Maruti Suzuki India Limited, formerly known as Maruti Udyog Limited, is an automobile manufacturer in India. It is a subsidiary of Japanese automobile and motorcycle manufacturer Suzuki Motor Corporation. At MSIL I worked at Quality Control Department and the project I had worked upon was AOI - Automated Optical Inspection AOI, automated optical inspection is an automated vision inspection of PCB during the manufacturing process. It is used to scan the inner layers and outer layers of PCB after the processes of etching and stripping. After scanning by AOI machine, the defects which do not meet the manufacturer’s requirement will be identified by the machine. In this way, AOI can detect problems early in the production process, so faults would not be passed to next production process and production cost could be saved. AOI uses visual methods to monitor printed circuit boards for defects. They are able to detect a variety of surface feature defects such as nodules, scratches and stains as well as the more familiar dimensional defects such as open circuits, shorts and thinning of the solder. They can also detect incorrect components, missing components and incorrectly placed components. As such they are able to perform all the visual checks performed previously by manual operators, and far more swiftly and accurately.

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A REPORT OF 12 WEEKS INDUSTRIAL TRAINING
AT
GURGAON PLANT
SUBMITTED IN PARTIAL FULFILLMENT OF THE
REQUIREMENT FOR THE
AWARD OF THE DEGREE OF
BACHELOR OF TECHNOLOGY
(Mechatronics Engineering)
MAY-AUGUST, 2018
SUBMITTED BY:
ABHISHEK MITTAL
DEPARTMENT OF MECHANICAL ENGINEERING
UNIVERSITY OF PETROLEUM AND ENERGY STUDIES

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ACKNOWLEDGEMENT
Industrial training was an indispensable part of any engineering curriculum. It provides
the students an opportunity to gain experience about the practical applications of their
knowledge.
My training at MARUTI SUZUKI INDIA LIMITED, GURGAON has been very
fruitful. I am sure that the hands-on experience I have gained here will go a long way
towards making me a competentengineer.
I would like to convey my sincere gratitude to Mr. Madhav Uniyal (Senior Manager,
QAPQ G3) my project guide who trusted me and gave me responsible project work and
provided me with timely and proper guidance whenever required. This provided me
experience in not only the technical and practical aspects of the industry but also in
human relations, teamwork and also provided great insights into the actual working of an
industry. Without his efforts, this training would not have been as great a learning
experience as it has been.
I would also like to thank Mr. Jony Khandelwal (Deputy Manager), Mr. Ritesh
Mishra (Assistant Manager) for giving me the opportunity to work in their department.
I take this opportunity to also thank the other members of QAPQ department who offered
their unconditional support and advice during the course of my training.

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TABLE OF CONTENTS
S.No. Contents Page No
1. INTRODUCTION TO COMPANY 5
2. COMPANY PROFILE 6
3. MANUFACTURING FACILITIES 6
4. QUALITY TOOLS AT MSIL 7
5. SAFETY MEASURES AT MSIL 8
6. MARUTISUZUKI CAR PLANT OWERVIEW 9
7. DEPARTMENT ALLOCATED AT MSIL 11
8. PPAP 12
9. QMAC THE 7 BASIC TOOLS 13
10.THINGS LEARNED AT MARUTI SUZUKI 16
11.PROJECT ASSIGNED – AOI 21
12.DEFECTS IN A PCB 22
13.DEFECT DETECTION IN A PCB 25
14.AUTOMATED OPTICAL INSPECTION 26
15.AOI IMAGE CAPTURE ANALYSIS 27
16.AOI LIGHT SOURCE 27
17.AOI IMAGING SYSTEM 28
18.AOI PLATFORMS 29
19.COMPAIRING 2D AND 3D AOI 30
20.COMBINING 2D AND 3D AOI 30

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TABLE OF FIGURES
THIS REPORT DOES NOT CONTAIN ANY IMAGES BECAUSE WE
WERE NOT ALLOWED TO CLICK PHOTOS OR TRANSFER ANY
SORT OF MATERIAL FROM THEIR SYSTEMS. THEREFORE TO
MAINTAIN A PROPER DECORUM I HAVENT USED ANY IMAGES OR
FIGURES IN THIS REPORT.

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INTRODUCTION TO COMPANY
Maruti Suzuki India Limited, formerly known as Maruti Udyog Limited, is an automobile
manufacturer in India. It is a subsidiary of Japanese automobile and motorcycle manufacturer
Suzuki Motor Corporation.
Maruti Udyog Limited was established in February 1981, though the actual production
commenced only in 1983. It started with the Maruti 800, based on the Suzuki. Originally, 74%
of the company was owned by the Indian government, and 26% by Suzuki of Japan. As of May
2007, the government of India sold its complete share to Indian financial institutions and no
longer has any stake in Maruti Suzuki India Limited. As of November 2012, it had a market
share of 50% of the Indian passenger car markets. Maruti Suzuki manufactures and sells
popular cars such as the Alto, Celerio, Ignis, WagonR, Swift, Baleno, Ertiga, Swift Dzire, Ciaz,
Vitara Brezza, S-Cross, Ecco, Carry, Jeep and Omni. The company is headquartered at New
Delhi. In February 2012, the company sold its ten-millionth vehicles in India.
MSIL is currently owned in majority by Suzuki (56%) while the remaining ownership is listed
publicly (44%). Its highest service outlet in Kaza – Spiti Motors – is at an altitude of 12,270 ft.
and the company also operates a service outlet in the Andamans.
MSIL started exporting vehicles as early as 1987 – some of the cars you will see on the
assembly line are LHD – and a majority of the vehicles (41%) go to Europe. Asia accounts for
22% of exports which is stated to rise given that the company has begun Ciaz exports to Japan.
Latin America accounts for 18% of the volume, Africa 8% and Oceania (Australia and New
Zealand) accounts for 2%.
The company has established a large presence around the NCR region, with a head office in
Vasant Kunj, New Delhi supported by two plants in Gurgaon and Manesar, and an R&D
facility in Rohtak.
Maruti Suzuki Becomes First Automaker In India To Produce 2 Crore Cars
India’s largest car manufacturer, Maruti Suzuki India Limited added yet another feather to its
cap. It has now become the only carmaker to have produced a total of 2 crore cars in India. The
company representatives, including Kenichi Ayukawa, MD and CEO of MSIL, celebrated the
rollout of the 20 millionth Maruti car, a Vitara Brezza, at the company’s Gurugram plant.

