vegetable drawer" rather than "Move your
hand two inches to your right... a bit more... pull the handle... bend down and
reach forward... farther... open the drawer... feel the round things?" It is the
job of the programmer to write the low-level instructions that create appliances
from obstacles.
Another
advantage of modern computers, from the user's point of view, is their input
devices. Instead of typing a number, a user can simply move a mouse, and a
relatively simple routine can translate its motion into the desired number, and
the number into the desired operation such as moving a pointer or a scroll bar.
Suppose I
wanted to design a motorcycle. Today, I would have to do engineering to
determine stresses and strains, and design a structure to support them. The
engineering would have to take into account the materials and fasteners, which
in turn would have to be designed for inexpensive assembly. But these choices
would limit the material properties, perhaps requiring several iterations of
design. And that's just for the frame.
Next, I
would have to choose components for a suspension system, configure an engine,
add an electrical system and a braking system, and mount a fuel tank. Then, I
would have to design each element of the user interface, from the seat to the
handgrips to the lights behind the dials on the instrument panel. Each thing the
user would see or touch would have to be made attractive, and simultaneously
specified in a way that could be molded or shaped. And each component would have
to stay out of the way of the others: the engine would have to fit inside the
frame, the fuel tank might have to be molded to avoid the cylinder heads or the
battery, and the brake lines would have to be routed from the handlebars and
along the frame, adding expense to the manufacturing process and complexity to
the design process.
As I
described in last month's essay, most nanofactory-built human-scale products
will be mostly empty space due to the awesomely high performance of both active
and passive components. It will not be necessary to worry much about keeping
components out of each other's way, because the components will be so small that
they can be put almost anywhere. This means that, for example, the frame can be
designed without worrying where the motor will be, because the motor will be a
few microns of nanoscale motors lining the axles. Rather than routing large
hydraulic brake lines, it will be possible to run highly redundant microscopic
signal lines controlling the calipers — or more likely, the regenerative braking
functionality built into the motors.
It will not
be necessary to worry about design for manufacturability. With a planar-assembly
nanofactory, almost any shape can be made as easily as any other, because the
shapes are made by adding sub-micron nanoblocks to selected locations in a
supported plane of the growing product. There will be less constraint on form
than there is in sand casting of metals, and of course far more precision. This
also means that what is built can contain functional components incorporated in
the structure. Rather than building a frame and mounting other pieces later, the
frame can be built with all components installed, forming a complete product.
This does require functional joints between nanoblocks, but this is a small
price to pay for such flexibility.
To specify
functionality of a product, in many cases it will be sufficient to describe the
desired functionality in the abstract without worrying about its physical
implementation. If every cubic millimeter of the product contains a networked
computer — which is quite possible, and may be the default — then to send a
signal from point A to point B requires no more than specifying the points.
Distributing energy or even transporting materials may not require much more
attention: a rapidly rotating diamond shaft can transport more than a watt per
square micron, and would be small enough to route automatically through almost
any structure; pipes can be made significantly smaller if they are configured
with continually inverting liners to reduce drag.
Thus, to
design the acceleration and braking behavior of the motorcycle, it might be
enough to specify the desired torque on the wheels as a function of speed, tire
skidding, and brake and throttle position. A spreadsheet-like interface could
calculate the necessary power and force for the motors, and from that derive the
necessary axle thickness. The battery would be fairly massive, so the user would
position it, but might not have to worry about the motor-battery connection, and
certainly should not have to design the motor controller.
In order to
include high-functionality materials such as motor arrays or stress-reporting
materials, it would be necessary to start with a library of well-characterized
"virtual materials" with standard functionality. This approach could
significantly reduce the functional density of the virtual material compared to
what would be possible with a custom-designed solution, but this would be
acceptable for many applications, because functional density of nano-built
equipment may be anywhere from six to eighteen orders of magnitude better than
today's equipment. Virtual materials could also be used to specify material
properties such as density and elasticity over a wide range, or implement active
materials that changed attributes such as color or shape under software control.
Prototypes
as well as consumer products could be heavily instrumented, warning of
unexpected operating conditions such as excessive stress or wear on any part.
Rather than careful calculations to determine the tradeoff between weight and
strength, it might be better to build a first-guess model, try it on
increasingly rough roads at increasingly high speeds, and measure rather than
calculate the required strength. Once some parameters had been determined, a new
version could be spreadsheeted and built in an hour or so at low cost. It would
be unnecessary to trade time for money by doing careful calculations to minimize
the number of prototypes. Then, for a low-performance application like a
motorcycle, the final product could be built ten times stronger than was thought
to be necessary without sacrificing much mass or cost.
There are
only a few sources of shape requirements. One is geometrical: round things roll,
flat things stack, and triangles make good trusses. These shapes tend to be
simple to specify, though some applications like fluid handling can require
intricate curves. The second source of shape is compatibility with other shapes,
as in a piece that must fit snugly to another piece. These shapes can frequently
be input from existing databases or scanned from an existing object. A third
source of shape is user preference. A look at the shapes of pen barrels, door
handles, and eyeglasses shows that users are pleased by some pretty
idiosyncratic shapes.
To input
arbitrary shapes into the blueprint, it may be useful to have some kind of
interface that implements or simulates a moldable material like clay or taffy. A
blob could simply be molded or stretched into a pleasing shape. Another useful
technique could be to present the designer or user with several variations on a
theme, let them select the best one, and build new variations on that until a
sufficiently pleasing version is produced.
Although there is
more to product design than the inputs described here, this should give some
flavor of how much more convenient it could be with computer-controlled rapid
prototyping of complete products. Elegant computer-input devices, pervasive
instrumentation and signal processing, virtual material libraries, inexpensive
creation of one-off spreadsheeted prototypes, and several other techniques could
make product design more like a combination of graphic arts and computer
programming than the complex, slow, and expensive process it is today.
* * * * * * * * * * * * * * * *
FUNDRAISING ALERT!
Recent developments in efforts to
roadmap the technological
steps towards molecular manufacturing make the work of CRN even more important.
It is critical that we examine the global implications of this rapidly emerging
technology, and begin designing wise and effective policy. That's why we have
formed the CRN Task Force.
But it won't be easy. We need to grow, and rapidly, to meet the expanding
challenge.
Your donation to CRN will help us to achieve that growth. We rely largely on
individual donations and small grants for our survival.
To make a contribution on-line,
click here.
This is important work and we welcome your participation!
* * * * * * * * * * * * * * * *
C-R-Newsletter #32 July 14, 2005
Nanotech Roadmap Initiative
New Nano Movie
Russian CRN Site Online
Nanotech Q&A for Russia
Nano-techno-logy
State of the Future 2005
Nanotechnology Workshop
Webcast
CRN goes to Chicago
Feature Essay: Fast Development
of Nano-Manufactured Products
FUNDRAISING ALERT!
=========
Things are moving very quickly throughout the nano-world and
at CRN. We’ll recap some of the highlights here — but to keep up with the latest
developments, be sure to check our
Responsible Nanotechnology weblog. Thanks!
Nanotech Roadmap Initiative
Foresight Nanotech Institute, in cooperation with Battelle, a global research
organization,
has announced its intent to develop a "Technology Roadmap for Productive
Nanosystems." CRN strongly encourages a cooperative program to map all the steps
that will lead to molecular manufacturing. We have even outlined a
series of studies that
could go a long way toward meeting this goal. A combined effort — involving
business, government, academic, and nonprofit participants — appears safest to
us. This is especially true if numerous international partners are included, the
more the better.
In principle,
we support the idea of a collaborative technical roadmap project. It's not
yet clear, however, if the Foresight announcement meets our description. We look
forward to hearing more about it in the near future.
New Nano Movie
A new "must-see" short film has been produced using computer animation to assist
in visualizing nanosystems and molecular manufacturing. Productive
Nanosystems: from Molecules to Superproducts, is a collaborative effort of
animator and engineer
John Burch and pioneer nanotechnologist
Dr. K. Eric Drexler, made possible through a challenge grant from
Mark Sims and NanoRex. The four-minute film depicts an animated view of a
nanofactory and demonstrates key steps in a process that converts simple
molecules into a billion-CPU laptop computer. The
movie file is 60+ MB. It will take a while to download, but it's definitely
worth it.
Russian CRN Site Online
CRN is very pleased to announce that several pages from our main website have
been translated into the Russian language and
are posted on the Internet.
Denis Tarasov, a Research Scientist in the Biology Department of
Kazan
State University in Russia, did most of the translation work. We are
grateful for his assistance.
We now have CRN web pages available in five languages: English,
Chinese,
Spanish,
Portuguese, and
Russian. If you think you can help with other languages, please
let us know.
Nanotech Q&A for Russia
Last month, NanoNewsNet, a web portal for nanotechnology news and
research in Russia, interviewed CRN Executive Director
Mike Treder
for their site. The interview is
posted online in the Russian language. We have an English translation
here.
Nano-techno-logy
Three Greek words — nano (dwarf or tiny), techne (craft or skill), and logos
(science or learning) — combine to make nano-techno-logy: applying science at a
tiny scale to the craft or skill of building. Miracle predictions about
nanotech's potential are common, as are dire warnings about the technology's
risks. So, are the pessimists or the optimists right?
To find out, read this
new essay by Mike Treder, published by Future Brief.
State of the Future 2005
Many people still do not appreciate how fast science and technology will change
over the next 25 years, and given this rapid development along several different
fronts, the possibility of technology growing beyond human control must now be
taken seriously, according to
a new report produced by the United Nations University's
Millennium Project.
State of the Future 2005 analyzes current global trends and examines in
detail some of the present and future challenges facing the world. As a
consultant to the UN University's Millennium Project, CRN’s Mike Treder was
involved with developing
some of the findings contained in the report.
Nanotechnology Workshop Webcast
The Terasem Movement, Inc., a non-profit foundation focused on geoethical
nanotechnology, has announced that an
interactive webcast featuring Ray Kurzweil, Frank Tipler, James Hughes, Max
More, Doug Mulhall, Mike Treder and others at its
Geoethical Nanotechnology Workshop will be openly accessible from 8AM-6PM
EST on Wednesday, July 20th.
Viewers of the interactive webcast are invited to email or IM (instant-message)
questions directed to the presenters throughout the meeting. Each hour, some of
these will be selected for the featured speakers to answer. The webcast will
feature simultaneous transmission of audio, video, and PowerPoint presentations.
Geoethical nanotechnology is the development and implementation under a global
regulatory framework of machines capable of assembling molecules into a wide
variety of objects, in a broad range of sizes, and in potentially vast
quantities.
CRN goes to Chicago
CRN's Mike Treder is speaking at two events in Chicago later this month. On
Friday, July 29, at a special
Symposium on Nanotechnology [PDF], Mike will deliver a presentation called
"The Flat Horizon Problem: Nanotechnology on an Upward Slope."
The next day, Saturday, July 30, during the annual conference of the World
Future Society, Mike is giving a talk titled, "Do Sweat the Small Stuff: Why
Everyone Should Care About Nanotechnology." The conference,
WorldFuture 2005: Foresight, Innovation, and Strategy, is at the Chicago
Hilton and Towers. If you're going to be there, make sure to say hello to Mike.
Feature Essay: Fast Development of Nano-Manufactured
Products
Chris Phoenix, Director of Research, Center for Responsible Nanotechnology
The extremely high performance of the products of
molecular manufacturing will make the technology transformative—but it is
the potential for fast development that will make it truly disruptive. If
it took decades of research to produce breakthrough products, we would have time
to adjust. But if breakthrough products can be developed quickly, their
effects can pile up too quickly to allow wise policymaking or adjustment. As if
that weren't bad enough, the anticipation of rapid development could cause
additional problems.
How quick is "quickly?" Given a programmable factory that can make a product
from its design file in a few hours, a designer could create a newly improved
version every day. Today, building prototypes of a product can take weeks, so
designers have to take extra time to double-check their work. If building a
prototype takes less than a day, it will often be more efficient to build and
test the product rather than taking time to double-check the theoretical design.
(Of course, if taken to extremes, this can encourage sloppy work that costs more
time to fix in the long run.)
