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smart dust also digital dust

noun [uncountable]

tiny electronic devices in the form of dust particles, which contain sensors and can be used for wireless communication

'The motes are so called because the scientists who made them intend them to be the grandfathers of a technology called smart dust: sensors the size of grains of sand which will be manufactured by the millions and scattered over the earth as required to help their owners – industrial, military, medical or snoopish – find out who's doing what, where, and when.'

The Guardian 14th September 2002

Smart dust is one of the latest additions to a proliferation in recent years of terms based on the adjective smart, to suggest the idea of specialist capability, often relating to computer-assisted technology. Smart weapon is a superordinate term for a wide range of hyponyms such as smart bomb, smart bullet, smart mine and smart missile. Smart material is a generic term for substances which exhibit special properties, such as smart metals or smart fluid (a fluid which can instantly turn solid without a change in temperature, when an electric current is passed through it). SmartStamp was the subject of an earlier BuzzWord article. The term smart dust, along with expressions such as smart sensor and smart marker, relates to the field of electronic, or smart, surveillance.

thousands of motes, collectively known as smart dust, can be spread throughout the atmosphere as a powerful means of collecting and monitoring data

Smart dust consists of a large amount of millimetre-scale electronic devices referred to individually as motes. Motes are as tiny as dust particles, and consist of a wireless transceiver (a device that can both transmit and receive communications) which has a remote sensor (mote is short for remote). Thousands of motes, collectively known as smart dust, can be spread throughout the atmosphere as a powerful means of collecting and monitoring data. The particularly interesting thing about smart dust motes is that they also have a networking capability: a single mote can only provide a very small piece of information, such as 'an object has moved', but hundreds of motes communicating with each other can provide a very detailed picture of what is happening somewhere. Smart dust therefore has an obvious application in military surveillance contexts, but there are other potential areas of use. For instance, hundreds or thousands of motes able to sense light and temperature could be placed in an office building and linked to computer systems regulating energy consumption. Smart dust could be used to monitor environments which might be hazardous to humans, such as outer space or chemical spillages, as well as hostile military zones. There are many other potential environmental and medical applications, such as monitoring traffic flow for the timing of traffic lights, or even monitoring the vital signs of the elderly or very sick.

Background – smart dust

Smart dust was originally the brainchild of a project at the University of California in Berkeley, USA. The US Defense Advanced Research Projects Agency began funding research into smart dust in 1998. The Berkeley project, entitled 'SMART DUST: Autonomous sensing and communication in a cubic millimeter' was led by Kristofer Pister, Professor of Electrical Engineering.

Pister estimates that though the current cost of motes is between $50 and $100, the price will fall to $1 within five years. If mass-produced, the potential benefits of smart dust in applications such as energy conservation could therefore significantly outweigh manufacturing costs.

by Kerry Maxwell, author of Brave New Words

This article was first published on 23rd July 2004.

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