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COMPANY PROFILE
The chairman of Maruti Suzuki India Ltd. is RC Bhargava, who is awarded by Padma Bhushan
award. The first car is launched on 14th December 1983 by Indira Gandhi. The first car was
Maruti 800 and sold at a price of 47,500Rs. Maruti Suzuki has two manufacturing facilities in
India. Both manufacturing facilities have a combined production capacity of 14,50,000
vehicles annually. The Gurgaon manufacturing facility has three fully integrated manufacturing
plants and is spread over 300 acres (1.2 km2). The Gurgaon facilities also manufactures
240,000 K-Series engines annually. The Manesar manufacturing plant was inaugurated in
February 2007 and is spread over 600 acres (2.4 km2). Initially, it had a production capacity of
100,000 vehicles annually but this was increased to 300,000 vehicles annually in October 2008.
The production capacity was further increased by 250,000 Vehicles taking total production
capacity to 800,000 vehicles annually.
MANUFACTURING FACILITIES
Maruti Suzuki has two manufacturing facilities in India. Both manufacturing facilities have a
combined production capacity of 1,450,000 vehicles annually.
GURGAON PLANT
The Gurgaon manufacturing facility has three fully integrated manufacturing plants and is
spread over 300 acres. All three plants have an installed capacity of 350,000 vehicles annually
but productivity improvements have enabled it to manufacture 1,000,000 vehicles annually.
The Gurgaon facilities also manufacture 250,000 K-Series engines annually. The entire facility
is equipped with more than 150 robots, out of which 71 have been developed in-house. The
Gurgaon facility manufactures Ignis, WagonR, Omni, Gypsy, S-Cross, Brezza and Eeco.
MANESAR PLANT
The Manesar manufacturing plant was inaugurated in February 2007 and is spread over 600
acres. Initially, it had a production capacity of 100,000 vehicles annually but this was increased
to 300,000 vehicles annually in October 2008. The production capacity was further increased
by 250,000 vehicles taking the total production capacity to 550,000 vehicles annually. The
Manesar Plant produces the Swift, Baleno, Swift Dzire, Ciaz, Alto K10.

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QUALITY TOOLS AT MSIL
To maintain international standards, the Japanese have evolved certain standard quality
statements, which are strictly adhered to in the production process. The quality tools used by
Suzuki culture are:
THE 5-S
• Seiri - Proper Selection
• Seiton - Arrangement
• Seiso - Cleaning
• Sheiketsu - Cleanliness
• Shitsuke - Discipline
THE 3-K
• Kimerareta Koto Ga - What has been decided
• Kihin Doro - as per standard
• Kichin To Momoru - must be followed
THE 3-G
• Genchi - Actual Place
• Genbutsu - Actual Thing
• Genjitsu - Actually
THE 3-M (Problems affecting production)
• Muri - Inconvenience
• Mura - Wastage
• Muda - Inconsistency

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SAFETY MEASURES AT MSIL
In MSIL safety measures are taken as at most priorities for the smooth and unhampered
running of the company so as to meet the targeted volume of production. Classes are taken on a
regular basis for the repairmen to realize the importance of safety measures .Safety measures
mainly include PPEs (Personal Protective Equipment) which encourages the use of the
following equipment:
1. Helmet/Cap - Precaution against Head Injury
2. Mouth mask - Precaution against Dust, Fume, and sand.
3. Shoes - Precaution against Leg Injury
4. Harness belt - Precaution against Falling down from a height
5. Glasses - Precaution against Dents
6. Garments - Precaution against Sparks, Dirt and, Paint
7. Gloves - Precaution against cuts and wounds
8. Ear buds - Precaution against damage to ears due to the high- intensity sound of
machines.

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MARUTI SUZUKI CAR PLANT OVERVIEW
The making of a car starts from the press shop, where the raw material is obtained in the form
of cold- rolled sheets. From the press shop, the parts are send to the weld shop, where they are
welded to make the frame of the car. From the weld shop, these frames are transferred via
conveyors to the paint shop, where these are coated and glazed. From the paint shop, these are
send to the assembly shop, where through a conveyor system, various parts are fitted at various
canopies or stations. The machine shop and the engine assembly shops are located close to the
respective assemblies, and the car engine and other transmission parts are also fitted in the
assembly shop itself. Then, the V I department conducts various tests to ensure that no defects
remain before the car is dispatched via trucks to various parts of the country.
PRESS SHOP
This process involves cutting and stamping metal sheets into the shape of body panels using
heavy duty stamping machines and dies.
 Coils of raw material are received from suppliers, and they are cut and blanked into
sheets of metal as per the requirement of different body panels.
 The panels are then loaded into the stamping machine.
 Suction cups raise the panels into position, and then the die stamps the panels
into shape.
 A body panel exits the stamping machine every six seconds. The machines are capable
of producing similar panels (e.g. left and right door) or dissimilar panels (e.g. outer
hood and inner hood panels) simultaneously in a single stroke, reducing the need for
manual intervention.
 Interestingly, the excess material exits the line from the side. These panels are reused to
make other components, reducing wastage and thereby increasing yield on the material.
 There is no manual intervention during the stamping process. Panels are checked at
regular intervals for quality control and compliance with defined tolerances.
 The finished panels are then transferred to the weld shop.

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WELD SHOP
The finished panels from the press shop come together to form a car body frame in the weld
shop. Think of all four doors, the hood, the trunk, roof, floor and the frame panels coming
together to be welded and form a single car shell. The shop is 100% automated, and it is
fascinating to see the huge robots work in sync, programmed to perfection as they finish one
weld spot after another seemingly as if they were alive. The weld line does not have any
workers operating machines or the panels, just some overseeing and supervising the process for
compliance. The machines are sensor based, and read the PSN (production sequence number)
to recognize the model and correspondingly the job at hand, and they weld spots accordingly.
PAINT SHOP
Once the shell of the car takes life, it’s time to put some paint on it. This actually involves
several processes and coats: Pre-treatment (cleaning for the next process), Electro deposition
(for corrosion resistance), Sol-Sealing and Undercoat, Top Coat Paint (base coat and clear
coat), and Inspection. These layers ensure that the paint sprays onto the body efficiently and
evenly, and the sheen of the paint is seen once the operation is completed. Each of these coats
can be measured in microns and is very fine. Once the panels are painted, they are closely
inspected under light for any imperfections and blemishes. These are rectified immediately,
and the body is then sent to the assembly line where all the interior and exterior fittings take
place.
ASSEMBLY LINE
The final assembly shop is where all the components come together in sequence to form the
cars as we see them on the showroom floor.

