Seminar Report On Smart Dust.docx w4c70

SMART DUST Mohita Mudaliar Shri Dadaji Institute of Technology & Science Khandwa (M.P.) [email protected]

ABSTRACT The „Smart Dust‟ project is aiming to build an autonomous sensing, computing, and communication system packed into a cubicmillimeter mote, to form the basis of integrated, massively distributed sensor networks. So, this device will be around the size of a grain of sand and will contain sensors, computational ability, bidirectional wireless communications, and power supply, while being inexpensive enough to deploy by the hundreds. Smart Dust requires evolutionary and revolutionary advances in integration, miniaturization and energy management. If the project is successful, clouds of smart dust could one day be used in an astonishing array of application, from following enemy troop movements and hunting send missiles to detecting toxic chemicals in the environment and monitoring weather patters around the globe.

especially transistors have accelerated these strengths. The emergence of small computing elements, with sporadic connectivity and increased interaction with the environment, provides enriched opportunities to reshape interactions between people and computers and spur ubiquitous computing researches. Smart dust is tiny electronic devices designed to capture mountains of information about their surroundings while literally floating on air. Nowadays, sensors, computers and communicators are shrinking down to ridiculously small sizes. If all of these are packed into a single tiny device, it can open up new dimensions in the field of communications.

KEYWORD MEMS:- Micro electro mechanical sensors SRAM:- Static RAM(Random access memory) CCR:- Corner-cube rectorefflector HISTORY RF:- Radio frequency

INTRODUCTION The current ultramodern technologies are focusing on automationand miniaturization. The decreasing computing device size, increased connectivity and enhanced interaction with the physical world have characterized computing history. Recently, the popularity of small computing devices, such as hand held computers and cell phones; rapidly flourishing internet group and the diminishing size and cost of sensors and

The idea behind „smart dust‟ is to pack sophisticated sensors, tiny computers and wireless communicators in to a cubicmillimeter mote to form the basis of integrated, massively distributed sensor networks. They will be light enough to remain suspended in air for hours. As the motes drift on 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 the base station, miles away. Berkeley‟s Smart Dust project, led by Professors Pister and Kahn, explores the limits

on size and power consumption in autonomous sensor nodes. Size reduction is paramount, to make the nodes as inexpensive and easy-todeploy as possible. The research team is confident that they can incorporate the requisite sensing, communication, and computing hardware, along with a power supply, in a volume no more than a few cubic millimeters, while still achieving impressive performance in of sensor functionality and communications capability. These millimeterscale nodes are called “Smart Dust.” It is certainly within the realm of possibility that future prototypes of Smart Dust could be small enough to remain suspended in air, buoyed by air currents, sensing and communicating for hours or days on end.

mechanisms, in a single cubic millimetre. .Smart dust motes could run for years , given that a cubic millimetre battery can store 1J and could be backed up with a solar cell or vibrational energy source. The goal of the Smart Dust project is to build a millimeter-scale sensing and communication platform for a massively distributed sensor network. This device will be around the size of a grain of sand and will contain sensors, computational ability, bidirectional wireless communications, and a power supply. Smart dust consists of series of circuit and micro-electro-mechanical systems (MEMS) designs to cast those functions into custom silicon. Microelectromechanical systems (MEMS) consist of extremely tiny mechanical elements, often integrated together with electronic circuitry.

Smart dust sensor-laden networked computer nodes that are just cubic millimetres in volume. The smart dust project envisions a complete sensor network node, including power supply, processor, sensor and communications

Another timer controls the receiver. When that timer expires, the receiver powers up and look for an incoming packet. If it doesn‟t see one after a certain length of time, it is powered down again. The mote can receive several types of packets, including ones that are new program code that is stored in the program memory. This allows the to change the behavior of the mote remotely. Packets may also include messages from the base station or other motes. When one of these is received, the microcontroller is powered up and used to interpret the contents of the message. The message may tell the mote to do something in particular, or it may be a message that is just being ed from one mote to another on its

DISCRIPTION & WORKING OF SMART DUST way to a particular destination. In response to a message or to another timer expiring, the microcontroller will assemble a packet containing sensor data or a message and transmit it using either the corner cube retro reflector or the laser diode, depending on which it has. The corner cube retro reflector transmits information just by moving a mirror and thus changing the reflection of a laser beam from the base station. This technique is substantially more energy efficient than actually generating some radiation. With the laser diode and a set of beam scanning mirrors, we can transmit data in any direction desired, allowing the mote to communicate with other Smart Dust motes.

