From: "DS" <email@example.com>
To: "InTheShadows" <firstname.lastname@example.org>,
Subject: [isml] Floating 'Smart Dust' May Be New Spy in the Sky
Date: Tue, 21 Nov 2000 19:25:48 -0500
>From National Geographic,
Floating 'Smart Dust' May Be New Spy in the Sky
By The San Francisco Chronicle
November 21, 2000
If Kristofer Pister has his way, we will never think about dust in
quite the same way again.
Pister is leading a team of researchers at the University of
California at Berkeley that is developing tiny, electronic devices
called "smart dust," designed to capture mountains of information
about their surroundings while literally floating on air.
If the project is successful, clouds of smart dust could one day be
used in an astonishing array of applications, from following enemy
troop movements and hunting Scud missiles to detecting toxic chemicals
in the environment and monitoring weather patterns around the globe.
The idea behind smart dust is to pack sophisticated sensors, tiny
computers and wireless communicators onto minuscule "motes" of silicon
light enough to remain suspended in air for hours at a time. As the
motes drift on the wind, they can monitor the environment for light,
sound, temperature, chemical composition and a wide range of other
information, and beam that data back to a base station miles away.
Pister, an associate professor of electrical engineering and computer
science at UC Berkeley, said he came up with the idea for smart dust
eight years ago at a conference on future technology. "I realized that
sensors, computers and communications were going to shrink down to
ridiculously small sizes," he said. "So why not package them into a
single, tiny device?"
Pister submitted a proposal to the federal Defense Advanced Research
Projects Agency, a branch of the Defense Department, which agreed to
provide about $1.2 million over three years to fund the project.
Each mote of smart dust is composed of a number of
microelectromechanical systems, or MEMS, wired together to form a
MEMS are made using the same photolithographic techniques used to make
computer chips. Once perfected, they are relatively easy and
inexpensive to mass-produce. But unlike computer chips, which are
solid, MEMS contain moving parts.
Patterns are etched with light into a silicon wafer to create
structures such as optical mirrors or tiny engines. Each mote contains
a solar cell to generate power, sensors that can be programmed to look
for specific information, a tiny computer that can store the
information and sort out which data is worth reporting, and a
communicator that enables the mote to be "interrogated" by the base
Later versions may also contain a lilliputian lithium battery so the
motes can operate at night.
While much of the technology used to develop smart dust already
exists, the UC researchers are breaking new ground by integrating
these systems into remarkably small, self-powered packages.
"We are pushing the limits of miniaturization, integration and power
management," said Brett Warneke, a graduate student in electrical
engineering working on the project.
In one experiment to demonstrate the viability of the concept,
researchers deployed a golf ball-sized device on Twin Peaks in San
Francisco that measured weather conditions in the area - temperature,
light, barometric pressure and humidity - and beamed that information
back to a base station in Berkeley, more than 13 miles away.
So far, the smallest device the UC researchers have developed is 62
cubic millimeters - about the size of a pea - but Pister expects to
shrink the devices to a nearly microscopic cubic millimeter by next
summer. At that scale, they would be truly like dust: small enough to
remain suspended in air, buoyed by the currents, sensing and
communicating for hours.
One of the biggest hurdles the UC researchers face is building a
mechanism that can survive on extremely low power but is still capable
of sensing, sorting and sending vast amounts of information. For that
reason, they have designed a computer operating system called Tiny OS
that can function on a mere 512 bytes of RAM - about the amount of
processing power found in a toaster.
The UC researchers are also experimenting with an ingenious optical
communicator called a corner-cube reflector, which enables the motes
to communicate while expending virtually no energy.
Pioneered at the University of California at Los Angeles, the
reflector is essentially a tiny, hinged mirror that can flash millions
of Morse code-like signals per second. When a smart mote is
illuminated by a laser fired from the base station, the station can
"read" the code reflected in the twitching mirror. The mirror itself
is powered by electrostatic energy, the force that makes your socks
cling together when they come out of the dryer.
Smart dust devices are now capable of communicating only with a single
base station, but will eventually be able to share information with
each other. Such a system of "massively distributed intelligence"
will vastly increase their ability to organize and communicate
"They will be able to do things collectively that they can't do
individually, just like an ant colony," Warneke said. "An individual
ant isn't very smart, but collectively, they are very smart."
Researchers are exploring a number of methods for deploying smart
dust. One involves the use of tiny, unmanned aircraft that would spray
motes over an area like a miniature crop duster and relay the
resulting information back to a base station. MLB Co., a Palo Alto
firm that develops experimental aircraft, has already built such a
plane - an 8-inch radio-controlled aircraft equipped with a video
camera that can stay aloft for 18 minutes at a speed of 60 mph.
MLB's "micro air vehicle" could be useful in a battlefield situation
where low clouds impeded satellite surveillance. The tiny, unmanned
plane could soar undetected above the battlefield, disperse a swarm of
smart dust and begin relaying a stream of data about the movement of
enemy troops and equipment.
The UC researchers are also exploring ways to prolong the time smart
dust remains airborne by adding "wings" like those on maple seeds. A
cubic-millimeter-sized mote dropped at 30,000 feet would normally take
five hours to reach the ground. By attaching wings, the researchers
hope to extend that period two- or three-fold.
Other researchers are attaching tiny legs to the motes to create
so-called microbots or smart insects. Instead of wafting aimlessly
through the air like dust, microbots could be programmed to perform
specific tasks, such as crawling through a collapsed building to
search for warm bodies.
"Smart dust is like the brain, and we're building the body," said
Richard Yeh, a graduate student researcher specializing in
microrobotics who is working on the smart dust project.
Yeh and his colleagues have already developed the basic components of
a smart insect - tiny, jointed members, which function as legs, and
minuscule motors, the equivalent of muscles. All that remains is to
connect the components to a mote of smart dust, a step Yeh expects to
accomplish within weeks.
Although the smart dust research is supported by the Defense
Department, its proponents see many nonmilitary applications for it,
many for motes that would stay in one place.
CRUNCHLESS CAP'N CRUNCH
They could be used to detect fires and earthquakes, tailor the climate
in office buildings to suit the preferences of individual workers, and
monitor product quality from factory to consumer (a mote of smart dust
could tell, for example, if a box of Cap'n Crunch had been exposed to
high humidity, and lost its crunch, or if a crate filled with delicate
electronic components had been dropped).
Like many other new technologies, smart dust clearly has the potential
to be used for nefarious purposes. Foreign governments (or our own),
terrorist organizations, criminals and industrial spies could use
high-tech motes to spy.
"This is a technology of total surveillance," said Richard Sclove,
founder of the Loka Institute, a nonprofit organization in Amherst,
Mass., that studies the social implications of technology.
"I have no doubt that there will be plenty of benign and wonderful
applications of this technology, but it's easier to imagine the lousy
ones. The CIA and the National Security Administration would love to
get their hands on this, and there's no way to control what they do
While Pister acknowledges the possibility that smart dust could be
misused, he says the potential benefits of the technology "far, far
outweigh" any risks.
"You can find harmful effects in everything," added Yeh. "But the
threat is small. If a rogue state wanted to use them to spy on us,
they could do it, but not much more. They probably couldn't carry
enough poison or gas to do much damage."
The specter of millions, or even billions, of electronic motes
drifting around the globe has also raised concerns about the potential
ill effects on the environment and health.
But Pister dismissed such concerns. "Even in my wildest imagination, I
don't think we'll ever produce enough smart dust to bother anyone," he
said. "Most of these materials are not environmentally
harmful. Essentially they are made out of sand, and that's not toxic."
Potentially, the most dangerous element of a smart dust mote would be
the lithium battery, Pister says, but its minuscule size would pose
"A small town throws away more batteries per year than we can
distribute across the entire universe," he said. "It's really a
question of trade-offs. If you can sprinkle a few ounces of battery
over a rain forest and thereby get a better understanding of the
ecology, that's a trade-off worth making."
And what if someone accidentally inhaled a mote of smart dust? "If by
ill chance you did inhale one, it would be like inhaling a gnat. You'd
cough it up post-haste. Unpleasant, but not very likely."
(c) 2000 The San Francisco Chronicle
-- Dan S
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