The document discusses the prevalence and types of sensors in various applications, including position, pressure, temperature, and force sensors, which enhance functionality in everyday life and industrial processes. It also covers the mechanisms and advantages of using sensors, particularly in sewing machines and wearables, while presenting comparisons between mechanical and computerized sewing machines. Furthermore, it addresses the design challenges in developing wearables with embedded sensors for monitoring health metrics.

2. SENSORS:
We live in a world of Sensors. You can find different types of Sensors in our
homes, offices, cars etc. working to make our lives easier by turning on the lights
by detecting our presence, adjusting the room temperature, detect smoke or fire,
make us delicious coffee, open garage doors as soon as our car is near the door and
many other tasks.
A sensor is a device that detects the change in the environment and responds to
some output on the other system. A sensor converts a physical phenomenon into a
measurable analog voltage (or sometimes a digital signal) converted into a human-
readable display or transmitted for reading or further processing.
The simplest example of a sensor is an LDR or a Light Dependent Resistor. It is a
device, whose resistance varies according to intensity of light it is subjected to.
When the light falling on an LDR is more, its resistance becomes very less and
when the light is less, well, the resistance of the LDR becomes very high.
APPLICATION OF SENSORS:
https://www.variohm.com/news-media/technical-blog-archive/applications-of-sensors-
Sensors are used for many different applications throughout different industries.
They are used in everyday applications as well as more industrial applications.
There is a multitude of different sensor types, the most popular categories we can
offer are; position sensors, pressure sensors, temperature sensors and load and
force sensors. Sensors are used in so many applications including motorsport,
agriculture, medicine, industrial, aerospace, agriculture and more.

3. POSITION SENSORS:
Fig1: Linear Position Sensors and Transducers
Position sensors are used to measure displacement and exact position whether this
is linear or rotary.
Application of position sensors:
 Medical application- Position sensors are used on oncology machines and
MRI machines to ensure the device is in the correct position for image
capture.
 Agriculture Applications – Steering systems in agricultural machinery use
both rotary and linear position sensors.
 Film Special Effects – Within special effect departments for films position
sensors are used. Various position sensors have been part of special effects
for some time now, featuring in some well-known, popular films.
PRESSURE SENSORS:

4. Fig2: Pressure transducers
The pressure sensor is a device for pressure measurement of gases or liquids.
Application of pressure sensors:
Pressure Transducers – Taking accurate measurements of real-time pressure. Our
range is constructed of stainless steel and come in different sizes to suit different
applications and environments. Measuring range to 5000bar.
Pressure Switches – To monitor pressure levels an alarm the user when a value is
reached. Often used in extractor fans, oxygen tanks and similar applications. We
carry our own range as well as a range from our trusted suppliers.
TEMPERATURE SENSORS:
Fig3: Temperature Transducers

5. A temperature sensor is a device used to measure temperature. This can be
air temperature, liquid temperature or the temperature of solid matter.
Applications of temperature sensors:
Thermistors – Discrete temperature sensors for use in different applications.
RTDs – Resistance temperature detectors often constructed of platinum or Nickle;
they can also be used as the sensing element within temperature probes.
Temperature Probes – A temperature sensing element within housing for use
within circuits. Differing housings make the probes versatile and easy to connect.
Our probes are manufactured onsite and can be custom built to suit customer
requirements.
Thermocouple – Very versatile and can measure temperature over a wide range.
Thermocouples are constructed of two differing metals. The combination of these
metals will determine their temperature measurement range.
LOAD AND FORCE SENSORS:
Load and force sensors, or load cells, are another of our product categories at
Various. They are used to measure weight and force, most load cells use internal
strain gauges, the deformation/ distortion of the strain gage is directly related to the
pressure the load cell is receiving. Load cells are available in various shapes, sizes
and capacities to suit different applications.