In addition to being faster, prototyping also would be far cheaper. A
nanofactory would go
through the same automated operations for a single prototype copy as for a
production run, so the prototype should cost no more per unit than the final
product. That's quite a contrast with today, where rapid prototyping can cost
thousands of dollars per component. And it means that destructive testing will
be far less painful. Let's take an example. Today, a research rocket might cost
hundreds of dollars to fuel, but hundreds of thousands to build. At that rate,
tests must be held to a minimum number, and expensive and time-consuming efforts
must be made to eliminate all possible sources of failure and gather as much
data as possible from each test. But if the rocket cost only hundreds of dollars
to build—if a test flight cost less than $1000, not counting support
infrastructure—then tests could be run as often as convenient, requiring far
less support infrastructure, saving costs there as well. The savings ripple out:
with less at stake in every test, designers could use more advanced and less
well-proved technologies, some of which would fail but others of which would
increase performance. Not only would the product be developed faster, but it
also would be more advanced, and have a lot more testing.
The equivalence between prototype and production manufacturing has an additional
benefit. Today, products must be designed for two different manufacturing
processes—prototyping and scaled-up production. Ramping up production has its
own costs, such as rearranging production lines and training workers. But with
direct-from-blueprint building, there would be no need to keep two designs in
mind, and also no need to expend time and money ramping up production. When a
design was finalized, it could immediately be shipped to as many nanofactories
as desired, to be built efficiently and almost immediately. (For those just
joining us, the reason nanofactories aren't scarce is that a nanofactory would
be able to build another nanofactory on command, needing only data and supplies
of a few refined chemicals.) A product design isn't really proved until people
buy it, and rolling out a new product is expensive and risky today—after
manufacture, the product must be shipped and stored in quantity, waiting for
people to buy it. With last-minute nanofactory manufacturing, the product
rollout cost could be much lower, reducing the overhead and risk of
market-testing new ideas.
There are several other technical reasons why products could be easier to
design. Today's products are often crammed full of functionality, causing severe
headaches for designers trying to make one more thing fit inside the package.
Anyone who's looked under the hood of a 1960 station wagon and compared it with
a modern car's engine, or studied the way chips and wires are packed into every
last nook and cranny of a cell phone, knows how crowded products can get. But
molecular manufactured products will be many orders of magnitude more compact;
this is true for sensors, actuators, data processing, energy transformation, and
even physical structure. What this means is that any human-scale product will be
almost entirely empty space. Designers will be able to include functions without
worrying much about where they will physically fit into the product. This
ability to focus on function will simplify the designer's task.
The high performance of molecularly precise nanosystems also means that
designers can afford to waste a fair amount of performance in order to simplify
the design. For example, instead of using a different size of motor for every
different-sized task, designers might choose from only two or three standard
sizes that might differ from each other by an order of magnitude or more. In
today's products, using a thousand-watt motor to do a hundred-watt motor's job
would be costly, heavy, bulky, and probably an inefficient use of energy
besides. But nano-built motors have been calculated to be at least a million
times as powerful. That thousand-watt motor would shrink to the size of a grain
of sand. Running it at low power would not hurt its efficiency, and it wouldn't
be in danger of overheating. It wouldn't cost significantly more to build than a
carefully-sized hundred-watt motor. And at that size, it could be placed
wherever in the product was most convenient for the designer.
Another potential advantage of having more performance than needed is that
design can be performed in stages. Instead of planning an entire product at
once, integrated from top to bottom, designers could cobble together a product
from a menu of lower-level solutions that were already designed and understood.
For example, instead of a complicated system with lots of custom hardware to be
individually specified, designers could find off-the-shelf modules that had more
features than required, string them together, and tweak their specifications or
programming to configure their functionality to the needed product—leaving a lot
of other functionality unused. Like the larger-than-necessary motor, this
approach would include a lot of extra stuff that was put in simply to save the
designer's time; however, including all that extra stuff would cost almost
nothing. This approach is used today in computers. A modern computer spends at
least 99% of its time and energy on retroactively saving time for its designers.
In other words, the design is horrendously inefficient, but because computer
hardware is so extremely fast, it's better to use trillions of extra
calculations than to pay the designer even $10 to spend time on making the
program more efficient. A modern personal computer does trillions of
calculations in a fraction of an hour.
Modular design depends on predictable modules—things that work exactly as
expected, at least within the range of conditions they are used in. This is
certainly true in computers. It will also be true in molecular manufacturing,
thanks to the digital nature of covalent bonds. Each copy of a design that has
the same bond patterns between the atoms will have identical behavior. What this
means is that once a modular design is characterized, designers can be quite
confident that all subsequent copies of the design will be identical and
predictable. (Advanced readers will note that isotopes can make a difference in
a few cases, but isotope number is also discrete and isotopes can be sorted
fairly easily as necessary to build sensitive designs. Also, although radiation
damage can wipe out a module, straightforward redundancy algorithms will take
care of that problem.)
With all these advantages, development of nano-built products, at least to the
point of competing with today's products, appears to be easier in some important
ways than was development of today's products. It's worth spending some thought
on the implications of that. What if the military could test-fire a new missile
or rocket every day until they got it right? How fast would the strategic
balance of power shift, and what is the chance that the mere possibility of such
a shift could lead to pre-emptive military strikes? What if doctors could build
new implanted sensor arrays as fast as they could find things to monitor, and
then use the results to track the effects of experimental treatments (also
nano-built rapid-prototyped technology) before they had a chance to cause
serious injury? Would this enable doctors to be more aggressive—and
simultaneously safer—in developing new lifesaving treatments? If new versions of
popular consumer products came out every month—or even every week—and consumers
were urged to trade up at every opportunity, what are the environmental
implications? What if an arms race developed between nations, or between police
and criminals? What if products of high personal desirability and low social
desirability were being created right and left, too quickly for society to
respond? A technical essay is not the best place to get into these questions,
but these issues and more are directly raised by the possibility that molecular
manufacturing nanofactories will open the door to true rapid prototyping.
* * * * * * * * * * * * * * * *
FUNDRAISING ALERT!
Recent developments in efforts to
roadmap the technological
steps towards molecular manufacturing make the work of CRN even more important.
It is critical that we examine the global implications of this rapidly emerging
technology, and CRN continues to be in the forefront of this discussion.
But we need to grow, and rapidly, to meet the expanding need.
Your donation to CRN will help us to achieve that growth. We rely largely on
individual donations and small grants for our survival.
To make a contribution on-line,
click here.
This is important work and we welcome your participation!
* * * * * * * * * * * * * * * *
C-R-Newsletter #31 June 10, 2005
NanoWorld Weapons Warning
Citizen Conferences on
Technology
CRN Policy Debate
Nanofuture: What's Next
for Nanotechnology
CRN goes to Baltimore
Russian Translation Coming
Soon
Reminder about Symposium on
Nanotechnology
Feature Essay: Sudden
Development of Molecular Manufacturing
FUNDRAISING ALERT!
=========
Even more than usual, things are happening fast
at CRN. We'll recap some of the highlights here—but to keep up with the latest
developments, be sure to check our
Responsible Nanotechnology weblog.
NanoWorld Weapons Warning
"Nano could lead to new WMDs"
Does that sound like one of
CRN's warnings? Not this time. It's the headline on a recent UPI article by
Charles Choi, in which he interviews scientists from the University of
Mexico and the University of California.
The scary thing is that
they aren't focusing on advanced nanotechnology -- destructive new devices
produced in mass quantity with molecular manufacturing -- because they don't
have to. They make a convincing point just talking about improved (is that the
right word?) chemical and biological weapons.
Already we're hearing sabers rattle and drums beat with the proposed
weaponization of space. From there, it's a short step to
military use of
molecular machine systems with exponential manufacturing potential -- and at
that point we're right on the edge of a
very steep cliff.
Citizen Conferences on Technology
An
innovative way to "stimulate broad and intelligent social debate on
technological issues," pioneered in the 1980s by the Danish Board of Technology,
is now getting underway
in the UK, with a focus on nanotechnology.
We think this is a good sign.
Public involvement in determining
safe development and
responsible use of advanced nanotechnology will be vital.
CRN research suggests
that these issues are likely to arise
sooner than many expect.
The surest way to avoid the worst dangers is to understand them in advance and
take assertive action to prevent them.
CRN Policy Debate
After reading Executive Director Mike Treder's essay on "War,
Interdependence, and Nanotechnology," C-R-Network member Steve Burgess
engaged Mike in a friendly email 'debate' on nanotechnology policy. The
discussion revolved around instituting fair distribution of nanotech-produced
abundance as a way of preventing an uncontrollable arms race.
Issues covered were: 1) How can such distribution be imposed with a minimum of
force and conflict? 2) Is it even ethical to attempt to impose a global system
of abundance, superseding national sovereignties? 3) Even if the basis for a
society based on lack of scarcity exists in the future, will evolved human
psychology be able to make the transition without widespread fighting?
We posted the back and forth responses
on our blog.
Nanofuture: What's Next for Nanotechnology
Flying cars, space travel for everyone, the elimination of poverty and hunger,
and powerful new tools to combat disease, and even aging. These are some of the
amazing predicted developments of nanotechnology, the coming science of
designing and building machines at the molecular and atomic levels. Will this
new scientific revolution be for better or worse?
That's from the publisher's description of
Nanofuture: What's Next for Nanotechnology, a new nonfiction book by Dr.
J. Storrs (Josh) Hall. We haven't read it yet, but based on the description and
the
rave reviews, this looks like a must-read. We wish Josh great success with
his book.
CRN goes to Baltimore
About 50 engineers and other interested people attended an
Emerging Technologies Forum titled "The Next Industrial Revolution:
Molecular Nanotechnology and Manufacturing" in Baltimore last week. CRN
Executive Director Mike Treder was asked to moderate the event, which was
sponsored by the Society of Manufacturing Engineers (SME). Speakers included
Scott Mize, president of the
Foresight Institute, Dr. Joseph Jacobson from the
Center for Bits and Atoms at MIT, Kevin Lyons of the
National
Science Foundation, Dr. Dennis Swyt of the
NIST, and Dr. Richard Colton from the
U.S. Naval Research Laboratory.
This forum was the second in a series intended to educate the manufacturing
sector about what they can expect from advanced nanotechnology. CRN's Chris
Phoenix spoke at the
first event, which was last month in Minneapolis, Minnesota. We applaud SME
for being forward-looking and helping to prepare their members for the next
industrial revolution.
Russian Translation Coming Soon
We are excited to announce that a volunteer is translating several of CRN's web
pages into the Russian language. Other volunteers from Russia’s
Nanotechnology News Network are helping to edit and verify the
translation.
When this is completed, we will have CRN web pages in
Chinese,
Spanish,
Portuguese, and Russian, in addition to English. Next, we'll be looking for
people to help with translations into Arabic, Bengali, French, German, Hindi,
Japanese, and perhaps other languages. We want everyone to learn about
responsible nanotechnology!
Reminder about Symposium on Nanotechnology
In connection with their hugely popular annual conference, the World Future
Society has announced "an exploration series designed to provide an outline of
several critical new fields with the potential for significant impact on the
social, economic, and cultural fabric of modern society." For this year, they
have organized a
Symposium on Nanotechnology [PDF], which CRN's
Mike Treder
will assist in presenting. It's happening in Chicago on July 29, 2005. Hope to
see you there!
Feature Essay: Sudden Development of Molecular
Manufacturing
Chris Phoenix, Director of Research, Center for Responsible Nanotechnology
Development of molecular manufacturing technology probably will not be gradual,
and will not allow time to react to incremental improvements. It is often
assumed that development must be gradual, but there are several points at which
minor improvements to the technology will cause massive advances in capability.
In other words, at some points, the capability of the technology can advance
substantially without breakthroughs or even much R&D.
These jumps in capability could happen quite close together, given the
pre-design that a well-planned development program would certainly do. Advancing
from laboratory demos all the way to megatons of easily designed, highly
advanced products in a matter of months appears possible. Any policy that will
be needed to deal with the implications of such products must be in place before
the advances start.
