08-16-2017, 10:19 PM
Smart dust devices are tiny wireless micro electro mechanical sensors (MEMS) that can detect anything ranging from light to vibrations.they are referred to as motes. Modern technology has led to its miniaturisation and these cen contain sensors, computing circuits, bi-directional wireless communications technology and a power supply. They gather data, do computations communicate with other motes .
They have wide appications: engineers can mix them into concrete to monitor the health of the concrete, military use them to gather data about battlefields.
Introduction
Motes is also called smart dust and wireless sensing networks. Originally developed by Defense Advanced Research Projects Agency (DARPA), U.S. Department of Defense central research and development group and Santa Clara the California-based chip making giant. The main objective of MOTES is to integrate the sensor, power-supply, computing, and communications functions into a single silicon platform that can collect, analyze, and store data and then create an intelligent response.
THE BASIC IDEA
-The core of a mote is a small, low-power, low-cost, computer.
-The computer tracks one or more sensors.sensors for temperature, light, sound, position, acceleration, vibration are all included.
-This computer connects to the world outside and with other motes with a radio link
Power sources can be mainly batteries, or solar power or even something exotic like vibration power.
TECHNOLOGIES USED
The main technologies involved are:
# MEMS (Micro-Electro-Mechanical Systems)
# Digital Circuitry
# RF (Radio Frequency) Wireless Communication Technology
MEMS SENSORS
They are the integration of mechanical elements, sensors, actuators, and electronics on a common silicon substrate through micro fabrication technology. Sensors collect information from the environment by measuring mechanical, thermal, biological, chemical, optical or magnetic phenomena. The electronics part then processes the information from the sensors and through its decision making capability , direct the actuator to respond by moving, positioning, regulating, pumping and filtering, thereby producing an outcome .
DIGITAL CIRCUITRY
electronic integrated circuits form the brains of the system MEMS augments this by providing input to it. sophistication circuits can be placed on a single silicon chip at a low cost.
WIRELESS COMMUNICATION
This is used for sending and receiving data from distributed sensor network or smart dust systems.power constraints are there and they must communicate over several hundred meters and the data transfer rate must be minimum of 1 kbps. It must support bi-directional communication between a central transceiver and up to 1000 dust motes. The central transceiver must be able to resolve the position of each dust mote and range must be several 100 meters. average power must not exceed one microwatt.
OPERATION OF MOTES
There are different timers running on the motes. When a timer expires, it powers up a part of the mote to carry out a job, then powers off. Some timers control the sensors, which takes a sample, and converts it to a digital word,then stored in the SRAM , or the micro controller performs more complex operations.
Another timer controls the receiver which looks for an incoming packet. If this packet i s not recieved, it is powered off. The mote can receive data packets that are even new program code that is stored in the program memory. Thus user can change the behavior of the mote remotely.
For full seminar report:
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The following page link has some more details:
http://careers-india2009/09/22/smart-dust-devices/