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DEPARTMENT ALLOCATED DURING INDUSTRIAL TRAINING
Quality Assurance and Part Quality (QAPQ-G3) Understanding QAPQ-G3
This department as the name suggests is responsible for maintaining the quality of the products
sold in the market by MSIL. This involves both, the cars made by MSIL as well as the genuine
spare parts sold in the market.
The quality department thus ensures quality at the vendor end and conducts various visits for
inspection. Main tasks performed are new model development, line issues validation, change
management, revalidation, SMIR- Suzuki Maruti Inspection Report.
There is a record of documents commonly known in the industry as PPAP documents which
have details of the part which the file is of. This record is made whenever a new component
has to be used on the production line be it for a new vehicle or for a change of a particular part
in the existing vehicle.
During a visit to the vendor, it is made sure that the vendor is producing the components
according to the specifications and standards mentioned in the PPAP documents.
Popular Vendors of Maruti Suzuki India Limited
• DENSO (Gurgaon, Manesar, Jhajjhar – Relay, Speedometer, Wiper Motors etc.)
• MINDA FURUKAWA (Noida, Bawal – Wiring Harness)
• MOTHERSON SUMI INDIA LTD. (Gurgaon, Noida – Wiring Harness)
• APTIV (Manesar – Body Control Module)
• NIPPON AUDIOTRONIX (Noida – Audio Systems, RPAS System)
• MISTUBISHI (Manesar – Electronic Parts)
• BOSCH (Noida, Gurgaon – Oil Pumps, Sensors, Electronic Parts)
• BHARAT SEATS (Gurgaon, Okhla - Seats)
• MAHLE (Manesar, Parwanu – Oil Filters)
• COOPER STANDARD (Gurgaon – Sealing Systems )
• BONY POLYMERS (Faridabad – Hoses, Plastic Parts )
• SUBROS (Manesar - Compressors)
PRODUCTION PART APPROVAL PROCESS (PPAP)
Purpose of PPAP
The purpose of PPAP is to determine that all customer engineering design record and
specification requirements are properly understood by the organization and that the
manufacturing process has the potential to produce product consistently meeting these
requirements during an actual production run at the quoted production rate.

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Applicability of PPAP
PPAP is applicable under following conditions
• New part or product (e.g. a specific part, material, or colour not previously supplied to the
specific customer)
• Product modified by an engineering change to design records, specifications, or materials.
• Change in location, subcontractor, material, etc.
• Correction of a discrepancy on a previously submitted part.
• Any situation required (Customer notification and submission requirement)
PPAP Processes Requirement
• Significant Production Run
For production parts, This significant production run shall be from one hour to eight
hours of production, and with the specific production quantity to total a minimum of 300
consecutive parts, unless otherwise specified by the authorized customer representative.
This significant production run shall be conducted at the production site, at the production
rate using the production tooling, production gaging, production process, production
materials, and production operators. Parts from each unique production process. For bulk
materials: No specific number of "parts" is required. The submitted sample shall be taken in a
manner as to assure that it represents "steady-state" operation of the process.
• PPAP Requirements
The organization shall meet all specified PPAP requirements listed below the organization
shall also meet all customer-specific PPAP requirements (Engineering design record and
specification requirements including safety and regulatory requirements).
If any part specifications cannot be met, the organization shall document their problem-solving
efforts and shall contact the authorized customer representative for concurrence in
determination of appropriate corrective action.
1. Design Record
2. Authorized Engineering Change documents
3. Customer Engineering Approval
4. Design Failure Mode and Effects Analysis (Design FMEA)
5. Process Flow Diagram(s)
6. Process Failure Mode and Effects Analysis (Process FMEA)
7. Control Plan
8. Measurement System Analysis Studies
9. Dimensional Results
10. Records of Material/ Performance Test Results
11. Initial Process studies
12. Qualified Laboratory Documentation
13. Appearance Approval Report (AAR)
14. Sample Production Parts
15. Master Sample
16. Checking Aids
17. Customer-Specific Requirements
18. Part Submission Warrant (PSW)

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Quality - Management and Control, the 7 basic tools used
Managing quality is crucial for businesses. Quality products help to maintain customer
satisfaction and loyalty and reduce the risk and cost of replacing faulty goods. Quality
improvement is a continuous process. The tools of Quality are used company – wide for
advancement in total quality management. These are the basic techniques useful in solving
problem concerning quality, cost, production volumes that arise in the workplace logically and
effectively.
The basic 7 Tools of Quality are –
• Histograms
• Pareto charts
• Cause and effect diagrams
• Check sheets
• Scatter diagrams
• Flow charts
• Control charts
HISTOGRAMS
Histograms are a graphical representation of data in a bar chart format used to observe the
“shape” of the data. They can also be used to show the relationships of many different
collections of data including any process that requires random samples to determine if the
process is performing properly.
Some rules for developing histograms
• The width of the histogram must be consistent.
• The classes must be mutually exclusive and all inclusive.
• The number of the classes is decided by 2^k >=n where n is the number of data values
and k is the number of classes.
PARETO CHARTS
Pareto charts identify and prioritize problems that need to be solved. They can also be used for
a variety of analyses. For example: identifying and prioritizing complaints from customers,
store inventory and distribution of wealth among countries.
Some rules for developing pareto charts
• Information must be selected based on types of defects that occur as a result of a
process.
• Data must be collected and categorized.
• A histogram or frequency chart is constructed showing the number of occurrences.
CAUSE AND EFFECT OR THE FISHBONE OR THE ISHIKAWA DIAGRAM
These diagrams look like the skeleton of a fish, with the problem being the head and the causes
being the head and the causes being the “ribs” and the sub-causes being the smaller “bones”
stemming from the ribs. They are used as an abstract way to depict the causes and effects of the
major problems in the process. For example – causes of delayed flight departures,
broken/faulty products, late product delivery.
Steps in creating a fishbone diagram or cause and effect diagrams
• State the problem directly in the head of the fish.
• Draw the backbone and ribs.
• Continue to fill out the diagram asking, “Why?” about each cause of the problem.
• View the diagram and identify the core causes.
• Set goals to address the core causes.

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CHECK SHEETS
Check sheets are data gathering tools that can be used in forming histograms and pareto charts.
These are a form used to record the frequency of occurrences of certain product or service
characteristics related to quality. These can be either tabular or schematic. Examples of when
check sheets may be helpful: tracking customer complaints at a restaurant, slow production
times, faulty/defective products.
Steps in designing a check sheet
• Identify common defects occurring in the process.
• Draw a table.
• The user places check marks on the sheet when a defect is encountered.
SCATTER DIAGRAMS
Scatter diagram is used to examine the relationships between variables. They are also used to
investigate the possible relationship between two variables that both relate to the same “event”.
A straight line of best fit (using the least square method) is often included. Examples of when
scatter diagrams can be used to determine if there is a relationship: prevention costs and
conformance, overtime hours versus days absent, determining if a particular defect is due to
run size.
Steps in setting up a scatter plot
• Determining the X (independent) and Y (dependent) variables.
• Gather process data relating to the variables identified in step above.
• Plot the data.
• Observe the plotted data to see if there is a relationship between the variables.
FLOWCHARTS
A flowchart is a graphical representation of a process. The first step in many process
improvement projects is to create a flowchart. An example of a process that could use a
flowchart would be a restaurant. When a customer enters the restaurant, if there is a table
available they are seated. If not, they can wait or sit at the bar and have a drink. When the table
becomes available, the customer is seated. After eating, the patron pays for the food or can
either leave or sit at the bar.
Symbols used in Flow Charts
• Oval: Denotes the beginning or end of a program.
• Flow line (arrow): Denotes the direction of logic flow in a program.
• Parallelogram: Denotes either an input operation or an output operation.
• Rectangle: Denotes a process to be carried out.
• Diamond: Denotes a decision (or branch) to be made. The program should continue
along one of two routes.
Steps in creating a flow chart
• Develop a general process and then fill in the elements of the process.
• Observe the people doing the process.
• Determine which steps add value and which do not, to simplify work.
• Determine whether the work actually needs to be done.