The first jump in capability is exponential manufacturing. If a manufacturing
system can build an identical copy, then the number of systems, and their mass
and productivity, can grow quite rapidly. However, the starting point is quite
small; the first device may be one million-billionth of a gram (100 nanometers).
It will take time for even exponential growth to produce a gram of manufacturing
systems. If a copy can be built in a week, then it will take about a year to
make the first gram. A better strategy will be to spend the next ten months in R&D
to reduce the manufacturing time to one day, at which point it will take less
than two months to make the first gram. And at that point, expanding from the
first gram to the first ton will take only another three weeks.
It's worth pointing out here that nanoscale machinery is vastly more powerful
than larger machinery. When a machine shrinks, its power density and functional
density improve. Motors could be a million times more powerful than today's;
computers could be billions of times more compact. So a ton of nano-built stuff
is a lot more powerful than a ton of conventional product. Even though the
products of tiny manufacturing systems will themselves be small, they will
include computers and medical devices. A single kilogram of nanoscale computers
would be far more powerful than the sum of all computers in existence today.
The second jump in capability is nanofactories—integrated manufacturing systems
that can make large products with all the advantages of precise nanoscale
machinery. It turns out that nanofactory design can be quite simple and
scalable, meaning that it works the same regardless of the size. Given a
manufacturing system that can make sub-micron blocks ("nanoblocks"), it doesn't
take a lot of additional work to fasten those blocks together into a product. In
fact, a product of any size can be assembled in a single plane, directly from
blocks small enough to be built by single nanoscale manufacturing systems,
because assembly speed increases as block size decreases. Essentially, a
nanofactory is just a thin sheet of manufacturing systems fastened side by side.
That sheet can be as large as desired without needing a re-design, and the low
overhead means that a nanofactory can build its own mass almost as fast as a
single manufacturing system. Once the smallest nanofactory has been built,
kilogram-scale and ton-scale nanofactories can follow in a few weeks.
The third jump in capability is product design. If it required a triple Ph.D. in
chemistry, physics, and engineering to design a nanofactory product, then the
effects of nanofactories would be slow to develop. But if it required a triple
Ph.D. in semiconductor physics, digital logic, and operating systems to write a
computer program, the software industry would not exist. Computer programming is
relatively easy because most of the complexity is hidden—encapsulated and
abstracted within simple, elegant high-level commands. A computer programmer can
invoke billions of operations with a single line of text. In the case of
nanofactory product design, a good place to hide complexity is within the
nanoblocks that are fastened together to make the product. A nanoblock designer
might indeed need a triple Ph.D. However, a nanoblock can contain many millions
of features—enough for motors, a CPU, programmable networking and connections,
sensors, mechanical systems, and other high-level components.
Fastening a few types of nanoblocks together in various combinations could make
a huge range of products. The product designer would not need to know how the
nanoblocks worked—only what they did. A nanoblock is quite a bit smaller than a
single human cell, and a planar-assembly nanofactory would impose few limits on
how they were fastened together. Design of a product could be as simple as
working with a CAD program to specify volumes to be filled and areas to be
covered with different types of nanoblocks.
Because the internal design of nanoblocks would be hidden from the product
designer, nanoblock designs could be changed or improved without requiring
product designers to be retrained. Nanoblocks could be designed at a functional
level even before the first nanofactory could be built, allowing product
designers to be trained in advance. Similarly, a nanofactory could be designed
in advance at the nanoblock level. Although simple design strategies will cost
performance,
scaling laws indicate that molecular-manufactured machinery will have
performance to burn. Products that are revolutionary by today's standards,
including the nanofactory itself, could be significantly less complex than
either the software or the hardware that makes up a computer—even a 1970's-era
computer.
The design of an exponential molecular manufacturing system will include many of
the components of a nanofactory. The design of a nanofactory likewise will
include components of a wide range of products. A project to achieve exponential
molecular manufacturing would not need much additional effort to prepare for
rapid creation of nanofactories and their highly advanced products.
Sudden availability of advanced products of all sizes in large quantity could be
highly disruptive. It would confer a large military advantage on whoever got it
first, even if only a few months ahead of the competition. This implies that
molecular manufacturing technology could be the focus of a high-stakes arms
race. Rapid design and production of products would upset traditional
manufacturing and distribution. Nanofactories would be simple enough to be
completely automated—and with components small enough that this would be
necessary. Complete automation implies that they will be self-contained and easy
to use. Nanofactory-built products, including nanofactories themselves, could be
as hard to regulate as Internet file-sharing. These and other problems imply
that wise policy, likely including some global-scale policy, will be needed to
deal with molecular manufacturing. But if it takes only months to advance from
100-nanometer manufacturing systems to self-contained nanofactories and
easily-designed revolutionary products, there will not be time to make wise
policy once exponential manufacturing is achieved. We will have to start ahead
of time.
* * * * * * * * * * * * * * * *
FUNDRAISING ALERT!
Recent developments in efforts to roadmap the technological steps towards
molecular manufacturing make the work of CRN even more important.
It is critical that we examine the global implications of this rapidly emerging
technology, and CRN continues to be in the forefront of this discussion.
But we need to grow, and rapidly, to meet the expanding need.
Your donation to CRN will help us to achieve that growth. We rely largely on
individual donations and small grants for our survival.
To make a contribution on-line
click here. This is important work and we welcome your participation.
* * * * * * * * * * * * * * * *
C-R-Newsletter #30 May 11, 2005
CRN goes to Minnesota
Moving Closer to a
Manufacturing Revolution
War, Interdependence, and
Nanotechnology
Nanotechnology Research
Discrepancy?
Responsible Nanotechnology
Report Issued
Reminder about WFS Seminar &
Conference
Feature Essay: Molecular
Manufacturing vs. Tiny Nanobots
CRN Needs Your Help!
=========
As usual, things are happening fast at CRN. We'll recap most
of the highlights here—but to keep up with us on a daily basis, be sure to check
our
Responsible Nanotechnology weblog.
CRN goes to Minnesota
Last week, CRN Director of Research Chris Phoenix, made a presentation at a
unique new conference sponsored by the Society of Manufacturing Engineers (SME).
His talk, "Molecular Manufacturing: Beyond Nanomanufacturing," was based on a
50-page paper (see below) prepared especially for this event.
As far as we know, this is the first meeting ever presented by and for the
manufacturing sector to focus specifically on what they can expect from advanced
nanotechnology. The one-day conference, called "Molecular Nanotechnology and
Manufacturing: The Enabling Tools and Applications," took place May 4 at the
Minneapolis Convention Center.
Moving Closer to a Manufacturing Revolution
Nanotechnology’s long-expected transformation of manufacturing has
just moved closer to reality. A new analysis of existing technological
capabilities, including proposed steps from today's nanotech to advanced
molecular machine systems, has been released by CRN.
The study, "Molecular Manufacturing: What, Why and How," was completed
by Chris Phoenix and is
available online at Wise-Nano.org. It shows how existing technologies can be
coordinated toward a reachable goal of general-purpose molecular manufacturing.
Chris describes two approaches for building the initial basic tools with current
technology. Other sections outline incremental improvement from those early
tools toward the first integrated nanofactory, and analyze a scalable
architecture for a more advanced nanofactory. Product performance and likely
applications are discussed, as well as incentives for corporate or government
investment in the technology. Finally, considerations and recommendations for a
targeted development program are presented.
War, Interdependence, and Nanotechnology
From the dawn of the nuclear age until the present day, we have relied on two
mechanisms to protect us from World War III: the doctrine of Mutually Assured
Destruction (MAD), and the growing interdependence of nations. In the very near
future, we may not be able to count on these controls. The tenuous balance of
MAD and the worldwide network of commercial trade are both threatened by the
rise of advanced nanotechnology.
"War,
Interdependence, and Nanotechnology" is the title of a new essay from CRN
Executive Director Mike Treder, published recently by Future Brief. The
essay ends with a warning that the disruptive and destabilizing implications of
advanced nanotechnology must not be underestimated. This is balanced, however,
with recommendation for studies that may allow many of the near miraculous
benefits to be realized without the worst-case disasters occurring.
Nanotechnology Research Discrepancy?
An
important editorial in the current issue of The New Atlantis
describes what they see as a "discrepancy between what Congress expects [from
nanotechnology research] and what federal funds in fact support."
In reviewing the activities of a National Research Council committee tasked to
evaluate the goals and
progress of the U.S. National Nanotechnology Initiative, the editorial
says...
It is our hope that the committee will offer a clear analysis of the technical
potential of molecular manufacturing, and a clear recommendation on whether
federal nanotechnology funds should be allocated toward theoretical and
practical research into molecular manufacturing.
CRN believes that any serious, unbiased investigation into the steps
required to move from today's nanoscale technologies to exponential
general-purpose molecular manufacturing will conclude that the matter raises
serious implications, and that actions heretofore ignored should be undertaken
with urgency. By that, we mean a well-funded, dedicated program of inquiry
something like our Thirty
Essential Studies.
We hope the NRC committee will agree, and that their recommendation will spur
similar—or, better yet, coordinated—actions from other major governmental and
civil society organizations around the world.
Responsible Nanotechnology Report Issued
CRN's quarterly Responsible Nanotechnology Report has been delivered to
members of the
C-R-Network. Interested parties from 19 nations on six different continents
received the report. Some of the countries include: Argentina, Australia,
Belgium, Czech Republic, Egypt, Finland, France, India, Iran, Ireland, Nigeria,
Russian Federation, Singapore, Taiwan, Thailand, and others, including the U.S.,
Canada, and the U.K.
If you would like to receive our quarterly report—in print, via email, or
both—just sign up for the
C-R-Network.
It's free, and we welcome everyone's participation.
Reminder about WFS Seminar & Conference
In connection with their hugely popular annual conference, the World Future
Society has announced "an exploration series designed to provide an outline of
several critical new fields with the potential for significant impact on the
social, economic, and cultural fabric of modern society." For this year, they
have organized a
Symposium on Nanotechnology (PDF), which CRN’s Mike Treder will assist in
presenting. It’s happening in Chicago on July 29, 2005. Hope to see you there!
Feature Essay: Molecular Manufacturing vs. Tiny
Nanobots
Chris Phoenix, Director of Research, Center for Responsible Nanotechnology
A few days ago, a high-ranking official of the National Nanotechnology
Initiative told me that statements against "nanobots" on their website had been
intended to argue against three-nanometer devices that could build anything.
This is frustrating, because no one has proposed such devices.
A three-nanometer cube would contain a few thousand atoms. This is about the
right size for a single component, such as a switch or gear. No one has
suggested building an entire robot in such a tiny volume. Even ribosomes, the
protein-constructing machinery of cells, are more like 30 nanometers. A
mechanical molecular fabrication system might be closer to 100 or 200
nanometers. That's still small enough to be built molecule-by-molecule in a few
seconds, but large enough to contain thousands or millions of components.
Nanosystems a few hundred nanometers in size are convenient for several other
reasons. They are small enough to be built error-free, and remain error-free for
months or years despite background radiation. They are large enough to be
handled mechanically with high efficiency and speed. They are smaller than a
human cell. They are large enough to contain a complete CPU or other useful
package of equipment. So it seems likely that designs for molecular
manufacturing products and nanofactories will be based on components of this
size.
So much for size. Let's look at the other half of that strawman, the part about
"could build anything." There has been a persistent idea that molecular
manufacturing proposes, and depends on, devices that can build any desired
molecule. In fact, such devices have never been proposed. The idea probably
comes from a misinterpretation of a section heading in Drexler's early book
Engines of Creation.
The
section in question talked about designing and building a variety of
special-purpose devices to build special molecular structures: "Able to tolerate
acid or vacuum, freezing or baking, depending on design, enzyme-like
second-generation machines will be able to use as 'tools' almost any of the
reactive molecules used by chemists -- but they will wield them with the
precision of programmed machines. They will be able to bond atoms together in
virtually any stable pattern, adding a few at a time to the surface of a
workpiece until a complex structure is complete. Think of such nanomachines as
assemblers."
Unfortunately, the section was titled "Universal Assemblers." This was misread
as referring to a single "universal" assembler, rather than a collective
capability of a large number of special-purpose machines. But there is not, and
never was, any proposal for a single universal assembler. The phrase has always
been plural.