MODE OF COMMUNICATION 2.

Smart Dust‟s full potential can only be attained when the sensor nodes communicate with one another or with a central base station. Wireless communication facilitates simultaneous data collection from thousands of sensors. There are several options for communicating to and from a cubic-millimeter computer. Radio frequency and optical communications each have their strengths and weaknesses.

Radio Frequency:Radio-frequency communication is well understood, but currently requires minimum power levels in the multiple milliwatts range due to analog mixers, filters, and oscillators. If whisker-thin antennas of centimeter length can be accepted as a part of a dust mote, then reasonably efficient antennas can be made for radio-frequency communication. Semiconductor lasers and diode receivers are intrinsically small, and the corresponding transmission and detection circuitry for on/off keyed optical communication is more amenable to lowpower operation than most radio schema. Most important, optical power can be collimated in tight beams even from small apertures. Laser pointers are cheap examples of milliradian collimation from a millimeter aperture. To get similar collimation for a 1-GHz radiofrequency signal would require an antenna 100 meters across, due to the difference in wavelength of the two transmissions. As a result, optical transmitters of millimeter size can get antenna gains of one million or more, while similarly sized radio frequency antennas are doomed by physics to be mostly isotropic.

Moreover RF techniques cannot be used because of the following disadvantages :1. Dust motes offer very limited space for antennas, thereby demanding extremely short wavelength (high frequency transmission). Communication in this

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regime is not currently compatible with low power operation of the smart dust. Furthermore radio transceivers are relatively complex circuits making it difficult to reduce their power consumption to required microwatt levels. They require modulation, band filtering and demodulation circuitory.

There are several reasons for power advantage of optical links. 1. Optical transceivers require only simple baseband analog and digital circuitory . 2. No modulators,active band filters or demodulators are needed. 3. The short wavelength of visible or near infra red light (of the order of 1 micron) makes it possible for a millimeter scale device to emit a narrow beam (ie, high antenna gain can be achieved). OPTICAL COMMUNICATIONS Two approaches to optical communication are explored: ive reflective systems and active steered laser systems. In a ive communication system, the dust mote does not require an onboard light source. Instead, a special configuration of mirrors can either reflect or not reflect light to a remote source.

ive-reflective systems The ive reflective device consists of three mutually orthogonal mirrors. Light enters the CCR, bounces off each of the three mirrors and is reflected back parallel to the direction it entered. In MEMS version, the device has one mirror mounted on a spring at an angle slightly askew from perpendicularity to the other mirrors. The mirror‟s low mass allows the CCR to switch between 0 and 1 states up to a thousand times per seconds, using less than a nanojoule per 0-1 transition. A 1-0 transition on the other hand is practically free because damping the charge stored in the electrode to the ground requires almost no energy.

ive communication system suffers several limitations. Unable to communicate with each other, motes rely on a central station equipped with a light source to send and receive data from other motes. Also, because CCR reflects only a small fraction of the light emitted from a base station, the systems range cannot easily extend beyond 1 km. Active- steered laser systems For mote- to – mote communication, an active steered laser communication system uses an onboard light source to send a tightly collimated light beam towards an intended receiver. Steered laser communication has the advantage of high power density. This system allows communication over enormous distances using millwatts of power.

Here, a laser emits an infrared beam that is collimated with a lens. This lens directs the narrow laser beam into a beam steering mirror, aiming the beam towards the intended receiver.

CURRENT ADVANCEMENT Micro robotics: Add legs or wings to smart dust and we get micro robots. Like smart dust, these synthetic insects will sense, think, and communicate. In addition they will have the ability to move about and interact physically with their environment. Micro machining can be used to build micro actuators and micro mechanisms, forming legs and wings, which are integrated with other smart dust components.

