Development of vision inspection system for automotive assembled part.

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DEVELOPMENT OF VISION INSPECTION SYSTEM

FOR AUTOMOTIVE ASSEMBLED PART

RADIN PUTERI HAZIMAH BINTI RADIN MONAWIR

B050910192

UNIVERSITII TEKNIKAL MALAYSIA MELAKA 2013


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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

DEVELOPMENT OF VISION INSPECTION SYSTEM FOR

AUTOMOTIVE ASSEMBLED PART

This report submitted in accordance with requirement of Universiti Teknikal Malaysia Melaka (UTeM) for the Bachelor Degree of Manufacturing Engineering

(Robotics and Automation) (Hons.)

by

RADIN PUTERI HAZIMAH BINTI RADIN MONAWIR B050910192

900507-08-6506

FACULTY OF MANUFACTURING ENGINEERING 2013


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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS LAPORAN PROJEK SARJANA MUDA

TAJUK: DEVELOPMENT OF VISION INSPECTION SYSTEM FOR AUTOMOTIVE

ASSEMBLED PART

SESI PENGAJIAN: 2012/13 Semester 2

Saya RADIN PUTERI HAZIMAH BINTI RADIN MONAWIR

mengaku membenarkan Laporan PSM ini disimpan di Perpustakaan Universiti Teknikal Malaysia Melaka (UTeM) dengan syarat-syarat kegunaan seperti berikut:

1. Laporan PSM adalah hak milik Universiti Teknikal Malaysia Melaka dan penulis. 2. Perpustakaan Universiti Teknikal Malaysia Melaka dibenarkan membuat salinan untuk

SULIT

TERHAD

TIDAK TERHAD

(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia sebagaimana yang termaktub dalam AKTA RAHSIA RASMI 1972)

(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan)

Alamat Tetap:

Kg. Sg. Nipah Darat, 36200 Selekoh, Perak.

Tarikh:

__18/06/2013_____________________

Disahkan oleh:

Cop Rasmi:

Tarikh: 20/5/2013

** Jika Laporan PSM ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasa/organisasi berkenaan dengan menyatakan sekali sebab dan tempoh laporan PSM ini perlu dikelaskan sebagai SULIT atau TERHAD.


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DECLARATION

I hereby, declared this report” Development Vision Inspection System for Automotive Assembled Part” is the results of my own research except as cited in references.

Signature : ………..

Author’s Name : RADIN PUTERI HAZIMAH BINTI

RADIN MONAWIR

Date : 03/06/2013


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APPROVAL

This report is submitted to the Faculty of Manufacturing Engineering of UTeM as a partial fulfillment of the requirements for the degree of Bachelor of Manufacturing Engineering (Robotics and Automation) (Hons.). The member of the supervisory committee is as follow:

..………..


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DEDICATION

This work is dedicated to my beloved late father, who always inspired me to be competent and work hard in every works that I have done. Special dedicated to my mother whose love and pray accompanies throughout my life. It is also dedicated to my fiancé, who always supporting and motivating me along the accomplishment of this project.


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ACKNOWLEDGEMENT

I would like to thank my supervisor, En. Mohd Nazrin bin Muhamad and Dr. Fairul Azni bin Jafar for their helpful advice. Their patience in guiding me is very precious. I am grateful to En. Mohd Nazmin bin Maslan for his advices especially for formatting report techniques. Last but not least, I feel grateful to Universiti Teknikal Malaysia Melaka (UTeM) for providing me opportunity doing this research.


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ABSTRAK

Pembangunan Sistem Pemeriksaan Visual merupakan projek kerjasama antara UTeM dan PHN Industri Sdn.Bhd. Projek ini dijalankan khusus untuk menghasilkan algoritma menggunakan untuk system visual menggunakan perisian MATLAB dan kemudiannya algoritma ini diuji prestasinya melalui beberapa ujian. Dua algoritma telah dibangunkan bagi sistem visual ini iaitu; Perhubungan Korelasi (Coefficient Correlation, CC) dan Penjumlahan Kaedah Kuasa Dua menggunakan Perhubungan Silang (Summing Square Difference using Cross Relation,SSDXCORR). Kedua-dua algoritma ini diuji dengan menggunakan sampel-sampel yang mempunyai pelbagai kecerahan, putaran dan kecerahan. Kedua-dua algoritma ini juga diuji masa pemproessan imejnya dan ketepatan semasa diuji dengan sampel yang diubah secara rawak. Hasil ujian menunjukkan CC mempunyai prestasi yang lebih baik dari SSDXCORR bagi ujian kecerahan yang berlainan dan ketepatan. Manakala, SSDXCORR mempunyai prestasi yang lebih baik dalam ujian orientasi dan kelajuan masa pemprosesan imej.