The development of molecular manufacturing theory has in fact moved in the
opposite direction. Instead of planning for systems that can do a very broad
range of molecular fabrication, the latest designs aim to do just a few
reactions. This will make it easier to develop the reactions and analyze the
resulting structures.
Another persistent but incorrect idea that has attached itself to molecular
manufacturing is the concept of "disassemblers." According to popular belief,
tiny nanomachines will be able to take apart anything and turn it into raw
materials. In fact, disassemblers, as
described in Engines, have a far more mundane purpose: "Assemblers
will help engineers synthesize things; their relatives, disassemblers, will help
scientists and engineers analyze things." In other words, disassemblers are a
research tool, not a source of feedstock.
Without universal assemblers and disassemblers, molecular manufacturing is
actually pretty simple. Manufacturing systems built on a 100-nanometer scale
would convert simple molecular feedstock into machine parts with fairly simple
molecular structure—but, just as simple bricks can be used to build a wide
variety of buildings, the simple molecular structure could serve as a backbone
for rather intricate shapes. The manufacturing systems as well as their products
would be built out of modules a few hundred nanometers in size. These modules
would be fastened together to make large systems.
As I explained in my recent 50-page paper, "Molecular
Manufacturing: What, Why, and How," recent advances in theory have shown
that a planar layout for a nanofactory system can be scaled to any size,
producing about a kilogram per square meter per hour. Since the factory would
weigh about a kilogram per square meter, and could build a larger factory by
extruding it edgewise, manufacturing capacity can be doubled and redoubled as
often as desired. The implications of non-scarce and portable manufacturing
capacity, as well as the high performance, rapid fabrication, and low cost of
the products, are far beyond the scope of this essay. In fact, studying and
preparing for these implications is the reason that CRN exists.
* * * * * * * * * * * * * * *
CRN NEEDS YOUR HELP!
Since our founding two years ago, the
Center for Responsible
Nanotechnology has accomplished a great deal. We have published research
papers, spoken at conferences, sent out press releases, and created a sizable
presence on the web. As a result of these efforts, we have seen a considerable
increase in awareness of the implications of advanced nanotechnology. This is
vital work that few others are doing, despite its critical importance.
Unfortunately, we’re near the end of our current funding stream and virtually
operating out of our own pockets. Unless we can quickly raise the funds
necessary to support our growth, CRN's work will be severely hindered. If we are
to continue, we need to aggressively seek other sources of funding, and that
includes contributions from committed individuals such as yourself.
Please consider making a generous contribution to CRN. Your help, in any amount,
will make a real difference to us in building the organization and continuing to
inspire meaningful dialogue about our future in a world where
molecular manufacturing
is a reality.
To make a tax-deductible contribution by credit card, please
click here.
OR…you can mail a check, made out to "CRN/World Care" and addressed to:
CRN/World Care
PO Box 64001
Tucson, AZ 85728
Many thanks in advance for all the help you can give! Please
feel free to
contact us if you have any questions.
We sincerely appreciate the people who already have
donated. You are truly making the world a better and safer place.
* * * * * * * * * * * * * * *
C-R-Newsletter #29 April 14, 2005
New Research on DNA
Molecular Manufacturing, Step by
Step
Nanotech High Beams
Information Week
does CRN
Chris Phoenix Interviewed
Military Uses of
Nanotechnology
CRN goes to San Diego
CRN goes to Minneapolis
Feature Essay: Protein Springs
and Tattoo Needles—Work in progress at CRN
CRN Needs Your Help!
=========
It's been an extraordinarily busy and exciting month for CRN.
We'll recap most of the highlights here—but to keep up with us on a daily basis,
be sure to check our
Responsible Nanotechnology weblog.
New Research on DNA
Inspired by one of CRN's
Thirty Essential Studies —
Study #10, "What will be
required to develop nucleic acid manufacturing and products?" — researcher Frank
Boehm wrote "An Investigation of Nucleic Acid/DNA-Based Manufacturing." In a
26-page paper with 242 references,
published online this month at the Wise-Nano.org website, Boehm
describes many different kinds of tools in the DNA device toolbox, and shows how
rapidly development is occurring in this field.
Molecular Manufacturing, Step by Step
Advanced nanotechnology—molecular manufacturing—will bring
benefits and risks, both on an unprecedented scale. A
new paper by Chris
Phoenix, CRN's
Director of Research, suggests that development of molecular manufacturing
can be an incremental process from today's capabilities, and may not be as
distant as many believe.
Three stages for the development of molecular manufacturing, each with specific
milestones, are identified in the paper. The first stage is the
computer-controlled fabrication of precise molecular structures. The second
stage uses nanoscale tools to build more tools, enabling exponential growth of
the manufacturing base. The third stage, which integrates nanoscale products
into large structures, leads directly to desktop "nanofactories"
that could build advanced products.
Nanotech High Beams
It’s as if we’re driving very fast, into pitch-black darkness, moving rapidly
into uncharted territory… That's the state of nanotechnology today, argues
CRN Executive Director
Mike Treder
in
an essay published this month by Future Brief. The world's current
lack of preparedness for the disruptive consequences of molecular manufacturing
can only be redressed if we turn on the "high beams" and look further ahead.
Examining the health and safety risks of current nanoscale technologies is
necessary, but it is hardly sufficient.
Information Week does CRN
In March, Information Week published a
news article about the "desktop nanofabrication system" (nanofactory)
proposed by CRN's Chris Phoenix. The author, Chappell Brown, appropriately
distinguished between the
original vision of nanotechnology, and the relatively mundane—although
highly useful—work being carried out today. The same story also appeared in
EE Times. As a result of Brown's article, CRN's daily web traffic almost
doubled.
Chris Phoenix Interviewed
In an
in-depth interview published last month by nanomagazine, Chris
answered many questions regarding
nanofactory
feasibility and the
challenges that remain to develop the technology. This was actually the
second segment of a long two-part interview; the first part is
here. Thanks go to Sander Olson for his insightful questions and for
publishing the full interview.
Military Uses of Nanotechnology
The final results of a six-month long study conducted by the people who run the
Millennium Project of the American Council for the United Nations University
were published last month. Two topics were covered: "Potential Environmental
Pollution and Health Hazards Resulting from Possible Military Uses of
Nanotechnology," and "Implications for Research Priorities Helpful to Prevent
and/or Reduce Such Pollution and Hazards." An expert panel of 29
participants—including representation from CRN—identified potential military
uses of nanotechnology that might occur between 2005–2010 and 2010–2025, and
suggested research questions whose answers might produce knowledge to help
prevent or reduce the health and environmental hazards. More details on the
survey are available
here.
CRN goes to San Diego
Mike was invited to make a presentation during a special "Nanotechnology and the
Environment" symposium held in San Diego last month during the annual meeting of
the
American Chemical Society. Other speakers on the program were John Balbus of
Environmental Defense, Christine Peterson of the
Foresight Institute, and Alexis Vlandas of the
International Network of Scientists and Engineers for Global Responsibility.
The session was expertly organized by Barbara Karn and Nora Savage of the U.S.
Environmental Protection Agency. A large audience seemed genuinely
interested in what was presented and asked numerous questions about the
longer-term implications of
molecular manufacturing.
CRN goes to Minneapolis
Chris is scheduled to give a presentation next month at a
conference sponsored by the Society of Manufacturing Engineers (SME). His
talk, "Molecular Manufacturing: Beyond Nanomanufacturing," is based on a 50-page
paper he has written especially for this conference, and which will be published
in the official journal of conference proceedings. The one-day conference is
called "Molecular Nanotechnology and Manufacturing: The Enabling Tools and
Applications," and will take place at the Minneapolis Convention Center on May
4.
Feature Essay: Protein Springs and Tattoo Needles—Work in progress at CRN
Chris Phoenix, Director of Research, Center for Responsible Nanotechnology
This month's science essay will be a little different. Rather than explaining
how a known aspect of the nanoscale works, I'll provide a description of my
recent research activities and scientific thinking. I'll explain what the ideas
are, where the inspirations came from, and what they might mean. This is a view
"behind the scenes" of CRN. As always, I welcome comments and questions.
=========
I'm currently investigating two topics. One is how to make the simplest possible
nanoscale molecular manufacturing system. I think I've devised a version that
can be developed with today's technology, but can be improved incrementally to
approach the tabletop diamondoid nanofactory that is the major milestone of
molecular manufacturing. The other topic is how proteins work. I think I've had
an insight that solves a major mystery: how protein machines can be so
efficient. And if I'm right, it means that natural protein machines have
inherent performance limitations relative to artificial machines.
I'll talk about the proteins first. Natural proteins can do things that we can't
yet even begin to design into artificial proteins. And although we can imagine
and even design machines that do equivalent functions using other materials, we
can't build them yet. Although I personally don't expect proteins to be on the
critical path to molecular manufacturing, some very smart people do, both within
and outside the molecular manufacturing community. And in any case, I want to
know how everything at the nanoscale works.
One of the major questions about protein machines is how they can be so
efficient. Some of them, like ATP synthase, are nearly 100% efficient. ATP
synthase has a fairly complex job: it has to move protons through a membrane,
while simultaneously converting molecules of ADP to ATP. That's a pump and an
enzyme-style chemical reaction--very different kinds of operation--linked
together through a knobby floppy molecule, yet the system wastes almost no
energy as it transfers forces and manipulates chemicals. A puzzle, to be sure:
how can something like a twisted-up necklace of different-sized soft rubber
balls be the building material for a highly sophisticated machine?
I've been thinking about that in the back of my mind for a few months. I do that
a lot: file some interesting problem, and wait for some other random idea to
come along and provide a seed of insight. This time, it worked. I have been
thinking recently about entropy and springiness, and I've also been thinking
about what makes a nanoscale machine efficient. And suddenly it all came
together.
A nanoscale machine is efficient if its energy is balanced at each point in its
action. In other words, if a motion is "downhill" (the machine has less energy
at the end of the motion) then that energy must be transferred to something that
can store it, or else it will be lost as heat. If a motion is "uphill" (requires
energy) then that energy must be supplied from outside the machine. So a machine
with large uphills and downhills in its energy-vs.-position trajectory will
require a lot of power for the uphills, and will waste it on the downhills. A
machine with sufficiently small uphills and downhills can be moved back and
forth by random thermal motion, and in fact, many protein machines are moved
this way.
A month or so ago, I read an article on ATP synthase in which the researchers
claimed that the force must be constant over the trajectory, or the machine
couldn't be efficient. I thought about it until I realized why this was true. So
the question to be answered was, how was the force so perfectly balanced? I knew
that proteins wiggled and rearranged quite a bit as they worked. How could such
a seemingly ad-hoc system be perfectly balanced at each point along its
trajectory?
As I said, I have been thinking recently about entropic springs. Entropy, in
this application, means that nanoscale objects (including molecular fragments)
like to have freedom to wiggle. A stringy molecule that is stretched straight
will not be able to wiggle. Conversely, given some slack, the molecule will coil
and twist. The more slack it has, the more different ways it can twist, and the
happier it will be. Constraining these entropic wiggles, by stretching a string
or squashing a blob, costs energy. At the molecular scale, this effect is large;
it turns out that entropic springiness, and not covalent bond forces, is the
main reason why latex rubber is springy. This means that any nanoscale wiggly
thing can function as an entropic spring. I sometimes picture it as a tumbleweed
with springy branches--except that there is only one object (for example, a
stringy molecule) that wiggles randomly into all the different branch positions.
Sometimes I compare it to a springy cotton ball.
One Saturday morning I happened to be thinking simultaneously about writhing
proteins, entropic springs, and efficient machines. I suddenly realized, as I
thought about the innards of a protein rearranging themselves like a nest of
snakes, that installing lots of entropic springs in the middle of that complex
environment would provide lots of adjustable parameters to balance whatever
force the machine's function generated. Because of the complex structural
rearrangement of the protein, each spring would affect a different fraction of
the range of motion. Any uphills and downhills in its energy could be smoothed
out.
Natural protein machines are covered and filled with floppy bits that have no
obvious structural purpose. However, each of those bits is an entropic spring.
