Project Reporton

Sensors in Everyday Life

Submitted To:Mr. Pramod Kumar Singh

Submitted By: Kamlesh Kumar Roll No. 100103151 Class Roll No. 23 EC’C’

Kamlesh Kumar 100103151 Page 1

Acknowledgement

This is a great opportunity to acknowledge and to thanks all those persons without whose

support and help this project would have been impossible. We would like to add a few

heartfelt words for the people who were part of this project in numerous ways.

I would like to thanks to our project guide “Mr. Pramod Kumar Singh”, for his

indefatigable guidance, valuable suggestion, moral support, constant encouragement and

contribution of time for the successful completion of project work.

Kamlesh Kumar

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TABLE OF CONTENT

S.NO TOPIC PAGE NO.

1. Introduction to Sensors 4-4

2. Sensors in Everyday Life 4-4

3. Sensors In Industry 5-5

4. Sensors For Safety and Security 5-5

5. Sensors In the Classroom 6-6

6. Sensors in Education 6-6

7. Some most common Sensors 6-6

8. Accelerometers 6-7

9. Anemometer 7-8

10. Blood Pressure Sensor 8-8

11. CO2 Gas Sensor 8-9

12. Current Sensors 9-10

13. ECG Sensor (Heart Rate Monitor) 10-10

14. Ethanol Sensor 10-11

15. Flow Rate Sensor 11-11

16. Force Sensors 11-11

17. Light Sensor 12-12

18. Microphone 12-12

19. Touch Sensor 13-13

20. Ohaus Balances 15-15

21. several other sensors 14-14

22. References 15-15

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Introduction to Sensors

A sensor (also called detector) is a converter that measures a physical quantity and converts it into a signal which can be read by an observer or by an (today mostly electronic) instrument. For example, a mercury-in-glass thermometer converts the measured temperature into expansion and contraction of a liquid which can be read on a calibrated glass tube. A thermocouple converts temperature to an output voltage which can be read by a voltmeter. For accuracy, most sensors are calibrated against known standards.

Sensors in Everyday Life

Seismic monitors provide an early warning system for earthquakes.

The latest sensor equipment includes heart rate, electrical voltage, gas, light, sound,

temperature, and distance sensors. Data is collected via the sensors and then transmitted to

the computer. Up to date software is used to collect, display and store the experimental data.

The computer software can then display this data in different formats - such as graphs, tables

or meter readings, which make it easy for students to understand the process and bring

science to life.

The significance of sensor technology is constantly growing. Sensors allow us to monitor our

surroundings in ways we could barely imagine a few years ago. New sensor applications are

being identified everyday which broadens the scope of the technology and expands its impact

on everyday life.

Here are just a few examples of how sensors are being used:

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Sensors In Industry

On the factory floor, networked vibration sensors warn that a bearing is beginning to fail.

Mechanics schedule overnight maintenance, preventing an expensive unplanned shutdown.

Inside a refrigerated grocery truck, temperature and humidity sensors monitor individual

containers, reducing spoilage in fragile fish or produce.

In the Environment

Networks of wireless humidity sensors monitor fire danger in remote forests. Nitrate sensors

detect industrial and agricultural runoff in rivers, streams and wells, while distributed seismic

monitors provide an early warning system for earthquakes. Meanwhile built-in stress sensors

report on the structural integrity of bridges, buildings and roadways, and other man-made

structures.

Sensors For Safety and Security

Firefighters scatter wireless sensors throughout a burning building to map hot spots and flare-

ups. Simultaneously, the sensors provide an emergency communications network. Miniature

chemical and biological sensors in hospitals, post offices, and transportation centres raise an

alarm at the first sign of anthrax, smallpox or other terror agents

.

 

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Sensors In the Classroom

Sensor technology provides teachers with an exciting alternative to the time consuming task

of manually logging and observing science experiments. Instead of using stopwatches,

thermometers and barometers, students are using sensors and powerful software to collect

and analyze data as they are carrying out their experiments. This provides more accurate

readings than the old manual methods and data is collected in a more exciting way.

Sensors in Education

Sensor technology can have a huge impact on the way science is thought in the classroom.

