Kamlesh Kumar 100103151 Page 1
Sensors in Everyday Life
Mr. Pramod Kumar Singh
Roll No. 100103151
Class Roll No. 23
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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.
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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
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 _
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
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 2Na + 3N2
10Na + 2KNO3 K2O + 5Na2O+ N2
K2O + Na2O SiO2 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
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An anemometer is a device for measuring wind speed, and is a common weather
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
A short cuff requires special attention in
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.
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
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.
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
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
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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.
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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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
A microphone (colloquially called a mic or mike; both pronounced /ˈmaɪk/) 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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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.
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_
Wireless Dynamics Sensor System
Relative Humidity Sensor
Respiration Monitor Belt