As the machine twists and deforms, its various springs are compressed or allowed
to expand. An entropic spring only has to be attached at one point; it will
press against any surface that happens to come into its range. Compressing the
spring takes energy and requires force; releasing the spring will recover the
energy, driving the machine forward.
As soon as I had that picture, I realized that each entropic spring could be
changed independently, by blind evolution. By simply changing the size of the
molecule, its springiness would be modified. If a change in a spring increased
the efficiency of the machine, it would be kept. The interior reconfiguration of
proteins would provide plenty of different environments for the springs--plenty
of different variables for evolution to tweak.
Always before, when I had thought about trying to design a protein for
efficiency and effectiveness, I had thought about its backbone--the molecular
chain that folds up to form the structure. This is large, clumsy, and soft--not
suitable for implementing subtle energy balancing. It would be very hard (no pun
intended) to design a system of trusses, using protein backbones and their
folded structure, that could implement the right stiffness and springiness to
balance the energy in a complex trajectory. But the protein's backbone has lots
of dangling bits attached. The realization that each of those was an entropic
spring, and each could be individually tuned to adjust the protein's energy at a
different position, made the design task suddenly seem easy.
The task could be approached as: 1) Build a structure to perform the protein's
function without worrying about efficiency and energy balance. Make it a large
structure with a fair amount of internal reconfiguration (different parts having
different relative orientations at different points in the machine's motion); 2)
Attach lots of entropic springs all over the structure; 3) Tune the springs by
trial and error until the machine is efficient--until the energy stored by
pressure on the myriad springs exactly balances the energy fluctuations that
result from the machine's functioning.
I proposed this idea to a couple of expert nanoscale scientists--a molecular
manufacturing theorist and a physicist. And I learned a lot. One of the experts
said that he had not previously seen the observation that adding lots of springs
made it easier to fine-tune the energy accurately. That was pretty exciting. I
learned that proteins do not usually disfigure themselves wildly during their
operation--interior parts usually just slip past each other a bit. I watched
some movies of proteins in action, and saw that they still seemed to have enough
internal structural variation to cause different springs to affect different
regions of the motion trajectory. So, that part of the idea still seems right.
I had originally been thinking in terms of the need to balance forces; I learned
that energy is a slightly more general way to think about the problem. But in
systems like these, force is a simple function of energy, and my theory
translated perfectly well into a viewpoint in terms of energy. It turned out
that one of my experts had studied genetic algorithms, and he warned that there
is no benefit to increasing the number of evolvable variables in the system if
the number of constraints increases by the same number. I hadn't expected that,
and it will take more theoretical work to verify that adding extra structures in
order to stick more entropic springs on them is not a zero-sum game. But my
preliminary thinking says that one piece of structure can have lots of springs,
so adding extra structures is still a win.
The other expert, the physicist, asked me how much of the effect comes from
entropic springiness vs. mechanical springiness. That's a very good question. I
realized that there is a measurable difference between entropic springs and
mechanical (covalent bond) springs: the energy stored by an entropic spring is
directly proportional to the temperature. If a machine's efficiency depends on
fine-tuning of entropic springs, then changing the temperature should change all
the spring constants and destroy the delicate energy balance that makes it
efficient. I made the prediction, therefore, that protein machines would have a
narrow temperature range in which they would be efficient. Then I thought a bit
more and modified this. A machine could use a big entropic spring as a
thermostat, forcing itself into different internal configurations at each
temperature, and fine-tuning each configuration separately. This means that a
machine with temperature-sensitive springs could evolve to be insensitive to
temperature. But a machine that evolved at a constant temperature, without this
evolutionary pressure, should be quite sensitive to temperature.
After thinking this through, I did a quick web search for the effect of
temperature on protein activity. I quickly found
a page containing a sketch of enzyme activity vs. temperature for various
enzymes. Guess what--the enzyme representing Arctic shrimp has maximum activity
around 4 C, and mostly stops working just a few degrees higher. That looks like
confirmation of my theory.
That web page, as well as another one, says that enzymes stop working at
elevated temperatures due to denaturation--change in three-dimensional
structure brought on by breaking of weak bonds in the protein. The
other web page also asserts that the rate of enzyme activity, "like all
reactions," is governed by the Arrhenius equation, at least up to the point
where the enzyme starts to denature. The Arrhenius equation says that if an
action requires thermal motion to jump across an energy barrier, the rate of the
action increases as a simple exponential function of temperature. But this
assumes that the height of the barrier is not dependent on temperature. If the
maintenance of a constant energy level (low barriers) over the range of the
enzyme's motion requires finely tuned, temperature dependent mechanisms, then
spoiling the tuning--by a temperature change in either direction--will decrease
the enzyme's rate.
I'll go out on a limb and make a testable prediction. I predict that many
enzymes that are evolved for operation in constant or nearly constant
temperature will have rapid decrease of activity at higher and lower
temperatures, even without structural changes. When the physical structure of
some of these supposedly denatured enzymes is examined, it will be found that
the enzyme is not in fact denatured: its physical structure will be largely
unchanged. What will be changed is the springiness of its entropic springs.
If I am right about this, there are several consequences. First, it appears that
the design of efficient protein machines may be easier than is currently
believed. There's no need to design a finely-tuned structure (backbone). Design
a structure that barely works, fill it with entropic springs, and fine-tune the
springs by simple evolution. Analysis of existing proteins may also become
easier. The Arrhenius equation should not apply to a protein that uses entropic
springs for energy balancing. If Arrhenius is being misapplied, then permission
to stop using it and fudging numbers to fit around it should make protein
function easier to analyze. (The fact that 'everyone knows' Arrhenius applies
indicates that, if I am right about entropic springs being used to balance
energy, I've probably discovered something new.)
Second, it may imply that much of the size and intricate reconfiguration of
protein machines exists simply to provide space for enough entropic springs to
allow evolutionary fine-tuning of the system. An engineered system made of stiff
materials could perform an equivalent function with equivalent efficiency by
using a much simpler method of force/energy compensation. For example, linking
an unbalanced system to an engineered cam that moves relative to a mechanical
spring will work just fine. The compression of the spring, and the height of the
cam, will correspond directly to the energy being stored, so the energy required
to balance the machine will directly specify the physical parameters of the cam.
The third consequence, if it turns out that protein machines depend on entropic
springs, is that their speed will be limited. To be properly springy, an
entropic spring has to equalize with its space; it has to have time to spread
out and explore its range of motion. If the machine is moved too quickly, its
springs will lose their springiness and will no longer compensate for the
forces; the machine will become rapidly less efficient. Stiff mechanical
springs, having fewer low-frequency degrees of freedom, can equilibrate much
faster. If I understand correctly, my physics expert says that a typical small
entropic spring can equilibrate in fractions of a microsecond. But stiff
mechanical nanoscale springs can equilibrate in fractions of a nanosecond.
I will continue researching this. If my idea turns out to be wrong, then I will
post a correction notice in our newsletter archive at the top of this article,
and a retraction in the next newsletter. But if my idea is right, then it
appears that natural protein machines must have substantially lower speeds than
engineered nanoscale machines can achieve with the same efficiency. "Soft" and
"hard" machines do indeed work differently, and the "hard" machines are simply
better.
=========
The second thing I am investigating is the design of a nanoscale molecular
manufacturing system that is simple enough to be developed today, but functional
enough to build rapidly improving versions and large-throughput arrays.
It may seem odd, given the ominous things CRN has said about the
dangers of advanced
molecular manufacturing, that I am working on something that could accelerate
it. But there's a method to my madness. Our overall goal is not to retard
molecular manufacturing; rather, it is to maximize the amount of thought and
preparation that is done before it is developed. Currently, many people
think molecular manufacturing is impossible, or at least extremely difficult,
and will not even start being developed for many years. But we believe that this
is not true--we’re concerned that a small group of smart people could figure out
ways to develop basic
capabilities fairly quickly.
The primary insights of molecular manufacturing--that stiff molecules make good
building blocks, that nanoscale machines can have extremely high performance,
and that general-purpose manufacturing enables rapid development of better
manufacturing systems--have been published for decades. Once even a few people
understand what can be done with even basic capabilities, we think they will
start working to develop them. If most people do not understand the
implications, they will be unprepared. By developing and publishing ways to
develop molecular manufacturing more easily, I may hasten its development, but I
also expect to improve general awareness that such development is possible and
may happen surprisingly
soon. This is a necessary precondition for
preparedness. That's why
I spend a lot of my time trying to identify ways to develop molecular
manufacturing more easily.
An early goal of molecular manufacturing is to build a nanoscale machine that
can be used to build more copies and better versions. This would answer nagging
worries about the ability of molecular manufacturing systems to make large
amounts of product, and would also enable rapid development of molecular
manufacturing technologies leading to advanced nanofactories.
I've been looking for ways to simplify the Burch/Drexler
planar assembly nanofactory. This method of "working backward" can be useful
for planning a development pathway. If you set a plausible goal pretty far out,
and then break it down into simpler steps until you get to something you can do
today, then the sequence of plans forms a roadmap for how to get from today's
capabilities to the end goal.
The first simplification I thought of was to have the factory place blocks that
were built externally, rather than requiring it to manufacture the blocks
internally. If the blocks can be prefabricated, then all the factory has to do
is grab them and place them into the product in specified locations.
I went looking for ways to join prefabricated molecular blocks and found a
possible solution. A couple of amino acids, cysteine and histidine, like to bind
to zinc. If two of them are hooked to each block, with a zinc ion in the middle,
they'll form a bond quite a bit stronger than a hydrogen bond. That seems
useful, as long as you can keep the blocks from joining prematurely into a
random lump. But you can do that simply by keeping zinc away.
So, mix up a feedstock with lots of molecular zinc-binding building blocks, but
no zinc. Build a smart membrane with precisely spaced actuators in it that can
transport blocks through the membrane. On one side of the membrane, put the
feedstock solution. On the other side of the membrane, put a solution of zinc,
and the product. As the blocks come through the membrane one at a time, they
join up with the zinc and become "sticky"--but the mechanism can be used to
retain them and force them into the right place in the product. It shouldn't
require a very complex mechanism to "grab" blocks from feedstock (via Brownian
assembly) through a hole in a membrane, move them a few nanometers to face the
product, and stick them in place. In fact, it should be possible to do this with
just one molecular actuator per position. A larger actuator can be used to move
the whole network around.
Then I thought back to some stuff I knew about how to keep blocks from clumping
together in solution. If you put a charge on the blocks, they will attract a
"screen" of counterions, and will not easily bump each other. So, it might be
possible to keep blocks apart even if they would stick if they ever bumped into
each other. In fact, it might be very simple. A zinc-binding attachment has four
amino acids per zinc, two on each side. Zinc has a +2 charge. If the rest of the
block has a -1 charge for every pair of amino acids, then when the block is
bound with zinc into a product, all the charges will match up. But if it's
floating in solution with zinc, then the zinc will still be attracted to the two
amino acids; in this case, the block should have a positive charge, since each
block will have twice as much zinc-charge associated with it in solution as when
it's fastened into the product. This might be enough to keep blocks from getting
close enough to bind together. But if blocks were physically pushed together,
then the extra zinc would be squeezed out, and the blocks would bind into a very
stable structure.
That's the theory, at this point. It implies that you don't need a membrane,
just something like a tattoo needle that attaches blocks from solution and
physically pushes them into the product. I do not know yet whether this will
work. I will be proposing to investigate this as part of a Phase 2 NIAC project.
If the theory doesn't work, there are several other ways to fasten blocks, some
triggered by light, some by pressure, and some simply by being held in place for
a long enough period of time.
It appears, then, that the simplest way to build a molecular manufacturing
system may be to develop a set of molecular blocks that will float separately in
solution but fasten together when pushed. At first, use a single kind of block,
containing a fluorescent particle. Use a scanning probe microscope to push the
blocks together. (You can scan the structure with the scanning probe microscope,
or see the cluster of fluorescence with an ordinary light microscope.) Once you
can build structures this way, build a structure that will perform the same
function of grabbing blocks and holding them to be pushed into a product. Attach
that structure to a nano-manipulator and use it to build more structures. You'd
have a hard time finding the second-level structures with a scanning probe
microscope, but again the cluster of fluorescence should show up just fine in a
light microscope.