6. Application Of Load And Force Sensors
Weighing Scales – Weighing anything from sugar to dynamite and everything in
between. Weighing scales are the most common application for load cells and they
usually use a single point or shear beam load cells which are the most common
type of load cell. Weighing scales can include, kitchen scales, bathroom scales,
industrial scales and many more.
On-board Weighing – This process involves weighing the load of a heavy-duty
vehicle, such as a lorry, or an industrial tipper truck. The onboard load cell will
measure the load ensuring it does not exceed the maximum amount for the vehicle
which contributes to safety and efficiency.
Tracking Devices for Records – Within modern record players, load cells are
used to monitor the tracking force of the needle. This ensures the needle exerts just
the right amount of force to play the record with the clearest and most pleasant
sound.
ADVANTAGES AND DISADVANTAGES OF SENSORS
ADVANTAGES:
Deploying sensors and sensing technology has multiple benefits, including predictive and
preventive maintenance. They not only ensure that measurement data is transmitted
faster, but also increase accuracy, thereby improving process control, and enhancing asset
health.
The key advantages of sensors include improved sensitivity during data capture, almost
lossless transmission, and continuous, real-time analysis. Real-time feedback, and data
analytics services ensure that processes are active, and are executed optimally.
If we more precise it
 Accelerate processes and make them more accurate
 Collect process and asset data in real time

7.  Monitor processes and assets accurately, reliably, and continuously
 Increase productivity and reduce total cost of ownership
 Lower energy wastage
https://www.yokogawa.com/special/sensing-technology/usage/benefits-of-sensors/
DISADVANTAGES:
Narrow or limited temperature range. They are sensitive to temperature and,
therefore, the sensors typically are internally temperature compensated. It is better
to keep the sample temperature as stable as possible.
Short or limited shelf life. An electrochemical sensor usually has a shelf life of
six months to one year, depending on the gas to be detected and the environment in
which it is used.
Cross-sensitivity of other gases. While this is an advantage, it also can be a
disadvantage. Some sensors are subject to interference from other gases. It is
important to know what gases may cause interference with your sensor so you are
aware of potential false readings.
The greater the exposure to the target gas, the shorter the life span. Generally,
a one- to three-year life expectancy is specified. Low humidity and high
temperatures can cause the sensors’ electrolyte to dry out. Exposure to target gas or
cross-sensitivity gases also depletes the electrolyte.
USE OF SENSOR IN APPAREL INDUSTRY

8. SEWING MACHINE
A sewing machine is a machine used to stitch fabric and other materials together with
thread.
Sewing machines were invented during the first Industrial Revolution to decrease the
amount of manual sewing work performed in clothing companies.
The sewing machines have greatly improved the efficiency and productivity of the clothing
industry
UPPER PARTS OF SEWING MACHINE

9. 1. Spool pin 2. Thread guide
3. Tension disc 4. Take-up lever
5. Needle bar 6. Bobbin case
7. Presser foot 8. Presser foot lifter
9. Stitch regulator 10. Bobbin winder
11. Fly Wheel 12. Clutch or Thumb Screw
13. Slide Plate 14. Needle Plate or Throat Plate
15. Feed dog 16. Face plate
17. Spool pin for bobbin winding
FUNCTION
 Spool pin: It is fitted on top of the arm to hold the reel.
 Thread guide: It holds the thread in position from the spool to the needle.
 Tension disc: The two concave discs put together with the convex sides facing each
other. The thread passes between the two. The tension of the thread is adjusted by a
spring and nut which increases or decreases pressure
 Take up lever: It is a lever fitted to the body of the arm. It's up and down motion feeds
the thread to the needle and tightens the loop formed by the shuttle.
 Needle bar: This is a steel rod to hold the needle at one end with the help of a clamp. Its
main function is to give motion to the needle.