This technology can bring valuable improvements in the teaching and learning of science and

mathematics. As the sensors are easy to use and understand, they can be used across a wide

range of ages and abilities. Sensor technology provides students with a means of seeing,

interpreting, exploring and communicating relationships graphically.

The investigative approach to collecting and analyzing data is particularly useful for students

who find science difficult. Students can repeat experiments several times due to the speed at

which data is collected. This approach encourages higher order thinking while allowing

students to engage in authentic investigation rather than prescriptive experiments that have

pre-determined outcomes. As science syllabuses move away from content towards process,

the use of modern measuring tools should be evident in every classroom.

Some most common Sensors by Type Alphabetically are _

Accelerometers

Accelerometer sensors measure the acceleration experienced by the sensor and anything to

which the sensor is directly attached. Accelerometer sensors have many applications. The

most common commercial application is impact sensors for triggering airbag deployment in

automobiles: when the acceleration exceeds 30 to 50 g’s,† an accident is assumed and the

airbags

deploy.

Frontal crash scenario: Car crashes into an obstacle (wall) at 20+ mph Sensors detect the

deceleration and inflator unit activated

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Deployment sensitivity: To guard against accidental inflation on hard braking, sensors

detect collisions into a solid barrier at speeds greater than 8-14 mph only as impacts. An

electric current is used to heat a filament wire that ignites the NaN3 capsules, producing N2:

2NaN3 à 2Na + 3N2

10Na + 2KNO3 àK2O + 5Na2O+ N2

K2O + Na2O SiO2à alkaline glass (safe, unignitable)

130 g of NaN3 produces 67 ltrs of Na

The airbag then inflates fully at speeds > 320mph within 0.05s of crash. For maximum

safety, occupant must have seat belt on and sit with chest 10” from steering wheel

Immediately after full inflation, the airbag deflates through tiny pores on the surface within

0.3s

Anemometer

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An anemometer is a device for measuring wind speed, and is a common weather

station instrument.

An anemometer is a weather instrument used to measure wind speed and direction. There are

three main types of anemometers ranging from basic to complex.

The spinning cup anemometer only measures wind speed. This is the most common and basic

of the anemometer models. It includes 3 to 4 cups mounted on a vertical pole. The cups catch

the blowing wind and turn the pole. Each time the anemometer makes a full rotation, the

wind speed is measured by the number of revolutions per minute (RPM). The number of

revolutions is recorded over time and an average is determined.

Blood Pressure Sensor

An occlusive cuff is placed on arm and

inflated to P > SP. Then the cuff is

deflated gradually and the measurement of

blood flow is done

The occlusive cuff should be of a correct

size in order to transmit the pressure to the

artery evenly and thus to obtain accurate

results

A short cuff requires special attention in

placement. Longer

cuff reduces this problem.

The cuff should be placed at the heart level in order to minimize the hydrostatic effects

CO2 Gas Sensor

A carbon dioxide sensor or CO2 sensor is an instrument for the measurement of carbon

dioxide gas. The most common principles for CO2 sensors are infrared gas sensors (NDIR)

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and chemical gas sensors. Measuring carbon dioxide is important in monitoring indoor air

quality and many industrial processes.

NDIR sensors are spectroscopic sensors to detect CO2 in a gaseous environment by its

characteristic absorption. The key components are an infrared source, a light tube, an

interference (wavelength) filter, and an infrared detector. The gas is pumped or diffuses into

the light tube, and the electronics measures the absorption of the characteristic wavelength of

light. NDIR sensors are most often used for measuring carbon dioxide. The best of these have

sensitivities of 20–50 PPM.

Current Sensors

For a given current flow, a proportional magnetic field is produced around the current

carrying conductor. NK Technologies current sensors measure this field using one of two

technologies. For DC currents, we use "Hall Effect" while for AC currents, we use

"Inductive" technology.

Hall effect and induction are noncontact technologies based on the principle that for a given

current flow, a proportional magnetic field is produced around the current-carrying

conductor. Both technologies measure this magnetic field, but with different sensing methods

The inductive sensor consists of a wire-wound core and a signal conditioner. The current

conductor passes through a magnetically permeable core that magnifies the conductor's

magnetic field. AC current constantly changes potential from positive to negative and back

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again, generally at the rate of 50 Hz or 60 Hz. The expanding and collapsing magnetic field

induces current in the windings. This is the principle that governs all transformers.