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ABSTRACT

The Development of Vision Inspection System for Automotive Assembled Part is a project between UTeM and PHN Industry Sdn. Bhd. The main purposes of this project are to develop algorithms for vision inspection system using MATLAB and to verify the performance of vision inspection system that has been developed. Two algorithms; Coefficient Correlation (CC) and Summing Square Method using Cross Relation (SSDXCORR) have been developed and tested. Both algorithms performance have been tested by subjecting samples with different rotations and brightness. Both algorithms performance has also being verified by observing image processing time and accuracy while subjecting randomly modified images samples. Through the experimental result of this study, it is concludes that CC has better performance than SSDXCORR in term of higher accuracy and higher percentage of detection under different brightness and SSDXCORR has better performance in term of faster image processing time and higher percentage detection while subjecting variant image orientation. In a nutshell, this study has achieved its objectives.


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TABLE OF CONTENTS

Declaration i

Approval ii

Dedication iii

Acknowledgement iv

Abstrak v

Abstract vi

List of tables x

List of figures xi

List of abbreviations, symbols and nomenclature xii

CHAPTER 1:INTRODUCTION

1.1 Project Background 1

1.1.1 Vision Inspection System 1

1.1.2 Advantages using vision inspection system 2

1.1.3 Applications of Vision Inspection System 4

1.1.4 UIC Collaboration 6

1.1.5 Company Profile 8

1.2 Problem statement 8

1.3 Objectives 10

1.4 Scope 10

CHAPTER 2:LITERATURE REVIEWS

2.1 Image capturing hardware and software 11

2.3 Image Processing Methods 14

2.3.1 Template Matching 15

2.3.2 Edge Detection 19

2.3.3 Multiple Recognition 20

2.3.4 Comparison of Methods 25

2.4 Software 26


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viii

2.4.2C++ Language 27

2.4.3 LabVIEW 27

CHAPTER 3 :METHODOLOGY

3.1 Project Concept 29

3.2 Hardware and Software for Image Capturing 31

3.2.1 Software and Hardware Specifications 32

3.2.2 Hardware and Software setup 34

3.3 Image Processing Techniques 36

3.4 Part and Defect Information 38

3.5 Algorithms Development 40

3.5.1 Correlation Matching Algorithms 40

3.5.2 SSDXCORR 44

3.6 Environmental, Experimental and Sample Set Up 47

3.6.1 Experiment A: Parameter Identification 48

3.6.2 Experiment B: Variant: Input Orientation 51

3.6.3 Experiment C: Brightness Adjustment 53

3.6.4 Experiment D: Accuracy 53

3.6.5 Coefficient Correlation versus SSDXCORR 55

CHAPTER 4: RESULTS AND DISCUSSION

4.1Experiment A: Parameter Identification 56

4.1.1 Template Distance Selection 56

4.1.2 Threshold Adjustment 60

4.2 Experiment B: Variant Input Orientation 64

4.3Experiment C:Brightness Adjustment 66

4.4Experiment D: Accuracy 69

4.5Summarization of chapter 73

CHAPTER5 :CONCLUSION 74 REFERENCES 76 APPENDICES


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ix A Samsung Galaxy Ace S5831 Specifications B Bluetooth specifications

C Bluetooth vs WiFi D Yue Wu's Coding

E Part1 Algorithms for Correlation Matching F Part2 Algorithms for Correlation Matching G Algorithms for SSDXCO


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x

LIST OF TABLES

1.1 Comparison vision system and human. 3

2.1 Summarization of image capturing hardware. 13

2.2 Image processing methods 14

2.3 Comparing method of inspection. 25

3.1 Specification of android application 32

3.2 Sample images of side 1 and 2 without cropped. 49 3.3 Side 1 and side 2 sample images that have been cropped. 50 3.4 Rotation of side 1 and side 2 at 10o -40o. . 52 3.5 Rotation of side 1 and side 2 at 45 o ,90-o , 135o and 180o. 52

3.6 Randomly modified image sample. 54

4.1 Range of template matching when template from input at different 59

4.2 Results for Sid 1 and side 2 . 61

4.3 Time elapsed for CC 62

4.4 Time elapsed for SSDXCORR 63

4.5 Results for images rotated at 10o -40o. 64

4.6 Results for rotation multiple of 45o 65

4.7 Summarized results of rotated images (CC) 65

4.8 Summarized results of rotated images (SSDXCORR) 66 4.9 Results when decreasing brightness of sample images. 66 4.10 Results when increasing brightness of sample images. 68 4.11 Summarized results of Table 4.7 and Table 4.8 (CC). 68 4.12 Brightness adjustment result by using SSDXCORR 69

4.13 Accuracy test 1 70

4.14 Result of repeating test 1 in Table 4.10 71

4.15 SSDXCORR results on random sampling 72

4.16 Summarized results of accuracy testing 72


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LIST OF FIGURES

1.1 Comparison vision system and human. 3

2.1 Summarization of image capturing hardware. 13

.2.2 Image processing methods 14

2.3 Comparing method of inspection. 25

3.1 Specification of android application 32

3.2 Sample images of side 1 and 2 without cropped. 49 3.3 Side 1 and side 2 sample images that have been cropped. 50 3.4 Rotation of side 1 and side 2 at 10o -40o. . 52 3.5 Rotation of side 1 and side 2 at 45 o ,90-o , 135o and 180o. 52