10.  Bobbin case: This moves into position to catch the top thread and form the stitch as the
needle is lowered into the bobbin chamber.
 Presser foot: It is fixed to the presser bar to hold the cloth firmly in position when
lowered.
 Presser foot lifter: A lever attached to the presser bar for raising and lowering the presser foot.
 Stitch regulator: This controls the length of the stitch.
 Bobbin winder: A simple mechanism used for winding thread on the bobbin.
 Fly Wheel: When this is made to revolve, it works the mechanism of the motion
 Clutch or Thumb Screw: This is in the center of the fly wheel and it engages and
disengages the stitching mechanism.
 Slide Plate: A rectangular plate, which facilitates the removal of the bobbin case without
lifting the machine.
 Needle Plate or Throat Plate: A semi-circular disc with a hole to allow the needle to pass
through it.
 Feed dog: This consists of a set of teeth fitted below the needle plate. It helps to move
the cloth forward while sewing.
 Face plate: A cover which on removal gives access to the oiling points on the needle bar,
presser bar and take-up lever.
 Spool pin for bobbin winding: Spool of thread is placed on this at the time of bobbin
winding.
LOWER PART OF SEWING MACHINE
1.Band Wheel leads the balance wheel through the belt connection.

11. 2.Band Wheel Crank- It moves the band wheel.
3.Belt
Guide- It holds the belt to its place.
4.Belt- It connects the balance wheel to the drive wheel.

12. MECHANISM OF SEWING MACHINE
1. Needle mechanism
This is the simplest mechanism of the three. The gray shaft drives a wheel (blue) and crankshaft
(green) that makes the needle (black) rise and fall. The crank converts the motor's rotary (round-
and-round) motion into the needle's reciprocal (up-and-down) motion.
2. Bobbin and shuttle mechanism

13. As we'll see in a moment, the shuttle and hook that make stitches from the needle thread have
to rotate somewhat faster than the needle. So the gray shaft has to turn the shuttle more
quickly, which it can do using gears (or pulleys wrapped round wheels of different sizes).
3. Feed-dog mechanism
The feed-dog moves the fabric through the machine at a steady speed, so ensuring stitches that
are of equal length. It works by moving upwards and forwards at the same time, which happens
through two interlinked mechanisms driven off the main shaft. I've drawn one of them (in the
center) as a cam (blue), an egg-shaped wheel that makes a lever (yellow) rock back and forth, so
pulling the feed dog from right to left and then back again. At the same time, a second crank
mechanism (green and red) moves the feed dog up and down. When these two movements are
synchronized, the feed dog works a bit like a shoe on the end of an upside-down leg. Normally, a
shoe on your leg moves down and backward, then lifts up and repeats the same movement,
pushing back against the ground so your body moves forward. But a feed dog (with the shoe in
effect pointing upward) moves upward and forward, "walking" the material through the machine
one step (one stitch!) at a time.
Stitch Forming Mechanisms:
Stitch formation is a basic and the most important task for sewing machine. The first step in
producing a stitch on a sewing machine is the formation of the needle thread loop. Proper
formation of this loop depends on the tendency of the thread to bulge away from the needle as it
is drawn upward after reaching the lowest point of its stroke – due to inertia and friction against
the material through which it passes. The stitch-forming mechanisms are the mechanical

14. components; with perfect synchronization between the parts, they form stitches. The stitch
forming mechanism includes a needle, a thread carrying looper and a retainer which enters the
looper thread loop and operates to retain and hold the same during the retracting movement of
the looper until the needle has entered the loo
SENSORS IN SEWING MACHINE
Sewing machines help stitch fabric, leather or other synthetic materials by using
a needle and two thread feeders. In the modern electric machines, the pedal uses
a Potentiometric controller similar to a ceiling fan. This consists of wound coil
with a moving carbon brush to control speed of the stitching motor. As the pedal
is pressed, variable current is fed to the motor.