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CONTROL CHARTS
A control chart is used to determine whether a process will produce a product or service with
consistent measurable properties. A control chart has a nominal value or central line and an
upper and lower control limit. Example of when to use control charts: quality inspection and
checking for defects in products.
Steps in forming a control chart
• Take a random sample from the process, measure the quality characteristics and
calculate a variable or attribute measure.
• If the statistic falls outside the control limits, then look for assignable causes.
• Either eliminate or incorporate the cause. Reconstruct the control chart with the new
data.
Things learned at Maruti Suzuki India Limited
Tyre Care and Management
Most of us operate motor vehicles on daily basis and hardly ever pay any attention to one of the
most vital parts of the vehicle which are our tyres.
There are certain things that you need to know about tyres-
 Expiration Date - Tyre expire 4 years after the date of manufacture and this date is
stamped on the side of the tyre. If we use expired tyres, they are likely to burst and
result in a very serious or even a fatal accident.
 Size Index – The size index is a code mentioned on the side of the tyre which tells you
about the specification of the tyres.
For example - P 265 / 60 R 18
P – Passenger Car Tyre
265 – Tyre Width in mm
60 – Aspect Ratio (Height to Width ratio of tire, 60% of width in this case)
R – Radial Tyre
18 – 18 Inch Wheel
 Pressure Index – On the side of the tyre, you will also find the maximum allowable
inflating pressure for that specific tyre, some tyres have a maximum pressure of 32 psi
some are rated at 44psi and some even 50 psi. Check your specific tyre to see what the
maximum pressure is for your tyres, it is an acceptable practice to have your tyres a few
pounds below maximum allowable pressure but not too much.
 Load Index – Also mentioned on the side of the tyre, the load index tells you about the
maximum load which should be applied on the tyre. For example 109T means
maximum load capacity 2271 lbs 1030 kg.
 Speed Index – The speed rating for which a tire is indicated by a letter next to the load
index.
 Temperature Index – This is another code mentioned which indicates a tyre resistance

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to heat. Tyres are rated from highest to lowest resistance as A, B or C.
 Traction Index – Traction is the tyres ability to stop on wet pavement. A higher graded
tyre should allow you to stop your vehicle on a wet road in a shorter distance than a tyre
with lower grade. Traction is graded from highest to lowest as AA, A, B or C.
 Tread Wear Index – This number will give you the rate at which the tire wears out, the
higher the tread wear the longer it should take for the tire to wear out.
Factors affecting tyre performance –
 Tyre Pressure - Lower pressure increases tyre heat at higher speeds and excessive heat
results in tire damage.
 Vehicle Loading – Many times we overload our vehicles without paying any attention
to the strain this puts on our tires, exceeding the maximum load rating on a tire may
also lead to tyre failure.
 Aspect Ratio – Aspect Ratio = Height / Width
Lesser the aspect ratio more is the traction and hence the cost increases.
 Rolling Resistance – It is the effort required to keep your tyre rolling. Low rolling
resistance tyres helps in less fuel consumption.
 Wheel Alignment Parameters (Toe, Camber, Caster) – Tire alignment helps your tyre
perform properly and last longer. Having tyres aligned and balanced every 5,000 to
6,000 miles can help maximize their lifespan and overall performance.
Turbocharger
Turbocharger is a mechanical device that is used to increase the power and efficiency of an
engine by increasing the amount of air entering into the combustion chamber. More air into the
combustion chamber means more amount of fuel will be fed into the cylinder and as a result
one will get more power from the same engine if a turbocharger is installed in it.
A turbocharger basically draws the air from the atmosphere and compresses it with the help of
a compressor before it enters into the intake manifold at increased pressure. This results in
more amount of air entering into the cylinders on each intake stroke. The compressor gets
power from the kinetic energy of engine’s exhaust gases.
A turbocharger has three main components
1. A turbine (radial inflow turbine)
2. A compressor (centrifugal compressor)
3. The centre hub rotating assembly
How a turbocharger works
1. Cool air enters the engine's air intake manifold and heads toward the compressor.
2. The compressor fan helps to suck air in.

17. 17
3. The compressor squeezes and heats up the incoming air and blows it out again.
4. Hot compressed air from the compressor passes through the heat exchanger, which
cools it down.
5. Cooled compressed air enters the cylinder's air intake manifold. The extra oxygen helps
to burn fuel in the cylinder at a faster rate.
6. Since the cylinder burns more fuel, it produces energy more quickly and can send more
power to the wheels.
7. Waste gas from the cylinder exits through the exhaust outlet.
8. The hot exhaust gases blowing past the turbine fan make it rotate at high speed.
9. The spinning turbine is mounted on the same shaft as the compressor. So, as the turbine
spins, the compressor spins too.
10. The exhaust gas leaves the car, wasting less energy than it would otherwise.
Turbochargers can be used with either petrol or diesel engines. An engine fitted with a
turbocharger is much smaller and lighter than an engine producing the same power without a
turbocharger, so a turbocharger car can give a better fuel economy.
Maruti Suzuki Ciaz the most fuel efficient Sedan
Regenerative braking
Suzuki’s new SHVS system works on the principle of regenerative braking. The regenerative
braking system is an advanced braking system that is used along with the conventional braking
system in hybrid vehicles. The conventional braking causes friction between brake pads and
disc. It converts vehicle's kinetic energy into heat, which goes wasted. However, the
regenerative system recovers some of the waste energy and puts it to use again. The system
converts this waste energy into electricity. The electricity, saved charges the battery of
the vehicle. The system consists of an electric motor with dual function. It works as a motor, in
one direction and also as a generator, in the opposite direction. While braking the motor runs in
the opposite direction and becomes an electric generator. The Ciaz comes with a bigger lead
acid battery in the SHVS model.
Integrated Starter Generator
Also referred as an ISG, Integrated Starter Generator allows the hybrid vehicle’s engine to
instantly and quietly restart after the idle stop, when the engine shuts down to save fuel and
emissions. Like an alternator, the ISG produces electric power when the vehicle is running,
which is used to supply electric devices and/or to charge the battery. The ISG can help to
decelerate the vehicle by generating electric power, which is called regenerative braking. The
electric power generated charges the battery, reducing fuel consumption. If a clutch
disconnects the ISG and the compressor from the engine during the idle stop, the ISG can drive
the air-conditioning compressor via a belt. And since the ISG motor aids the Ciaz mild hybrid
in acceleration with electricity, the engine does not have to rev as much when the car
accelerates thereby saving fuel.
Idle Start/Stop
Maruti proves to be the best when it comes to squeezing out mileage from its cars and this
technology takes it a step forward. The Maruti Ciaz mild hybrid also comes with idle start/stop