Once you know you can build a passive structure that builds structures when
poked at a surface, the next step is to build an active structure--including an
externally controlled nanoscale actuator--that builds structures. Use your
scanning probe microscope with multiple block types to build an actuator that
pushes its block forward. Build several of those in an array. Let them be
controlled independently. You still need a large manipulator to move the array
over the surface, but you can already start to increase your manufacturing
throughput. By designing new block types, and new patterns of attaching the
blocks together, better construction machines could be built. Sensors could be
added to detect whether a block has been placed correctly. Nanoscale digital
logic could be added to reduce the number of wires required to control the
system. And if anyone can get this far, there should be no shortage of ideas and
interest directed at getting farther.
=========
That's an inside look at how my thinking process works, how I develop ideas and
check them with other experts, and how what I'm working on fits in with CRN's
vision and mission.
Please
contact me if you have any feedback.
Chris
* * * * * * * * * * * * * * *
CRN NEEDS YOUR HELP!
Since our founding two years ago, the
Center for Responsible
Nanotechnology has accomplished a great deal. We have published research
papers, spoken at conferences, sent out press releases, and created a sizable
presence on the web. As a result of these efforts, we have seen a considerable
increase in awareness of the implications of advanced nanotechnology. This is
vital work that few others are doing, despite its critical importance.
Unfortunately, we’re near the end of our current funding stream and virtually
operating out of our own pockets. Unless we can quickly raise the funds
necessary to support our growth, CRN's work will be severely hindered. If we are
to continue, we need to aggressively seek other sources of funding, and that
includes contributions from committed individuals such as you.
Please consider making a generous contribution to CRN. Your help, in any amount,
will make a real difference to us in building the organization and continuing to
inspire meaningful dialogue about our future in a world where
molecular manufacturing
is a reality.
To make a tax-deductible contribution by credit card, please
click here.
You will be directed to World Care's page
under "Network for Good." In the Designation box, be sure to say that your
donation is for CRN.
OR…you can mail a check, made out to "CRN/World Care" and addressed to:
CRN/World Care
PO Box 64001
Tucson, AZ 85728
Many thanks in advance for all the help you can give! Please
feel free to
contact us if you have any questions.
* * * * * * * * * * * * * * *
C-R-Newsletter #28 March 10, 2005
CONTENTS
CRN
goes to Washington
CRN goes to Italy
SciDev.net addresses
Nanotechnology
UK Government responds to Royal
Society
CRN says "Nanobots Not
Needed"
Talking with Economists
about Nanotechnology
Talking with Chemists about
Nanotechnology
Feature Essay:
Information Delivery for Nanoscale Construction
=========
CRN goes to Washington
Last month (February 10-11), Chris Phoenix attended a
two-day workshop in Washington D.C. organized by the U.S.
National Academy of Sciences, and spoke on a panel of experts about the
meaning of and potential for molecular manufacturing. Chris also was asked to
prepare a series of
briefing papers for the NAS committee, which have since been posted on our
Responsible Nanotechnology weblog. The committee appeared to study the matter
with an open mind, and we look forward to their first report to Congress
this summer.
CRN goes to Italy
While Chris was in Washington, Mike Treder was in Trieste,
Italy, taking part in an
Expert Group Meeting on "North-South Dialog on Nanotechnology: Challenges
and Opportunities." The meeting was organized by the
International Centre for Science and High Technology, an Institute of the
United Nations operating in the framework of the
United Nations Industrial Development Organization.
A total of eighty people from all around the world—scientists, academics,
government personnel, and NGO representatives—were gathered for this event. Mike
presented his ideas on "Creating Effective Public Policy for Managing Advanced
Nanotechnology," which was favorably received, although there were differing
points of view on the
expected time frame for development of molecular manufacturing. You can view
Mike's PowerPoint presentation
here.
SciDev.net addresses Nanotechnology
The online news site SciDev.net recently posted a "Nanotechnology
Quick Guide," which includes an overview of both current nanoscale
technologies and the possibilities of advanced nanotechnology. One of the
links they provide is to CRN, and in fact, we were told by the Quick Guide’s
primary author, Catherine Brahic, that she used our material as a resource for
her writing.
SciDev.net also published
an editorial entitled "Helping the poor: the real challenge of nanotech,"
commenting on the issues discussed at the Expert Group Meeting mentioned
above.
UK Government responds to Royal Society
In 2003, the British government asked the
Royal Society (somewhat equivalent to the U.S. National Academy of Sciences)
to undertake a study on "nanotechnology and the health and safety,
environmental, ethical and social issues that might stem from it." Their
final report was issued on July 29, 2004.
The UK government finally got around to responding to the report’s findings just
a few weeks ago, and no one, it seems, was pleased with
what they said. Professor Ann Dowling, chair of the working group that
produced the report,
expressed disappointment, as did scientist and blogger
Richard Jones, and eco-activist
Jim Thomas of the ETC Group. CRN also
spoke out about the government’s tepid response and the urgent need for more
serious consideration of
both the risks and benefits of nanotechnology.
CRN says "Nanobots Not Needed"
The popular idea of so-called nanobots, powerful and at risk of running wild, is
not part of modern plans for building things "atom-by-atom" by molecular
manufacturing. Studies indicate that most people don't know the difference
between molecular manufacturing, nanoscale technology, and nanobots. Confusion
about terms, fueled by science fiction, has distorted the truth about advanced
nanotechnology. Nanobots are not needed for manufacturing, but continued
misunderstanding may hinder research into highly beneficial technologies and
discussion of the real dangers.
That's the summary of a new
briefing document
prepared by CRN and provided primarily for journalists and others who write or
teach about nanotechnology.
As nanoscale technologies begin to move from the lab to the marketplace, and
attention turns to
molecular manufacturing research, it will be increasingly important to
counter outdated and incorrect ideas of nanotechnology and molecular
manufacturing. Both scientists and the public have gotten the idea that
molecular manufacturing requires the use of nanobots, and they may criticize or
fear it on that basis. The truth is less sensational, but
its implications are
equally compelling.
Our statement stimulated lively discussion on the Foresight Institute's
nanodot site,
Howard Lovy's blog, and the Google group
sci.nanotech.
Talking with Economists about
Nanotechnology
Mike was asked to serve as moderator for a
panel discussion at the
Eastern Economic Association Annual Conference in New York City last week.
The panel was on "The Inevitability of BIG in a Robotic Future" (BIG is Basic
Income Guarantee). During discussion after the panelist's presentations, the
subject of economic disruption and other societal impacts resulting from
molecular manufacturing was raised. So Mike had the opportunity to share some of
CRN's concerns with a group of noted economists and sociologists.
Talking with Chemists about
Nanotechnology
We received a last-minute invitation to speak at a "Nanotechnology and the
Environment" symposium during the
American Chemical Society's 2005 annual meeting. Mike will travel to San
Diego, California, this weekend to deliver a short presentation on "the
environmental, human health and societal aspects of nanotechnology." It won't be
easy to adequately cover so many issues in a short address, but it's good to see
that the ACS is taking our point of view seriously.
Feature Essay: Information
Delivery for Nanoscale Construction
Chris Phoenix, Director of Research, CRN
A widely acknowledged goal of
nanotechnology is to build intricate, useful nanoscale structures. What
usually goes unstated is how the structures will be specified. Simple structures
can be created easily: a crystal is an atomically precise structure that can be
created from simple molecules and conditions. But complex nano-products will
require some way to deliver large quantities of information to the nanoscale.
A key indicator of a technology's usefulness is how fast it can deliver
information. A kilobyte is not very much information—less than a page of text or
a thumbnail image. A dialup modem connection can transfer several kilobytes per
second. Today's nanoscale manufacturing techniques can transfer at most a few
kilobytes per second. This will not be enough to make advanced products—only
simple materials or specialized components.
The amount of information needed to specify a product is not directly related to
the size of the product. A product containing repetitive structures only needs
enough information to specify one of the structures and control the placement of
the rest. The amount of information that needs to be delivered also depends on
whether the receiving machine must receive an individual instruction for every
operation, or whether it can carry out a sequence of operations based on stored
instructions. Thus, a primitive fabrication system may require a gigabyte of
information to place a million atoms, while a gigabyte may be sufficient to
specify a fairly simple kilogram-scale product built with an advanced
nanofactory.
There are several ways to deliver information to the nanoscale so as to
construct things. Information can either be encoded materially, in a stable
pattern of atoms or electrons, or it can be in an ephemeral form such as an
electric field, a pattern of light, a beam of charged particles, the position of
a scanning probe, or an environmental condition like temperature. The goal of
manufacturing is to embody the information, however it is delivered, into a
material product. As we will see, different forms of delivery have different
advantages and limitations.
Today's Techniques
To create a material pattern, it is tempting to start with materially encoded
information. This is what self-assembly does. A molecule can be made so that it
folds on itself or joins with others in quite intricate patterns. An example of
this that is well understood, and has already been used to make nanoscale
machines, is DNA. (See our previous science essay, "Nucleic
Acid Engineering.") Biology uses DNA mainly to store information, but in the
lab it has been used to make polyhedra, grid structures, and even a programmable
machine that can synthesize DNA strands.
One problem with self-assembly is that all the information in the final
structure must be encoded in the components. In order to make a complicated
structure, a lot of information must be programmed into the component molecules.
There are only a few ways to get information into molecules. One is to make the
molecules a piece at a time. In a long linear chain like DNA, this can be done
by repeating a few operations many times—specifically, by changing the chemical
environment in a way that adds one selected block to the chain in each
operation. (This can be viewed either as chemistry or as manufacturing.)
Automated machines exist that will do this by cycling chemicals through a
reactor, but they are relatively slow, and the process is expensive. The
information rate can be greatly increased by controlling the process with light;
by shining light in programmed sequence on different regions of a surface, DNA
can be grown in many different patterns in parallel. This can create a large
“library” of different DNA molecules with programmed sequences.
Another problem with self-assembly is that when the building blocks are mixed
together, it is hard to impose long-range order and to build heterogeneous
engineered structures. This limitation may be partially alleviated by providing
a large-scale template, either a material structure or an ephemeral spatial
pattern. Adding building blocks in a programmed sequence rather than mixing them
all together all at once also may help. A combination of massively parallel
programmable molecule synthesis and templated or sequenced self-assembly may be
able to deliver kilobytes per second of information to the nanoscale.
A theoretical possibility should be mentioned here. Information can be created
by starting with a lot of random codes, throwing away all the ones that don't
work, and duplicating the ones that do. One problem with this is that for all
but the simplest criteria, it will be too difficult and time-consuming to
implement tests for the desired functionality. Another problem is that evolved
solutions will require extra work to characterize, and unless characterized,
they will be hard to integrate into engineered systems. Although evolution can
produce systems of great subtlety and complexity, it is probably not suitable
for producing easily characterized general-purpose functional modules. Specific
molecular bio-designs such as molecular motors may be worth characterizing and
using, but this will not help with the problem of controlling the construction
of large, heterogeneous, information-rich products.
Optical lithography of semiconductors now has the capability to generate
nanoscale structures. This technique creates a pattern of light using a mask.
The light causes chemical changes in a thin surface layer; these changes can
then be used to pattern a substrate by controlling the deposition or removal of
material. One drawback of this approach is that it is not atomically precise,
since the pattern of light is far too coarse to resolve individual atoms.
Another drawback is that the masks are pre-built in a slow and very expensive
process. A computer chip may embody billions of bytes of information, but the
masks may take weeks to make and use; again, this limits the data rate to
kilobytes per second. There has been recent talk of using MEMS (micro electro
mechanical systems) technology to build programmable masks; if this works out,
it could greatly increase the data rate.
Several tools can modify single points in serial fashion with atomic or
near-atomic resolution. These include scanning probe microscopes and beams of
charged particles. A scanning probe microscope uses a large but sensitive
positioning and feedback system to bring a nanoscale point into controlled
physical contact with the surface. Several thousand pixels can be imaged per
second, so in theory an automated system could deliver kilobytes per second of
changes to the surface. An electron beam or ion beam can be steered
electronically, so it can be relatively fast. But the beam is not as precise as
a scanning probe can be, and must work in vacuum. The beam can be used either to
remove material, to chemically transform it, or to deposit any of several
materials from low-pressure gas. It takes a fraction of a millisecond to make a
shallow feature at a chosen point. Again, the information delivery rate is
kilobytes per second.