15. The disadvantage of such a system is that the carbon brush wears out and the
stitching speed varies over time. A reed sensor array inside the pedal housing with
a magnet mounted under the pedal, actuates each of the the reed sensors one by
one as the pedal is depressed. The circuit that uses these multiple reed sensors is
based on the same principles as level sensors.
The output from the reed sensors is suitably decoded and is used to control the
motor speed. This way, the stitching speed remains constant with respect to the
depressed position of the foot pedal and there is no chance of dirt or oil affecting
the system. In more advanced sewing machine models, the number of mechanical
parts has been reduced and reed sensors are even used to change state of the
bottom bobbin thread feeders, whenever the shaft comes down and again when the
shaft starts moving up.
Application Classification
Applications are classified as Position Sensing, Pulse Counting, Electromagnetic or
Relay, Temperature Sensing or Magnet Biasing types. This application is classified
as follows and the link gives more information on best practices to help select the
most suitable AT band and matching magnet.
https://www.reed-sensor.com/applications/white-goods/sewing-machine-pedals/
https://www.freepatentsonline.com/y2020/0248348.html
The Pros of a Mechanical Sewing Machine
Some people use a mechanical sewing machine their entire life. They never feel need to upgrade
to a more complex machine. There are a number of reasons that they may prefer to sew on a
more basic sewing machine. Some of the pros include:
 Comfort – If you learned to sew on a mechanical machine or used one in a sewing class, it might
feel as familiar to you as eating with a fork! You know what to do to get the machine to sew the
way you want it and don’t have to take the time to figure out how to do something new. When
you are ready to start a project, you really are ready!
 Simplicity – Sewing is an ages old skill that has been passed down through the generations of
your family. You may have watched your grandmother sew on an old pedal-style machine. A
mechanical machine may be as modern as you want to get.
 You’re Allergic to Technology – Technology is great – when you know how to use it! There is a
learning curve involved when transitioning to a computerized machine. If you aren’t tech-savvy
and prefer to do things manually, then a mechanical machine will be the best choice for you.

16.  More Affordable – Mechanical machines cost significantly less than computerized ones. You can
purchase a top brand mechanical machine at a much lower cost of a top-end computerized one.
You shouldn’t pay for more sewing machine than you really need.
Pros To Purchasing a Computerized Machine
 Automated Features – Computerized machines include a number of features that save
time and make sewing easier. An automatic needle-threader is the biggest time-saver in
sewing! Other automatic features include tension adjustment, bobbin winder, thread
cutter, locking straight stitch function for reinforcing seams, and auto-tying to secure the
ends of the seam.
 More Precise Stitching – There’s no guesswork that goes into sewing with a
computerized machine. Many modern models can tell you the best stitch type and stitch
speed for the project and monitor the stitching for precise results.
 Versatility – If your sewing projects extend to quilting, embroidery, or heavy-duty
projects, a computerized machine has the versatility to handle them all. Thick or multi-
layer fabrics don’t present a problem like they will on mechanically machines.
 Machines for Specialized Sewing – There are machine models available that have a
larger throat for bulky projects or built-in embroidery designs for personalizing your
creations. Computerized machines offer on-screen tutorials that make it easier to choose
your designs and get the results you want effortlessly. You also have the option to
purchase embroidery designs online and transfer them from your computer to the sewing
machine. This means a virtually endless supply of new designs to try.
https://stitchers-source.com/mechanical-vs-computerized-sewing-machines-what-is-the-difference/
USE OF SENSORS IN WEARABLES
Why wearables?
As the internet of things continues to grow exponentially, wearables have
emerged as the latest frontier because of their enticing potential applications.
Wearables’ benefits include convenience, ease of use, and real-time service.
However, there are also daunting design and development challenges to
overcome if we are serious about expanding beyond the current applications.

17. The new wearables
 Built-in sensors in the fabrics
The least intrusive way of embedding sensors is building them into the fabric of
shirts, pants, socks, or shoes. Garments that fold and stretch to fit the body can
contain electronic components that collect data. Data generated from skin or
sweat in contact with the fabric could include the wearer’s heart rate, blood
pressure, blood glucose level, blood oxygen level, body temperature, and
activity.
For example
medical technology start-up Rhaeos has recently developed a wearable for non
-invasive monitoring of patients suffering from an accumulation of brain fluids.
Also, wearables can be used to monitor, track, and protect those dearest to a
consumer.
Rhaeos’ Flow Sense is a wireless, non-invasive
thermal flowsensor that can be mounted on a
patient’s neck overlying the shunt to detect the
presence and magnitude of cerebrospinal fluid.
LINK - https://www.eetimes.eu/iot-clothing-the-next-generation-of-wearables/
Design challenges
Being on the new frontier is undoubtedly exciting, but it is also challenging. In
addition to a flexible and easy-to-use human-machine interface, fabric needs
to be hardy, accurate, and self-sufficient.
Hardiness: Vibrations, collisions, everyday wear and tear; machine-washable