18. 18
technology that shuts off the engine when the car comes to a halt in order to save fuel in
stop/start traffic conditions. The high capacity battery supplies power to the ISG which is
connected to the engine via belt (for smooth operation). The engine has a start-stop feature
which automatically turns it off when you come to a stop, put the car in neutral and take your
foot off the clutch. The engine restarts as soon as you press the clutch.
Power Assist
The Ciaz is fitted with high capacity batteries providing power to the ISG which in turn boosts
the engine performance, taking load off the diesel motor at the time of acceleration. This
results in better power delivery and less fuel consumption.
Gear Shift Indicator
Like all shift indicators this works the same way, informing the driver to shift at the optimum
speed and revs to get better fuel economy.
BCM – Body Control Module
In automotive electronics, body control module is a term used for an electronic control
unit responsible for monitoring and controlling various electronic accessories in a vehicle's
body. The BCM communicates with other on-board computers via the car's vehicle bus, and its
main application is controlling load drivers – actuating relays that in turn perform actions in the
vehicle such as locking the doors or dimming the salon overhead lamp.
The functions performed by bcm are
 Power door lock
 Trunk lid open
 Fuel lid
 Clearance light (Indicators)
 Headlight
 Fog lights
 DRL- Daytime Running Lamp
 Turn Signal light
 Interior light
 Wipers
 Rear defogger
 Shift lock
 Seat belt reminder
 Warning buzzer

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Engine Control Unit
An engine control unit (ECU), also commonly called an engine control module (ECM), is a
type of electronic control unit that controls a series of actuators on an internal combustion
engine to ensure optimal engine performance. It does this by reading values from a multitude
of sensors within the engine bay, interpreting the data using multidimensional performance
maps (called lookup tables), and adjusting the engine actuators. Before ECUs, air-fuel mixture,
ignition timing, and idle speed were mechanically set and dynamically controlled
by mechanical and pneumatic means.
If the ECU has control over the fuel lines, then it is referred to as an Electronic Engine
Management System (EEMS). The fuel injection system has the major role to control the
engine's fuel supply. The whole mechanism of the EEMS is controlled by a stack of sensors
and actuators.
Various Sensors used in the Engine
Camshaft Position Sensor
The camshaft sensor enables the engine control to determine the exact position of the
crankshaft drive. This information is required to calculate the ignition point and injection point,
among other things. On this page, you can find out how a fault on the camshaft sensor can
manifest itself, and which steps should be taken during troubleshooting.
The task of the camshaft sensor is to work with the crankshaft sensor to define the exact
position of the crankshaft drive. Through the combination of both sensor signals, the engine
control unit knows when the first cylinder is in the top dead point.
This information is needed for three purposes:
1. For the start of injection during sequential injection.
2. For the actuation signal of the solenoid valve for the pump-nozzle injection system.
3. For cylinder-selective knocking control.
The camshaft sensor works according to the Hall principle. It scans a ring gear on the camshaft.
The rotation of the ring gear changes the Hall voltage of the Hall IC in the sensor head. This
change in voltage is transmitted to the control unit and evaluated there in order to establish the
required data.
Crankshaft Position Sensor
The crankshaft sensor is one of the key providers of information of the engine control. It
detects the speed and position of the crankshaft and forwards this information to the engine
control in the form of an electrical signal. On this page, you can find out how crankshaft
sensors work, and what must be taken into account when checking them in order to prevent
damage.

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The function of crankshaft sensors is to measure the crankshaft's speed and position. They are
most commonly installed near to the flywheel ring gear. There are two designs: Inductive
sensors and Hall generators. Before the crankshaft sensor is tested, it is essential to know
which type of transmitter is involved.
The rotary movement of the ring gear results in changes to the magnetic field. These generate
varying voltage signals in the crankshaft sensor, which are transmitted to the control unit. The
control unit uses the signals to calculate speed and position of the crankshaft in order to gain
important basic data for injection and ignition timing.
Vehicle Speed Sensor
The Vehicle Speed Sensor (VSS) is a part of your vehicle's ant-lock braking system (ABS). In
addition the output from the VSS is also used for the odometer to read the vehicle's speed and
for your vehicle's automatic transmission to switch gears according to the speed of your
vehicle. The ABS is a vehicle safety mechanism that maintains the vehicle's tractive contact
with the road during braking. The engine control unit (ECU) works in conjunction with a
number of sensors and hydraulic valves to control the braking action. The ECU needs to
constantly monitor the speed of the wheels in order to kick the braking system into action when
needed.
The sensor is essentially a tachometer device that measures the transmission or transaxle speed
and sends the information to the ECU. The VSS has a toothed ring and a voltage generator.
The voltage generator generates a constant voltage in between its own permanent magnet and
coil. This constant voltage is disrupted periodically by the rotating teeth of the ring to generate
a pulse output which is sent to the ECU for interpretation of the speed of the vehicle.
Throttle Position Sensor
The throttle position sensor (TPS) is part of your vehicle's fuel management system, and helps
ensure that the correct mixture of air and fuel is delivered to your engine. The TPS provides the
most direct signal to the fuel injection system of what power demands are being made by the
engine. The TPS signal is continually measured and combined many times per second with
other data such as air temperature, engine RPM, air mass flow, and how quickly the throttle
position changes. These data determine precisely how much fuel to inject into the engine at any
given moment. If the throttle position sensor and its other sensor partners do their job correctly,
your car accelerates, cruises, or coasts smoothly and efficiently, as you expect, while
maintaining optimal fuel economy.