The crawling microbot consume only tens of micro watts of power; the motors can lift more than 130 times the robot‟s own weight. The flying microbot have a wing span of 10-25 mm and will sustain autonomous flight. Developers folded 50 micron thick stainless steel into desired shape to create the wings and exoskeleton. Piezoelectric motors attached to the exoskeleton actuate the wings. These legged and winged microbots will consume a total power of less than 10 milliwatts, provided by onboard solar cells.

environmental comfort sensors sewn into our clothes, continuously talking to our workspaces which will deliver conditions tailored to our needs.

APPLICATIONS

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Weapons Land or networks.

stockpile monitoring. space communication

Chemical or biological sensors.

Monitoring environmental conditions that affect crops and livestock.

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Building virtual keyboards.

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Providing interfaces for the disabled.

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Product quality monitoring.

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Internal space craft monitoring.

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Individual dust motes can be attached to the objects one wishes to monitor or a large no: of dust motes may be dispersed in the environment randomly.

Dust motes may be used in places where wired sensors are unusable or may lead to errors. Eg:Instrumentation of semiconductor processing chambers,wind tennels, rotating machinery etc. May be used in biological research eg:- to monitor movements & internal processes of insects.

SOME MORE APPLICATONS ARE :Defense related sensor networks.Civil and military applications where chemical & biological agents in a battle field are detected. Virtual keyboard Glue a dust mote on each of your fingernails. Accelerometers will sense the orientation and motion of each of your fingertips, and talk to the computer in your watch. Combined with a MEMS augmented-reality heads-up display, your entire computer I/O would be invisible to the people around you.

Inventory Control Smart office spaces The Center for the Built Environment has fabulous plans for the office of the future in which environmental conditions are tailored to the desires of every individual. Maybe soon we'll all be wearing temperature, humidity, and

Environmental protection: Identification and monitoring pollution. Habitat Monitoring: - 0bserving behavior of animals in their natural habitat.

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In Hospitals: - Nurses can keep track of patient movements.

Health and Wellness Monitoring : - Enter human bodies and check for physiological problems.

In military: - These sensors can detect enemy movement and also chemical substances.

In Spying: - Monitoring activities in inaccessible areas, accompany soldiers and alert them to any poisons or dangerous biological substances in the air.

In Factories or Farm: - The sensors can adjust the temperature and humidity to the needs.

For Security: - Smart Dust detects any movement, noise or smoke and alert people about danger.

ADVANTAGES

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Miniaturization effort could help solve one of the most pressing economic problems of the day: run away energy costs. Once attached to building‟s walls, the sensors would form a network relaying data about each room‟s temperature, light and humidity to central computer that would regulate energy usage for a fraction of the cost of current climate control systems. The emerging smart energy technologies potentially could save nations on electricity costs, as buildings drain away more than a third of the total energy supply.

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Small in size and light in weight.

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Solves most pressing economic problem of the day: run away energy cost.

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As the batteries are used as a power sources, it saves electricity cost.

DISADVANTAGES

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The main concern is privacy. Because it is so tiny, this device can be used to spy on people without their approval.

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Another concern is the security of the information transmitted through this sensors. Like in any other computer, hackers can brake into the system and steal or modify important data.

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A major challenge is to incorporate all functions while maintaining very low power consumption, thereby maximizing operating life; given the limited volume available for energy storage. The functionality envisioned for smart dust can be achieved only if total power consumption of a dust mote is limited to microwatt levels, and if careful power management strategies are utilized.

CONCLUSION

Smart dust is made up of thousands of sandgrain-sized sensors that can measure ambient light and temperature. The sensors -- each one is called a "mote" -- have wireless communications devices attached to them, and if you put a bunch of them near each other, they'll network themselves automatically. These sensors, which would cost pennies each if mass-produced, could be plastered all over office buildings and homes. Each room in an office building might have a hundred or even a thousand light- and temperature-sensing motes, all of which would tie into a central computer that regulates energy usage in the building. Taken together, the motes would constitute a huge sensor network of smart dust, a network that would give engineers insight into how energy is used and how it can be conserved. In a dust-enabled building, computers would turn off lights and climate control in empty rooms. During peak energy usage times, air conditioners that cool servers - which drain a lot of the tech world's power -would be automatically shut off, and then turned on again if the servers get too hot. Thus it can very lead to world‟s energy conservation solutions.

REFRENCE

 www.google.com

 www.bing.com

 www.latestscience.org

 www.scienceworld.com