Nanoscale Tools
To deliver information at a higher rate and use the information for more precise
construction, new technology will be required. In most of the techniques
surveyed above, the nanoscale matter is inert and is acted on by outside forces
(ephemeral information) created by large machines. In self-assembly, the
construction material itself encodes static patterns of information—which
probably were created by large machines doing chemistry. By contrast, nanoscale
tools, converting ephemeral information to concrete operations, could
substantially improve the delivery rate of information for nanoscale
construction. Large tools acting on inert nanoscale objects could never come
close to the data rates that are theoretically possible with nanoscale tools.
One reason why nanoscale tools are better is that they can move faster. To a
first approximation, the operating frequency of a tool increases in direct
proportion as its linear size shrinks. A 100-nm tool should be about a million
times faster than a 10-cm tool.
The next question is how the information will be delivered. There are several
candidates for really fast information delivery. Light can be switched on and
off very rapidly, but is difficult to focus tightly. Another problem is that
absorption of light is probabilistic, so a lot of light would have to be used
for reliable information delivery. Perhaps surprisingly, mechanical signals may
be useful; megahertz vibrations and pressure waves can be sent over useful
distances. Electrical signals can be sent along nanoscale wires so that multiple
independent signals could be delivered to each tool. In principle, the
mechanical and electrical portions of the system could be synchronized for high
efficiency.
Nanoscale computing elements can help with information handling in two ways.
First, they can split up a broadcast signal, allowing several machines receiving
the same signal to operate independently. This can reduce the complexity of the
macro-to-nano interface. Second, nanoscale computation can be used to implement
some kinds of error handling at a local level.
A final advantage of nanoscale tools, at least the subset of tools built from
molecules, is that they can be very precise. Precision is a serious problem in
micron-sized tools. A structure built by lithography looks like it has been
whittled with a pocket knife—the edges are quite ragged. This has made it very
difficult to build complex, useful mechanical devices at the micron scale using
lithography. Fortunately, things get precise again at the very bottom, because
atoms are discrete and identical. Small and simple molecular tools have been
built, and work is ongoing to build larger and more integrated systems. The
structural precision of molecular tools promises several advantages, including
predictable properties and low-friction interfaces.
Several approaches could be used, perhaps in combination, to build a nanoscale
fabrication system. If a simple and repetitive system can be useful, then
self-assembly might be used to build it. A repetitive system, once fabricated,
might be made less repetitive (programmed heterogeneously) by spatial patterns
such as an array of light. If it contains certain kinds of electronics, then
signals could be sent in to uniquely reconfigure the circuitry in each repeating
sub-pattern.
Of course, the point of the fabrication system is to build stuff, and a
particularly interesting kind of system is one that can build larger or better
fabrication systems. With information supplied from outside, a manufacturing
system of this sort could build a larger and more complex version of itself.
This approach is one of the goals of molecular manufacturing. It would allow the
first tiny system to be built by a very expensive or non-scalable method, and
then that tiny system can build larger ones, rapidly scaling upward and
drastically reducing cost. Or if the initial system was built by self-assembly,
then subsequent systems could be more complex than self-assembly could easily
achieve.
The design of even a tabletop general-purpose manufacturing system could be
relatively simple, heterogeneous but hierarchical and repetitive. Once the basic
capabilities of nanoscale actuation, computation, and fabrication are achieved
in a way that can be engineered and recombined, it may not take too long to
start developing nanoscale tools that can do this in parallel, using
computer-supplied blueprints to build larger manufacturing systems and a broad
range of products.
C-R-Newsletter #27 February 3, 2005
CONTENTS
NAS Workshop
Expert Group Meeting
Network Activity Coordinator
Events Coordinator
Nano-Workshops
Symposium on Nanotechnology
New Paper Posted
Feature Essay: What Is
Molecular Manufacturing?
=========
NAS Workshop
As part of the U.S.
21st Century Nanotechnology Research and Development Act (PDF), passed by
Congress and signed into law by the President in December 2003, the National
Academy of Sciences is required to "organize a workshop to study the technical
feasibility of molecular self-assembly for the manufacture of materials and
devices at the molecular scale."
That workshop is being held in Washington DC February 10-11, 2005. CRN’s Chris
Phoenix has been appointed to a panel of experts that will address the
NAS committee, and he will attend the entire workshop.
Expert Group Meeting
At the same time that Chris is in Washington, Mike Treder will be in Trieste,
Italy, to take part in an
Expert Group Meeting on "North-South dialog on nanotechnology: challenges
and opportunities." The meeting is organized by the
International Centre for Science and High Technology, an Institute of the
United Nations operating in the framework of the
United Nations Industrial Development Organization. This is quite an honor,
and we are pleased to have the opportunity to contribute.
Network Activity Coordinator
We are pleased to announce the appointment of Martin Coppa to the position of
CRN Network
Activity Coordinator. In this volunteer role, he will promote opportunities
for student research
collaborations within educational networks, maintain up-to-date records of
C-R-Network
membership, and coordinate communication with Network members.
Martin, who lives in San Francisco, is an undergraduate student majoring in
chemical engineering. Along with interests in the scientific development of
nanotechnology and specifically molecular manufacturing (MM), he is very
concerned with the socio-political developments that MM will set in motion. We
are excited about the energy and creativity that Martin will bring to his
activities with CRN. Congratulations, and welcome, Martin!
Events Coordinator
To educate, engage, and empower others to prepare for molecular manufacturing,
CRN is now offering two-day Nano-Workshops (see below). There may be a paid
position for someone to help us plan and coordinate these events, especially if
that person can identify and solicit prospective recipients of workshop
presentations. We’re also seeking additional
speaking engagements in
2005. Someone who can solicit such opportunities for CRN Principals and manage
our speaking and presentation calendar might occupy a part-time paid position,
either combined with or separate from managing our workshops. If you’re
interested, please contact Executive Director
Mike Treder.
Nano-Workshops
One of CRN’s
key activities for 2005 will be conducting on-site Nano-Workshops, designed
to educate interested groups of people about the impending impacts of molecular
manufacturing, to assess how it may affect them and their organizations, and to
guide them in deciding what they might do about it. We’ve developed the
curriculum, which covers: 1) Technical Background for Molecular Manufacturing;
2) Introduction to Implications; 3) Projections of Molecular Manufacturing
Development; and 4) Impact and Implications, with focus on the audience's
concerns. The workshops will be interactive, will include group brainstorming,
and will aim at forming a long-range action plan for the group to pursue.
Do you know of a company, a school, a nonprofit organization, or another group
that might be interested in learning about the future of nanotechnology and how
it could affect them? We’re laying out our calendar now, and the first three
groups to book a workshop will benefit from a significant discount—so please
encourage them to contact us
right away.
Symposium on Nanotechnology
In connection with their hugely popular
annual conference, the World Future Society has announced "an exploration
series designed to provide an outline of several critical new fields with the
potential for significant impact on the social, economic, and cultural fabric of
modern society." For this year, they have organized a
Symposium on Nanotechnology, which Mike Treder will assist in presenting.
It’s happening in Chicago on July 29, 2005.
New Paper Posted
The paper that Mike presented at the November 2004
International Congress of Nanotechnology, which is titled "Bridges to
Safety, and Bridges to Progress", has been
posted on our website.
Here’s the abstract: Advanced nanotechnology offers unprecedented
opportunities for progress—defeating poverty, starvation, and disease, opening
up outer space, and expanding human capacities. But it also brings unprecedented
risks—massive job displacement causing economic and social disruption, threats
to civil liberties from ubiquitous surveillance, and the specter of devastating
wars fought with far more powerful weapons of mass destruction. The challenge of
achieving the goals and managing the risks of nanotechnology requires more than
just brilliant molecular engineering. In addition to scientific and technical
ingenuity, other disciplines and talents will be vitally important. No single
approach will solve all problems or address all needs. The only answer is a
collective answer, and that will demand an unprecedented collaboration—a network
of leaders in business, government, academia, and NGOs. It will require
participation from people of many nations, cultures, languages, and belief
systems. Never before have we faced such a tremendous opportunity—and never
before have the risks been so great. We must begin building bridges that will
lead to safety and progress for the entire world; bridges that will develop
common understanding, create lines of communication, and create a stable
structure that will enable humankind to pass safely through the transition into
the nano era.
Feature Essay: What Is Molecular Manufacturing?
Chris Phoenix, Director of Research, CRN
The term "molecular manufacturing" has been associated with all sorts of
futuristic stuff, from bloodstream robots to
grey goo to tabletop
factories that can make a new factory in a few hours. This can make it hard for
people who want to understand the field to know exactly
what's being claimed and
studied. This essay explains what the term originally meant, why the
approach is thought to be powerful enough to create a field around, why so many
futuristic ideas are associated with it, and why some of those ideas are more
plausible than they may seem.
Original Definition
Eric Drexler defined the term "molecular manufacturing" in his 1992 technical
work Nanosystems.
His definition used some other terms that need to be considered first.
Mechanochemistry In this volume, the chemistry
of processes in which mechanical systems operating with atomic-scale precision
either guide, drive, or are driven by chemical transformations.
In other words, mechanochemistry is the direct, mechanical
control of molecular structure formation and manipulation to form atomically
precise products. (It can also mean the use of reactions to directly drive
mechanical systems—a process that can be nearly 100% efficient, since the energy
is never thermalized.) Mechanochemistry
has already been demonstrated:
Oyabu has used atomic force microscopes, acting purely mechanically, to
remove single silicon atoms from a covalent lattice and put them back in the
same spot.
Mechanosynthesis Chemical synthesis controlled
by mechanical systems operating with atomic-scale precision, enabling direct
positional selection of reaction sites; synthetic applications of
mechanochemistry. Suitable mechanical systems include AFM mechanisms,
molecular manipulators, and molecular mill systems.
In other words, mechanosynthesis is the use of mechanically
guided molecular reactions to build stuff. This does not require that every
reaction be directly controlled. Molecular building blocks might be produced by
ordinary chemistry; products might be strengthened after manufacture by
crosslinking; molecular manufactured components might be joined into products by
self-assembly; and building blocks similar to those used in self-assembly might
be guided into chosen locations and away from alternate possibilities. Drexler’s
definition continues:
Processes that fall outside the intended scope of this
definition include reactions guided by the incorporation of reactive moieties
into a shared covalent framework (i.e., conventional intramolecular
reactions), or by the binding of reagents to enzymes or enzyme-like catalysts.
The point of this is to exclude chemistry that happens by pure
self-assembly and cannot be controlled from outside. As we will see, external
control of the reactions is the key to successful molecular manufacturing. It is
also the main thing that distinguishes molecular manufacturing from other kinds
of nanotechnology.
The principle of mechanosynthesis—direct positional
control—can be useful with or without covalent bonding. Building blocks like
those used in self-assembly, held together by hydrogen bonding or other
non-covalent interactions, could also be joined under mechanical control. This
would give direct control of the patterns formed by assembly, rather than
requiring that the building blocks themselves encode the final structure and
implement the assembly process.
Molecular manufacturing The production of
complex structures via nonbiological mechanosynthesis (and subsequent assembly
operations).
There is some wiggle room here, because "complex structures"
is not defined. Joining two molecules to make one probably doesn't count. But
joining selected monomers to make a polymer chain that folds into a
predetermined shape probably does.
Machine-phase chemistry The chemistry of
systems in which all potentially reactive moieties follow controlled
trajectories (e.g., guided by molecular machines working in vacuum).
This definition reinforces the point that machine-phase
chemistry is a narrow subset of mechanochemistry. Mechanochemistry does not
require that all molecules be controlled; it only requires that reactions
between the molecules must be controlled. Mechanochemistry is quite compatible
with "wet" chemistry, as long as the reactants are chosen so that they will only
react in the desired locations. A ribosome appears to fit the requirement;
Drexler specified that molecular manufacturing be done by nonbiological
mechanosynthesis, because otherwise biology would be covered by the definition.