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PROJECT ASSIGNED – Automated Optical Inspection (AOI)
PCBA (Printed Circuit Board Technology)
PCBA is a segment of printed circuit board technology. The segment of printed circuit board
industry is concentrated in assembling all the pieces of electronic industry to one piece before
output them to the market. This segment covers interconnection technology, package design
technology, system integration technology, board and system test technology etc. However, in
a very brief and short description, PCBA is the segment that concentrated in assembly of all
electronics and electromechanical components on the surface of a PCB using metallic bonding
such as pin through hole solder, surface mount solder or press fit interconnection.
Pin Through Hole Technology
Pin through hole is a technology where components are soldered on the board using male-
female type connections. PCB bare fabrication will provide holes holes that connected to all the
internal circuits of the fabrication. On the other hand the components that will be assembled on
this through hole fabrication and then solder them together by selective wave, selective wave
fixture or dip in the liquid solder to form interconnection joints.
SMT- Surface Mount Technology
The current and widely used technology now is SMT. Mounting or soldering the components
on PCB surface is SMT. Difference between SMT and pin through hole technology is that pin
through uses liquid solder whereas SMT uses solder in the physical form of paste and then melt
this paste in a heat oven to form the solder joint.
Processes involved in speedo SMT lines of different suppliers
1. Bare PCB loading in racks
2. PCB brush cleaning and roller cleaning
3. Stencil Placement on PCB
4. Solder paste printing
5. SMT component mounting
6. Large components mounting
7. Reflow oven
8. AOI- Automated Optical Inspection
9. ROBO soldering
10. PCB routing
11. QFP inspection
12. ICT – In circuit testing
13. FCT – Functional circuit testing

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Defects in a PCB
Pin Holes & Blow Holes on a Printed Circuit Board
Caused by the printed board outgassing during soldering. Pin and blow hole formation during
wave soldering is normally always associated with thickness of copper plating. Moisture in
the board escapes through either thin copper plating or voids in the plating.
Bulbous Joint / Excess Fillet
A solder joint on chip components that is over the height of the part with a convex meniscus
is referred to as bulbous or excess fillet. It is caused during separation of the board from the
solder wave and is more common in nitrogen soldering.
Lifted Component
Lifted components can occur during wave soldering for a number of reasons. Simply by
increasing the immersion time in the wave eliminated the problem. Generally components lift
due to: Incorrect lead length causing the leads to hit the solder bath and lift during entry to
the wave. Components with either different thermal demands or different lead solderability
can also cause the lifting.
Flux Residues
Flux residues visible on the board are more common due to the reduction in the use of
cleaning in the industry. Over 75% of companies in Europe use no clean low residue
materials. With the reliability of no clean being demonstrated in automotive products, the
number of cleaning processes will continue to decline.
Incomplete Joints
The incomplete solder fillet is often seen on single-sided boards after wave soldering.This
reduces the drainage performance of the wave but can lead to the incidence of shorting.
Reducing wave temperature has also been seen to overcome the problem.

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Inconsistent or Poor Hole Fill
This is a common problem seen when a company changes over from a foam fluxer to a spray
flux unit; it is due to the poor penetration of flux into the through hole.
Lifted Pads
Lifted pads are rarely seen on plated through hole boards but can occur on single-sided
boards during assembly. Care needs to be taken when lifting boards from the conveyor or out
of pallets as often large components are often used by operators as handles.
Lifted Resist
It is caused due to incorrect specification of the printed board. Tin/lead should not be used
under resist on professional circuit boards. As the tin/lead moves into a liquid phase it
expands and may cause loss of adhesion between the solder and the resist.
Outgassing
Outgassing is a common problem associated with wave and hand soldering. Basically when a
board is soldered any moisture in the board close to the hole is heated and turned to vapour.
If there is thin plating or voids in the plating, gassing can come through the plated hole wall.
If solder is present in the hole, this will produce voids in the solder as it solidifies.
Solder Flags
Solder flags or spikes are due either to inconsistent flux application or poor control of solder
drainage from the wave. Poor control of separation from the solder wave would tends to be a
random fault, not on the same contacts every time. The solder should flow at the same speed
and direction as the board during separation from the wave.
Solder Shorts
Solder shorts are generally on the increase in the wave soldering process. This is due to the
ever decreasing component pitches used in manufacture. Solder shorting occurs when the
solder does not separate from two or more leads before the solder solidifies. Increasing the
flux solids or quantity is one way of decreasing shorting.

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Solder Skips
Unsoldered surface mount joints are referred to as solder skips where the termination does
not have any solder. It is caused by incorrect chip wave height or gassing of the flux on the
underside of the board.
Sunken Joints
Sunken joints on the base of the board are most commonly caused by outgassing from the
printed board. Like small voids in the solder fillets, they are seen as another process
indicator.
Solder Mask Discoloration
Normally this is a cosmetic issue but should be investigated for the real cause. When running
a thicker board it is probable that the soldering process or dwell times may have changed.
Defect detection in a PCB
Despite the major improvements that have been made, modern circuits are far more
complicated than boards were even a few years ago. The introduction of surface mount
technology, and the subsequent further reductions in size mean that boards are particularly
compact. Even relatively average boards have thousands of soldered joints, and these are where
the majority of problems are found.
This increase in the complexity of boards also means that manual inspection is not a viable
option these days. Even when it was an accepted approach, it was realised that it was not
particularly effective as inspectors soon tired and poor and incorrect construction was easily
missed. With the marketplace now requiring high volume, high quality products to be brought
to market very quickly very reliable and fast methods are needed to ensure that product quality
remains high. AOI, automatic optical inspection is an essential tool in an integrated electronics
test strategy that ensure costs are kept as low as possible by detecting faults early in the
production line.
AOI, Automated Optical Inspection
AOI, automated optical inspection is an automated vision inspection of PCB during the
manufacturing process. It is used to scan the inner layers and outer layers of PCB after the
processes of etching and stripping. After scanning by AOI machine, the defects which do not
meet the manufacturer’s requirement will be identified by the machine. In this way, AOI can
detect problems early in the production process, so faults would not be passed to next
production process and production cost could be saved. AOI uses visual methods to monitor
printed circuit boards for defects. They are able to detect a variety of surface feature defects

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such as nodules, scratches and stains as well as the more familiar dimensional defects such as
open circuits, shorts and thinning of the solder. They can also detect incorrect components,
missing components and incorrectly placed components. As such they are able to perform all
the visual checks performed previously by manual operators, and far more swiftly and
accurately.
They achieve this by visually scanning the surface of the board. The board is light by several
light sources and one or more high definition cameras are used. In this way the AOI machine is
able to build up a picture of the board. The AOI system uses the captured image which is
processed and then compared with the knowledge the machine has of what the board should
look like. Using this comparison the AOI system is able to detect and highlight any defects or
suspect areas.
AOI uses a number of techniques to provide the analysis of whether a board is satisfactory or
has any defects:
 Template matching: Using this form of process the AOI, automated optical inspection
system compares the image obtained with the image from a "golden board".
 Pattern matching: Using this techniques the AOI system stores information of both good
and bad PCB assemblies, matching the obtained image to these.
 Statistical pattern matching: This approach is very similar to that above, except that it uses
a statistically based method of addressing problems. By storing the results of several boards
and several types of failure, it is able to accommodate minor acceptable deviations without
flagging errors.
As technology has improved it has been able for AOI systems to very accurately predict defects
and have a small number of no defect found scenarios. As such AOI systems form a very
useful element in a sophisticated manufacturing environment.
AOI image capture and analysis
One of the key elements of an AOI, automated optical inspection system is the image capture
system. This captures an image of the printed circuit board, PCB assembly which is then
analyzed by the processing software within the AOI system. There are many variants of image
capture system dependent upon the exact application and the complexity / cost of the AOI
system.
Imaging systems may comprise a single camera or there may be more than one to provide
better imaging and the possibility of a 3D capability. The cameras should also be able to move
under software control. This will enable them to move to the optimum position for a given PCB
assembly.
In addition to this the type of camera has an impact on performance. Speed against accuracy is
a balance that has to be struck and will impact on the camera type used:
 Streaming video: One type of camera used for automated optical inspection, AOI, takes
streaming video from which complete frames are taken. The captured frame then enables a
still image to be generated on which the signal processing is performed. This approach is
not as accurate as other still image systems but has the advantage of very high speed.

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 Still image camera system: This is generally placed relatively close to the target PCB and
as a result it requires a good lighting system. It may also be necessary to be able to move the
camera under software control.
When analyzing an image of a board, the AOI system looks for a variety of specific features:
component placement, component size, board fiducially, label patterns (e.g. bar codes),
background colour and reflectivity, etc. As an important element of its task the AOI system
also inspects the soldered joints to ensure they indicate that the joints are satisfactory.
When analyzing the boards the AOI system must take into account many variations between
good boards. Not only do components vary considerably in size between batches, but also the
colour and reflectivity. Often there are also differences in the silk screening where ink
thickness and colour typeface may change slightly.
AOI Light Source
Lighting is a key element in the AOI system. By choosing the correct lighting source it is
possible to highlight different types of defect more easily. With the advances that have been
made in lighting technology in recent years, this has enabled lighting to be used to enhance the
images available and in turn this enables defects to be highlighted more easily with a resultant
reduction in processing required and an increase in speed and accuracy.
Most AOI systems have a defined lighting set. This will depend upon the operation required
and the product types to be tested. These have usually been optimised for the anticipated
conditions. However sometimes some customization may be required, and an understanding of
lighting is always of use.
A variety of types of lighting are available:
 Fluorescent lighting: Fluorescent lighting is widely used for AOI, automated optical
inspection applications as it provides an effective form of lighting for viewing defects on
PCBs. The main problem with fluorescent lighting for AOI applications is that the lamps
degrade with time. This means that the automated optical inspection system will be subject
to a constantly changing levels and quality of light
 LED lighting: The development of LED lighting has meant that AOI, automated optical
inspection systems are able to adopt a far more stable form of lighting. Although LED
lighting does suffer from a reduction in light output from the LEDs over time, this can be
compensated for by increasing the current. Using LED lighting, the level of lighting can
also be controlled. LEDs are therefore a far more satisfactory form of lighting than
fluorescent or incandescent lights that were used years ago
 Infra-red or ultra-violet: On some occasions infra-red or ultra-violet lighting may be
required to enhance certain defects, or to enable automated optical inspection to be carried
out to reveal certain types of defect.
Apart from the form of lighting, the positioning of the lighting for an automatic optical
inspection system, AOI, is equally important. The light sources require positioning to not only
to ensure that all areas are well light, which is particularly important when certain components
may cast shadows, but also to highlight defects. Careful adjustment may be needed for
different assemblies.

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AOI Imaging System
There are two classes of imaging systems: vertical camera only systems, (called 2D or two-
dimensional), and 3D or three-dimensional systems. The 3D systems incorporate angled
cameras. 2D systems are of course cheaper to build, and simpler to use, but they have some
inherent limitations in fault coverage. Certain defects such as lifted gull-wing leads are very
difficult to see with a single, straight down satellite view of the board. Angled cameras are
much more advantageous for detecting this very important fault category. Some 2D systems
attempt to overcome their lack of angled cameras by using color. One approach is to use a
vertical camera with colored lights at various angles; these lights produce a color banding
profile on the top of a gull-wing lead. From that banding profile one can indirectly infer that
perhaps the lead is lifted and not making contact. Angled cameras provide a more direct,
positive sensing capability in that by nature, they can “see”the position of the lifted lead
directly, and without inference. Four angled cameras are typically employed in a 3D system –
one each to cover north, south, east, and west – in addition to a single vertical camera. When
using angled cameras at high magnification, board warpage becomes a very significant issue. A
small amount of warp can move the target image completely out of the inspection window.
Therefore, a modern AOI system must have a competent warp correction system. Some
systems make only a single height correction for the entire board, but warp correction should
be more comprehensive, compensating at every field of view (FOV). Comprehensive warp
correction ensures accurate placement of the inspection window and eliminates yet another
source of false calls.
How the defects are found
Reference image
For all kind of AOI and AVI machines, there must be a reference image in order to find out the
defects on the boards. It is used to compare with the scanned image to identify the defects. This
reference image can be either a CAD data or a golden board image. A CAD data is a
Computer-aided design data of PCBs which includes much information such as the circuit
layout, solder mask layout, etc. These CAD data are created by CAD software. All regions are
classified for a CAD data. Another kind of reference image is the golden board image. A
golden board image is an image of a good board. To ensure the board is a good board, it is
normally checked manually by some magnifying devices first. After that, it will be scanned by
AOI/AVI machines and the image captured will be the golden board image. Sometimes, the
golden board image is created by scanning a number of boards and using the average image of
these boards as the golden board image.
Automatic Optical Inspection Platforms
AOI systems are available in 3 platforms, Pass Through, Magazine or Cartridge Fed and
Bench Top and are available in 2 imaging options, scanners or camera based systems.
Pass Through Systems
They are normally used in volume manufacture where the inspection system is part of the
manufacturing line. The first optical inspection systems were designed for inline use. Early

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machines needed constant attention but systems now based on desk top units offer a better
solution.
Magazine Fed Systems
Mounted on to a magazine feeder the system will inspect a magazine of up to 50 boards
without operator intervention. It is important to consider how the boards are identified so the
faulty boards can be cross referenced to their fault data. A common approach to this is to use
bar codes fitted to the board in a repeatable position so that they can be read by the inspection
system.
Bench Top Systems
As the name implies the inspection system is mounted on a bench in a convenient location to
production. Boards or panels are loaded and unloaded individually with faults being either
checked locally at the machine or fault data being down loaded to a rework station. This type
of system gives the most versatile approach to inspection.
Scanner Systems
Line scan cameras are used to image boards for inspection using similar techniques to
conventional office scanners. Generally scanner based systems have limitations on component
size and the quality of solder inspection. For the remainder of this script scanner systems will
be ignored, as they should be considered as a short-term solution to a continuing requirement
Camera Based Systems
Inspection systems employing cameras offer the best approach to the inspection process. They
allow flexibility in the lighting techniques employed and achievable resolution. The various
aspects associated with camera choice.
Comparing 2D and 3D automatic optical inspection
Inspection technologies compared
Product defects during the automated assembly and soldering of electronic assemblies are
unavoidable. More and more, systems for AOI and automated X-ray inspection (AXI) are
being deployed to assure these defects are detected and to further optimize the process.
Various technologies are used for this:
 Cameras with orthogonal (vertical) top views (AOI, 2D technology).
 Cameras with an additional angled view (AOI, 2D technology).
 Height measurement of the board with components (AOI, 3D technology).
 X-ray inspection (AXI, 2D, 2.5D or 3D technology).
Genuine 3D processes, featuring actual height measurement and volumetric measuring, used to
be too inaccurate, expensive and slow. But further technical development of the sensors and
evaluation hardware has allowed various genuine 3D technologies to make inroads into AOI.
Depending on the technology, this permits height measurement for components, IC pins and
solder joints.