18. Once someone puts on, for example, a shirt made with IoT fabric, that shirt or
any other IoT apparel will experience the same vibrations, collisions, and
everyday wear and tear that the user experiences. Therefore, the fabric needs
to be toughened to stay intact and functional, more so if it is machine-washable.
As ruggedizing an IoT device typically involves adding protective material
around the device, it is unclear how this strategy can be applied to IoT fabric
without affecting its flexibility or wearability.
LINK - https://www.thehindu.com/sci-tech/technology/smart-clothes-
powered-with-sensors-can-help-monitor-health/article34899662.ece
The smart clothes contain miniaturized electronic circuits and sensors, which
will enable connection to smartphones, laptops, cars and other machines, and
will monitor the user’s health.
These ‘smart clothes’ are powered wirelessly through a flexible, silk-based coil
sewn on the textile and are laundry resistant, the team described in a STUDY
titled ‘Washable, breathable, and stretchable e-textiles wirelessly powered by
omni phobic silk-based coils.
The smart clothes contain miniaturized electronic circuits and sensors, which
will enable connection to smartphones, laptops, cars and other machines and
“will outperform conventional passive garments”, the team noted. It will also
assist in tracking health status and call for help if a user suffers an accident.
LINK- https://www.fierceelectronics.com/sensors/smart-textiles-provide-
better-way-to-connect-wearable-sensors
Smart' textiles provide better way to connect wearable sensors
wearable sensors and other smart devices have relied on Bluetooth or Wi-Fi
communications with the user’s smartphone to transmit and receive data. But as
wearable devices increase in number and complexity, researchers are looking
into other connection methods.
The National University of Singapore (NUS) have invented a new way for
wearable devices to interconnect. They incorporated conductive textiles into
clothing to dynamically connect several wearable devices at once. This 'wireless

19. body sensor network' allows devices to transmit data with 1,000 times stronger
signals than conventional technologies, thus improving device battery life.
Wireless networks of these wearable devices on a body have future applications
in health monitoring, medical interventions and human-machine interfaces.

20. Sewing machines help stitch fabric, leather or other synthetic materials by using a
needle and two thread feeders. In the modern electric machines, the pedal use a
Potentiometric controller similar to a ceiling fan. This consists of wound coil with
a moving carbon brush to control speed of the stitching motor. As the pedal is
pressed, variable current is fed to the motor.
The disadvantage of such a system is that the carbon brush wears out and the
stitching speed varies over time. A reed sensor array inside the pedal housing with
a magnet mounted under the pedal, actuates each of the reed sensors one by one as
the pedal is depressed. The circuit that uses these multiple reed sensors is based on
the same principles as level sensors.
The output from the reed sensors is suitably decoded and is used to control the
motor speed. This way, the stitching speed remains constant with respect to the
depressed position of the foot pedal and there is no chance of dirt or oil affecting
the system. In more advanced sewing machine models, the number of mechanical
parts has been reduced and reed sensors are even used to change state of the
bottom bobbin thread feeders, whenever the shaft comes down and again when the
shaft starts moving up.
Application Classification
Applications are classified as Position Sensing, Pulse Counting, Electromagnetic or
Relay, Temperature Sensing or Magnet Biasing types. This application is classified
as follows and the link gives more information on best practices to help select the
most suitable AT band and matching magnet.
https://www.reed-sensor.com/applications/white-goods/sewing-machine-pedals/