ECG Sensor (Heart Rate Monitor)

A heart rate monitor is a personal monitoring device which allows a subject to measure his or

her heart rate in real time or record his or her heart rate for later study. It is largely used by

performers of various types of physical exercise.

Ethanol Sensor

A fuel cell sensor is an electrochemical device in which the substance of interest, in this case

alcohol (ethanol), undergoes a chemical oxidation reaction at a catalytic electrode surface

(platinum) to generate a quantitative electrical response. The position on the catalyst where

this occurs is known as an “active site” and is on an intermolecular scale, measured in

nanometers.

Pt + H2SO4

C2H5OH --------------------------------CH3CHO + 2 H+ + 2 E

(ethanol) Sensor action Acetic Acid (Ethanoic Acid)

In summary, as this oxidation of the ethanol molecule takes place a new molecule acetic acid

(ethanoic acid) is produced altering the electrical properties of the electrode. This alternation

creates the peak output from the fuel cell. This process is referred to as Heterogeneous

Catalysis.

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Flow Rate Sensor

A flow sensor is a device for sensing the rate of fluid flow. Typically a flow sensor is the

sensing element used in a flow meter, or flow logger, to record the flow of fluids. As is true

for all sensors, absolute accuracy of a measurement requires a functionality for calibration.

There are various kinds of flow sensors and flow meters, including some that have a vane that

is pushed by the fluid, and can drive a rotary potentiometer, or similar devices.

Force Sensors

In a typical quartz-based force sensor, a charge-collection electrode is sandwiched between

two quartz-crystal elements. The quartz elements are oriented to supply the same polarity

voltage to the electrode when compressed, while the opposite polarity is applied to the sensor

housing. This assembly resides between two mounting disks held together by an elastic,

beryllium-copper stud and then weld-sealed within the enclosure to prevent contamination.

The stud preloads the quartz elements to assure all parts are in intimate contact and to provide

good linearity and tensile-force measurements.

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Light Sensor

A light sensor, as its name suggests, is a device that is used to detect light. There are many

different types of light sensors, each of which works in a slightly different way.

A photocell orphotoresistor, for example, is a small sensor that changes its resistance when

light shines on it; they are used in many consumer products to determine the intensity of

light. A charged coupled device (CCD) transports electrically charged signals, and is used as

a light sensor in digital cameras and night-vision devices. Photomultipliers detect light and

multiply it.

Microphone

A microphone (colloquially called a mic or mike; both pronounced / ̍ m aɪ k / )[1] is an acoustic-

to-electric transducer or sensor that converts sound into anelectrical signal. Microphones are

used in many applications such as telephones, tape recorders, karaoke systems, hearing

aids, motion picture production, live and recorded audio engineering, FRS

radios, megaphones, in radio and television broadcasting and in computers for recording

voice, speech recognition, VoIP, and for non-acoustic purposes such as ultrasonic checking

or knock sensors.

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Touch Sensor

A touch switch is a type of switch that only has to be touched by an object to operate. It is

used in many lamps and wall switches that have a metal exterior as well as on public

computer terminals. A touchscreen includes an array of touch switches on a display. A touch

switch is the simplest kind of tactile sensor.

Ohaus Balances

Sound Level Meter

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A sound level meter or sound meter is an instrument which measures sound pressure level,

commonly used in noise pollution studies for the quantification of different kinds of noise,

especially for industrial, environmental and aircraft noise. However, the reading from a sound

level meter does not correlate well to human-perceived loudness, which is better measured by

a loudness meter. The current international standard that specifies sound level meter

functionality and performance is the IEC 61672:2003.

There are several other sensors like_

Spectrometers

Spirometer

Temperature Sensors

Turbidity Sensor

UV Sensors

Wireless Dynamics Sensor System

pH Sensors

Polarimeter (Chemical)

Power Amplifier

Pyranometer

Relative Humidity Sensor

Respiration Monitor Belt

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References

http://en.wikipedia.org/wiki/

http://www.pasintl.com/electrochemical-fuel-cell-sensors/fuel-cell-sensor-technologies.html

http://www.vernier.com/products/sensors/

https://www.google.co.in/imghp?hl=en&tab=wi

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