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Types of defects and the ability to identify them
The increased component density on electronic assemblies and other influences lead to smaller
and smaller connection pads. These trends increase the defect spectrum: chip lifted leads in all
angles, ICs/BGAs that are not coplanar (if no X-ray inspection is conducted), poor wetting on
QFNs and dual flat no-leads (DFN), non-coplanar plugs, bent plug pins, relational
measurement, measurement tasks (LEDs), colour analysis, head in pillow on BGAs (only with
X-ray inspection) as well as additional solder and wetting errors on individual, concealed
solder joints. Most of these types of defects can be found reliably and with high throughput
using modern, high-quality 2D AOI. For some (extended) types of defects, this is only partially
true.
Strengths and limitations of 2D technology
One of the first advantages to note when comparing 2D and 3D inspection approaches is the
ease of programming 2D systems versus 3D systems. Since 2D inspection approaches have
been around for many years, much time has been spent on the development of software
interfaces and image processing to simplify the programming process. In addition, inspection
cycle times are significantly faster since fewer 2D images are captured and processed. The
camera, optics, and lighting used in a 2D system allows for inspection flexibility, where
assemblies with small and tall components (SMT and through-hole assemblies) can be
inspected at the same time. Inspection for printed nomenclature, polarity marks and even
colour, can be trained and inspected easily in 2D. Multiple side-angle 2D cameras can also be
used to inspect solder quality on J-Lead devices, and even part or polarity markings printed on
the sides of through-hole components. Finally, the cost of a 2D system is lower in comparison
to a similar 3D system. Since true volumetric height information cannot be measured, 2D
inspection systems are limited compared to 3D systems. The coplanarity of height-sensitive
devices, such as BGA packages and leaded components, can be inspected in 2D using multi-
angled coloured lighting and side-angle cameras. However, these methods will be susceptible
to an increase in false calls, a need for additional programming and cycle time, and possible
escapes. However, 2D technology also has its limits. For example, it cannot perform inspection
of hidden solder joints or measurement of connectors (straight alignment for later automatic
joining). Furthermore, optimization of defect rates for certain defect features is possible only
with comparatively expensive means, while direct evaluation of 3D data is not possible and
higher pseudo defect rates occur for some defect features.
Strengths and limitations of 3D technology
The newer 3D technology has been used for some time in surface mount technology (SMT)
production for inspection of paste print after the screen printer. Now, it is also being
successfully used for post-reflow inspection. For the first time, actual height information can be
obtained and additional defect features detected.
The primary advantage of 3D inspection over 2D inspection is that it provides true volumetric
height information. Coplanarity on lifted leads and other height-sensitive devices can be
detected without difficulty. Since height data can be measured, AOI programmers can specify

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the precise height tolerance acceptable for a particular component. Using 3D inspection for
coplanarity detection also provides a significant reduction in false calls versus the use of 2D
inspection. However, there are also disadvantages of using 3D inspection systems. 3D
inspection approaches cannot check for printed part nomenclature, polarity marks, or color.
Even with the use of multiple digital projectors, shadowing issues may still occur depending on
circuit-board layout and the varying heights of adjacent components. Components not on the
same level and bent leads are detected. Also for the first time, additional features involving
height can be inspected. Basic features, such as the presence of components, can finally be
checked more easily and pseudo defects reduced.
Despite this, 3D technology also has some drawbacks and limitations: More work is involved
in the process of defect detection, which drives up associated costs. Technological limitations
include the fact that many basic defect features, such as a number of polarity marks and
characters, cannot be identified.
Combining 2D and 3D AOI: The Most Effective Inspection
In order to attain the highest level of quality assurance (QA), high-precision AOI capability is
essential. Combining AOI methods, using both two-dimensional (2D) and three-dimensional
(3D) inspection strategies, are proving to be the most effective solution for thorough inspection
coverage in today’s advancing manufacturing environments.
The common methodology used in most 3D AOI systems is Moiré 3D phase-shift image
processing. In this application, multiple projectors are used to digitally project multiphase
digital fringe patterns (vertical lines) on a specified FOV. A 2D camera is then used to capture
the pattern of lines and any line distortions due to component(s) with heights greater than the
PCB surface. Through phase-shift analysis, a 3D height map can be created, and the height can
be measured on any point of this FOV. Finally, a color2D image of this FOV can be applied to
the height map to provide a realistic 3D rendered image. Digital projectors represent a mature
technology that has been in use since the early 1990s, and is now being used in a variety of
applications. The numerous technological advancements of digital projectors have allowed
manufacturers to optimize the dynamic range projection capability. For example, through the
control of appropriate soft-ware, the projectors can be digitally programmed to project fringe
patterns at multiple frequencies for greater inspection flexibility. As 3D inspection becomes
more widespread, the question arises whether 100 percent 3D inspection will be the most
effective strategy for inspection, without the aid of 2D inspection. Many believe that this is not
the case, and that 2D inspection still serves as a viable tool for comprehensive inspection
coverage on PCB assemblies. However, 2D inspection approaches have limitations, and that is
where 3D inspection can shine.

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CONCLUSIONS & FURTHER SCOPE
All in all my internship at Maruti Suzuki was very beneficial. Not only did I learn about the
working of a professional company and gained great insights into the manufacturing process
but I also learned how to maintain composure in a professional working environment and work
independently.
Also, I learned that in a company one is not only responsible for his work profile but his work
also influences all other members i n the team. A great performance can really lift up the team.
Also, one’s work also serves as input data for other employees so it has to be very accurate.
Working in a company is about working in tandem to produce desired results. So I realized the
indispensable value of teamwork.
Coming to the further scope in the company it is a great opportunity to be part of the company
and has an insight to how India’s largest automobile manufacturer works. But the work here is
more about learning about the existing systems and solving line issues. There is not a lot of
innovation and projects which are undertaken by the employees in all departments. Only the
engineering department does that stuff which actually is not a very good thing. Most of these
projects are done by Suzuki in Japan.
At last, I would like to conclude with the fact that I really learned how the industry runs and
what skill set is needed to be part of it which I am sure will definitely help me in doing things in
the right way i n future. Also, I would like to convey my sincere thanks to my project guides
and my faculty coordinator for such an enriching experience.

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