Although it has not been well explored, machine-phase chemistry has some
theoretical advantages that make it worth further study. But molecular
manufacturing does not depend on a workable machine-phase chemistry being
developed. Controversies about whether diamond can be built in vacuum do not
need to be settled in order to assess the usefulness of molecular manufacturing.
Extending Molecular Manufacturing
As explained in the first section, the core of molecular manufacturing is the
mechanical control of reactions so as to build complex structures. This simple
idea opens up a lot of possibilities at the nanoscale. Perhaps the three most
important capabilities are engineering, blueprint delivery, and the creation of
manufacturing tools. These capabilities reinforce each other, each facilitating
the others.
It is often thought that the nanoscale is intractably complex, impossible to
analyze. Nearly intractable complexity certainly can be found at the nanoscale,
for example in the prediction of protein folding. But not everything at the nanoscale is complex.
DNA folding, for example, is much simpler, and the engineering of folded
structures is now pretty straightforward. Crystals and self-assembled monolayers
also have simple aspects: they are more or less identical at a wide range of
positions. The mechanical properties of nanoscale structures change as they get
extremely small, but even single-nanometer covalent solids (diamond, alumina,
etc) can be said to have a well-defined shape.
The ability to carry out predictable synthesis reactions at chosen sites or in
chosen sequences should allow the construction of structures that are intricate
and functional, but not intractably complex. This kind of approach is a good fit
for engineering. If a structure is the wrong shape or stiffness, simply changing
the sequence of reactions used to build it will change its structure—and at
least some of its properties—in a predictable way.
It is not always easy to control things at the nanoscale. Most of our tools are
orders of magnitude larger, and more or less clumsy; it's like trying to handle
toothpicks with telephone poles. Despite this, a few techniques and approaches
have been developed that can handle individual molecules and atoms, and move
larger objects by fractions of nanometers. A separate approach is to handle huge
numbers of molecules at once, and set up the conditions just right so that they
all do the same thing, something predictable and useful. Chemistry is an example
of this; the formation of self-assembled monolayers is another example. The
trouble with all of these approaches is that they are limited in the amount of
information that can be delivered to the nanoscale. After a technique is used to
produce an intermediate product, a new technique must be applied to perform the
next step. Each of these steps is hard to develop. They also tend to be slow to
use, for two reasons: big tools move slowly, and switching between techniques
and tools can take a lot of time.
Molecular manufacturing has a big advantage over other nanoscale construction
techniques: it can usefully apply the same step over and over again. This is
because each step takes place at a selected location and with selected building
blocks. Moving to a different location, or selecting a different building block
from a predefined set, need not insert enough variation into the process to
count as a new step that must be developed and characterized separately.
A set of molecular manufacturing operations, once worked out, could be
recombined like letters of an alphabet to make a wide variety of predictable
products. (This benefit is enhanced because mechanically guided chemistry can
play useful games with reaction barriers to speed up reactions by many orders of
magnitude; this allows a wider range of reactants to be used, and can reduce the
probability of unwanted side reactions.) The use of computer-controlled tools
and computer-aided translation from structure to operation sequence should allow
blueprints to be delivered directly to the nanoscale.
Although it is not part of the original definition of molecular manufacturing,
the ability to build a class of product structures that includes
manufacturing the tools used to build them may be very useful. If the tools can be engineered
by the same skill set that produces useful products, then research and
development may be accelerated. If new versions of tools can be constructed and
put into service within the nanoscale workspace, that may be more efficient than
building new macro-scale tools each time a new design is to be tested. Finally,
if a set of tools can be used to build a second equivalent set of tools, then
scaleup becomes possible.
The idea of a tool that can build an improved copy of itself may seem
counterintuitive: how can something build something else that's more complex
than itself? But the inputs to the process include not just the structure of the
first tool, but the information used to control it. Because of the sequential,
repetitive nature of molecular manufacturing, the amount of information that can
be fed to the process is essentially unlimited. A tool of finite complexity,
controlled from the outside, can build things far more physically complex than
itself; the complexity is limited by the quality of the design. If engineering
can be applied, then the design can be quite complex indeed; computer chips are
being designed with a billion transistors.
From the mechanical engineering side, the idea of tools building tools may be
suspect because it seems like precision will be lost at each step. However, the
use of covalent chemistry restores precision. Covalent reactions are inherently
digital: in general, either a bond is formed which holds the atoms together, or
the bond is missing and the atoms repel each other. This means that as long as
the molecules can be manipulated with enough precision to form bonds in the
desired places, the product will be exactly as it was designed, with no loss of
precision whatsoever. The precision required to form bonds reliably is a
significant engineering requirement that will require careful design of tools,
but is far from being a showstopper.
Scaleup
The main limitation of molecular manufacturing is that molecules are so small.
Controlling one reaction at a time with a single tool will produce astonishingly
small masses of product. At first sight, it may appear that there is no way to
build anything useful with this approach. However, there is a way around this
problem, and it’s the same way used by ribosomes to build an elephant: use a lot
of them in parallel. Of course, this requires that the tools must be very small,
and it must be possible to build a lot of them and then control them all.
Engineering, direct blueprint injection, and the use of molecular manufacturing
tools to build more tools can be combined to achieve this.
The key question is: How rapidly can a molecular manufacturing tool create its
own mass of product? This value, which I'll call "relative productivity,"
depends on the mass of the tool; roughly speaking, its mass will be about the
cube of its size. For each factor of ten shrinkage, the mass of the tool will
decrease by 1,000. In addition, small things move faster than large things, and
the relationship is roughly linear. This means that each factor of ten shrinkage
of the tool will increase its relative productivity by 10,000 times; relative
productivity increases as the inverse fourth power of the size.
A typical scanning probe microscope might weigh two kilograms, have a size of
about 10 cm, and carry out ten automated operations per second. If each
operation deposits one carbon atom, which masses about 2x10-26 kg,
then it would take 1026 seconds or six billion billion years for that
scanning probe microscope to fabricate its own mass. But if the tool could be
shrunk by a factor of a million, to 100 nm, then its relative throughput would
increase by 1024, and it would take only 100 seconds to fabricate its
own mass. This assumes an operation speed of 10 million per second, which is
about ten times faster than the fastest known enzymes (carbonic anhydrase and
superoxide dismutase). But a relative productivity of 1,000 or even 10,000
seconds would be sufficient for a very worthwhile manufacturing technology. (An
inkjet printer takes about 10,000 seconds to print its weight in ink.) Also,
there is no requirement that a fabrication operation deposit only one atom at a
time; a variety of molecular fragments may be suitable.
To produce a gram of product will take on the order of a gram of nanoscale
tools. This means that huge numbers of the tools must be controlled in parallel:
information and power must be fed to each one. There are several possible ways
to do this, including light and pressure. If the tools can be fastened to a
framework, it may be easier to control them, especially if they can build the
framework and include nanoscale structures in it. This is the basic concept of a
nanofactory.
Nanofactories and Their Products
A nanofactory is (will be) an integrated manufacturing system containing large
numbers of nanoscale molecular manufacturing workstations (tool systems). This
appears to be the most efficient and engineerable way to make nanoscale
productive systems produce large products. With the workstations fastened down
in known positions, their nanoscale products can more easily be joined. Also,
power and control signals can be delivered through hardwired connections.
The only way to build a nanofactory is with another nanofactory. However, the
product of a nanofactory may be larger than itself; it does not appear
conceptually or practically difficult to build a small nanofactory with a single
molecular manufacturing tool, and build from there to a kilogram-scale
nanofactory. The architecture of a nanofactory must take several problems into
account, in addition to the design of the individual fabrication workstations.
The mass and organization of the mounting structure must be included in the
construction plans. A small fraction (but large number) of the nanoscale
equipment in the nanofactory will be damaged by background radiation, and the
control algorithms will have to compensate for this in making functional
products. To make heterogeneous products, the workstations and/or the
nanoproduct assembly apparatus must be individually controlled; this probably
requires control logic to be integrated into the nanofactory.
It may seem premature to be thinking about nanofactory design before the first
nanoscale molecular manufacturing system has been built. But it is important to
know what will be possible, and how difficult it will be, in order to estimate
the ultimate payoff of a technology and the time and effort required to achieve
it. If nanofactories were impossible, then molecular manufacturing would be
significantly less useful; it would be very difficult to make large products.
But preliminary studies seem to show that nanofactories are actually not very
difficult to design, at least in broad outline. I have written an
80-page paper that covers error handling, mass and layout, transport of
feedstock, control of fabricators, and assembly and design of products for a
very primitive nanofactory design. My best estimate is that this design could
produce a duplicate nanofactory in less than a day. Nanofactory designs have
been proposed that appear to be much more flexible in how the products are
formed, but they have not yet been worked out in as much detail.
If there is a straightforward path from molecular manufacturing to
nanofactories, then useful
products will not be far behind. The ability to specify every cubic
nanometer of an integrated kilogram product, filling the product with engineered
machinery, will at least allow the construction of extremely powerful computers.
If the construction material is strong, then mechanical performance may also be
extremely good; scaling laws predict that power density increases as the inverse
of machine size, and nanostructured materials may be able to take advantage of
almost the full theoretical strength of covalent bonds rather than being limited
by propagating defects.
Many products have been imagined for this technology. A few have been designed
in sufficient detail that they might work as claimed. Robert Freitas's
Nanomedicine Vol. I contains analyses of many kinds of nanoscale machinery.
However, this only scratches the surface. In the absence of more detailed
analysis identifying quantitative limits, there has been a tendency for
futurists to assume that nano-built products will achieve performance close to
the limits of physical law. Motors three to six orders of magnitude more
powerful than today's; computers six to nine orders of magnitude more compact
and efficient; materials at least two orders of magnitude stronger—all built by
manufacturing systems many orders of magnitude cheaper—it's not hard to see why
futurists would fall in love with this field, and skeptics would dismiss it. The
solution is threefold: 1) open-minded but quantitative investigation of the
theories and proposals that have already been made; 2) constructive attempts
to fill in missing details; and 3) critical efforts to identify unidentified
problems with the application of the theories.
Based on a decade and a half of study, I am satisfied that some kind of
nanofactory can be made to work efficiently enough to be more than competitive
with today's manufacturing systems, at least for some products. In addition, I
am satisfied that molecular manufacturing can be used to build simple,
high-performance nanoscale devices that can be combined into useful, gram-scale,
high-performance products via straightforward engineering design. This is enough
to make molecular manufacturing seem very interesting, well worth
further study; and in
the absence of evidence to the contrary, worth a measure of preliminary concern
over how some of its possible products might be used.
C-R-Newsletter #26 January 3, 2005
CONTENTS
Happy
Birthday to CRN!
X Prize Proposals
CRN Blog Highlights
Nano-Workshops
Staff Positions Available
Year in Review
Feature Essay: Advantages of
Engineered Nanosystems
=========
Happy Birthday to CRN!
In December 2002,
Chris Phoenix
and Mike Treder founded the Center for Responsible Nanotechnology. So, we've
just celebrated our second birthday. It's been an eventful two years, with a lot
learned and, we think, a lot accomplished. Many thanks to all of you who have
contributed your time, your advice, your financial support, and your interest in
our work. We're looking forward to another great year in 2005.
X Prize Proposals
The
X Prize people—who inspired SpaceShipOne—are at it again, and this time
they're interested in molecular manufacturing (among other things). CRN is
suggesting a prize proposal to encourage the development of a primitive
molecular manufacturing capability. We believe this is the responsible thing to
do. The machine we describe would make less powerful products, which we think
implies less disruption. What it would do is serve as a proof of principle and
stimulate discussion.
Chris has created a
Wise-Nano page containing his proposal. The page also contains another
X-prize proposal by Robert Freitas (author of Nanomedicine) that's intended to
jump-start diamondoid molecular manufacturing more directly. Although the
proposals have been submitted already, comments are welcomed at the Wise-Nano
"discussion" page.
CRN Blog Highlights
A few of the more interesting subject headings of the last month at our blog
site, which have inspired fascinating discussions, are:
