"Smart dust" could soon be spying on you

By Duncan Graham-Rowe, New Scientist . 08.26.99

Cleanliness freaks have a new rationale for their pathological hatred of dust -- it could soon be spying on them.

Packed full of sensors, lasers and communications transceivers, particles of "smart dust" are being designed to communicate with one another. They could be used for a range of applications from weather monitoring to spying.

The tiny "motes" are being developed at the University of California, Berkeley, as part of a programme to produce the smallest possible devices that have a viable way of communicating with each other.

Each mote is made up of a number of microelectromechanical systems, or MEMS, wired up to form a very simple computer. At present each mote is 5 millimetres long, but Kris Pister, one of the developers, says that in future they could be small enough to remain suspended in air, buoyed by the currents, sensing and communicating for hours.

The latest version not only has a thick-film battery powering it but also a solar cell to recharge it. "This remarkable package has the ability to sense and communicate, and is self-powered," says Randy Katz, a communications engineer on the project. He presented the latest work at last week's Mobicom99 mobile computing meeting in Seattle.

MEMS are made using the same photolithographic techniques as integrated circuits, so once perfected they should be easy to mass-produce. Patterns are etched out of a silicon wafer to create structures such as optical mirrors or tiny engines.

Each mote in a smart-dust system will need to survive on extremely low power, while being able to communicate kilobits of data per second. To this end, says Katz, the team has designed motes that shut down parts of themselves when they are not being used.

The latest challenge has been to devise a system that enables the motes to communicate. Katz and his colleagues decided to use optical transceivers because of their low energy demand compared with radio communications. According to Pister they have already shown that they can monitor the dust 21 kilometres across San Francisco Bay. "There's no way you're going to get that kind of range except with optical devices," he says.

"The base station may actually reside in a hand-held unit, much like a pair of binoculars," says Katz. This would allow for simultaneous viewing of the scene from afar while superimposing any measured data on the image. He adds that this approach could be especially useful for hazardous applications such as detecting chemical weapons or sending the dust into space.

The next task is to build distributed intelligence into the dust to produce "swarm behaviour."

-- cin (cinlooo@aol.com), March 12, 2000

Answers

Gotta laugh! A scientist in a university, who is getting paid to work on this project, talks to a journalist and this is the kind of story we always seem to get.

It is in the interest of the scientist to make his work sound as viable as possible and to capture the public's iagination as a way of capturing the public's money. So a device that is currently 5mm (!) long gets touted as "soon" becoming the size of a dust mote.

How soon? Um, uh, it will be "in the future"!

And please note: neither the "soon" nor the "in the future" are contained in actual quotes from the scientist. That's probably because the scientist said something *much* more circumspect, in an attempt not to be thought insane by his colleagues. The journalist, however, didn't care if the scientist sounded insane, so long as the story was sensational enough to get printed instead of the picture of the adorable puppies dressed up in clown suits.

-- Brian McLaughlin (brianm@ims.com), March 12, 2000.

According to this article, they think they'll have them down to 1 millimeter by July of next year.

SMART DUST - Autonomous sensing and communication in a cubic millimeter

-- Hawk (flyin@high.again), March 12, 2000.

Hawk -- you seem like a nice guy, but you're just so damned gullible.

I believe that what the article says is that that's where "they'd like to be" by July 1. By July 1, I'd "like to be" living in my villa in France having won the lottery. Your guess, however, is as good as mine as to whether that will acutally happen.

-- E. H. Porter (E.H. Porter@just wondering.about it), March 12, 2000.

Scientists can now clone a human, and you doubt the credibility of spy-dust? Come on now. ;0)

-- cin (cinlooo@aol.com), March 12, 2000.

Your tax dollars at work. Another reason to become a non*tax*payer

http://www.ottoskinner.com
http://www.edrivera.com

-- A (A@AisA.com), March 13, 2000.

Pass the tin foil, please!

-- Somethings (JustAbitStrange@Here.com), March 13, 2000.

Brian:

5 mm, no problem. I have a dust ball in my office bigger than my G4.

Best wishes,,,,

Z

-- Z1X4Y7 (Z1X4Y7@aol.com), March 13, 2000.

Does anyone besides me remember the sci-fi gimmick of "slow glass"?

As you may or may not know, light travels modestly (several percent) slower in glass than in air (or in a vacuum) -- that's why glass lenses can bend or focus light beams and why a prism can spread out a spectrum. Different types of glass can slow light by different velocities because of the atomic properties of the elements in the glass.

Some sci-fi author, whose name escapes me right now, took that idea to an extreme and postulated an invention that could produce glass that slowed the velocity of light within it by factors of trillions or more rather than just by several percent, while retaining transparency. He termed this product "slow glass". Light that entered "slow glass" was slowed to such an extent that it took a significant amount of time to traverse the glass and emerge from the other side. This property led to many interesting uses.

For example, a vacation cabin could have a picture window made of six-month "slow glass". Whenever someone in the cabin (or outside it, for that matter) looked at the glass, the scene shown by the glass was whatever had been visible on the other side of the glass six months earlier. Summer vacationers could enjoy in August the authentic snowy winter scene that had been just outside the cabin the preceding February. In December they could be warmed by a sunny vista from the preceding June.

Back, sorta, to this thread ...

Another application of "slow glass" was spying. Slip into a meeting room, scatter some handfuls of tiny (small enough to stick to ceilings and walls upon contact) slow-glass beads with a wide range of time delays, then after the meeting go back in and vacuum some up. Back at the lab, scan though the retrieved beads until you found some whose time delays matched the interval since the meeting, then watch the meeting as the images emerged from those glass beads. And there were means of getting the slow glass to release its stored light faster than usual (but careful with that -- there's a lot of energy packed in there). Voila - a new spying technology.

Of course there were countermeasures. Folks about to have important meetings had their (windowless, of course) meeting rooms entirely spray-painted -- walls, floor, ceiling, tables, chairs, everything -- just long enough before the neeting for the paint to dry while the room was sealed against any access. The extrapolation of other measures is left as an exercise for the reader.

Now, "slow glass" is probably not going to be reality any time soon -- I don't know of any avenue of investigation that could possibly lead to material with such properties. But "smart dust" is based on reasonable extensions of existing technology.

-- No Spam Please (nos_pam_please@hotmail.com), March 13, 2000.

So this would explain the 6-month hangover after a night of drinking slow gin.

(I know i know sloe gin) ar ar ar =o)

-- cin (cinlooo@aol.com), March 13, 2000.

Oh heck, now I WILL have to chase them thare lil dust bunnies fer real!!!! =====gotta wonder, they do have eyes right? here bunny, here bunny..

-- consumer (shh@aol.com), March 13, 2000.

No Spam -

Wow, "slow glass". Hadn't come across a reference to that in ages. Lessee, Larry Niven, wasn't it? Hang about... *rummage, rummage, rummage*

No, it was Bob Shaw and "Light of Other Days" back in the early 70's. Wonderful story. Thanks for the reminder...

-- DeeEmBee (macbeth1@pacbell.net), March 13, 2000.