3.6 Randomly modified image sample. 54

4.1 Range of template matching when template from input at different 59

4.2 Results for Sid 1 and side 2 . 61

4.3 Time elapsed for CC 62

4.4 Time elapsed for SSDXCORR 63

4.5 Results for images rotated at 10o -40o. 64

4.6 Results for rotation multiple of 45o 65

4.7 Summarized results of rotated images (CC) 65

4.8 Summarized results of rotated images (SSDXCORR) 66 4.9 Results when decreasing brightness of sample images. 66 4.10 Results when increasing brightness of sample images. 68 4.11 Summarized results of Table 4.7 and Table 4.8 (CC). 68 4.12 Brightness adjustment result by using SSDXCORR 69

4.13 Accuracy test 1 70

4.14 Result of repeating test 1 in Table 4.10 71

4.15 SSDXCORR results on random sampling 72

4.16 Summarized results of accuracy testing 72


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LIST OF ABBREVIATIONS, SYMBOLS AND

NOMENCLATURE

CC - Coefficient Correlation CR - Cross Relation

CCD - Charged-couple device CDI - Cloudy Day Illuminator

CMOS - Complementary Metal Oxide Semiconductor DOAL - Diffuse On Axis Light

EDR - Enhance Data Rate

FKP - Fakulti Kejuruteraan Pembuatan

SCDI - Square Continuous Diffuse Illumation SSD - Sum Squared Different

MATLAB - MATrix LABoratory PAN - Personal Area Network PC - Personal Computer PHN - Proton-Honda-Nagoya ROI - Region of Interest

SSDXCORR - Cross Correlation based Sum of Squared Difference UTeM_ - Universiti Teknikal Malaysia Melaka

Wi-Fi - Wireless fidelity W/O - Without


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CHAPTER 1

INTRODUCTION

The development of Vision Inspection System for Automotive Assembled Part is a university-industry collaboration (UIC) project between PHN Industry Sdn. Bhd and UTeM. In this project, a vision inspection system for assembled automotive part has been developed. This project focused on image processing, developing algorithm and programming for vision system using MATLAB. Sample for this research is a car door. This system inspected the assembled metal part by firstly capturing the image, processing the image and comparing the image with template images data before executing result; whether current part is accepted or rejected.

1.1Project Background

1.1.1 Vision Inspection System

Vision system is generally known as automatic extraction of information from images. This system consists of lens, lighting, sensors, and vision processing and communication unit. They commonly used in various fields, medical, traffic controlling and industry, normally for checking and inspection purpose. Counting, measurement, location and decoding are examples of familiar application of this system. Figure 1.1 showed an example of vision system layout.


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Figure 1.1: Archetypal machine vision system. (Gr aves & Batch elor , 2003) .

1.1.2 Advantages using vision inspection system

Automated inspection stage by using vision system has many advantages; reduce pass through defects, increase yield and can track and trace where defects occurred. In real industry world, precision and quality of the products are very important. Everything must lies within tolerances and comply their requirements. Issues regarding pass through defected products to the market, which finally need to be recall back is definitely brings bad reputation to company itself. Besides, company has to burden cost incurred; cost to call back products and other penalty cost. Therefore, vision systems as inspection system can lead to fewer catastrophes go to customer hand; therefore reduce the cost incurred and maintain good reputation of company. Example of mislabelled food product is shown in Figure 1.2 below:


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Figure 1.2 : Exampled of mislabelled product (Microscan System Inc., 2012).

On top of that, vision inspection system also enabled company to have better yield; ability to turn input product to saleable end product. The soon the defects are eliminated , especially from entering next stage, the more the material can be saved from being scrap or need to rework. Moreover, vision inspection system may also keep the defected and good products record after being inspected. Company may have as many records as they want relevant to their storage memory. Therefore, if any defected products miss into next stage or line, it still can be track and trace based on storage memory.

Machine vision also has many advantages as compared to human inspectors. This can be explained through comparison in Table 1.1 below:

Table 1.1: Comparison vision system and human.

Aspects Vision system Human

Work duration Vision system work tirelessly even for a long time.

Human will get tired and need rest after certain time work.

Quality of work Can work consistently and repetitively. They can work all day for the same work with minimum error. They follow all parameters setting as before.

Human inspector is inconsistent and easily tired with repetitive work. They may lost concentration and error may increase as time being.


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4 1.1.3 Applications of Vision Inspection System

According to (Graves & Batchelor, 2003)and Steger, Ulrich and Wiederman (2008) vision system provided imaging-based automatic inspection and analysis for applications such as automatic inspection, process control, and robot guidance in industry. Vision system is increasingly used with robot automation to perform various task; part identification, inspection, location, orientation, and range finding (A.Rehg, 2000).

Part identification is an example of vision system application that has been commercialized now. The image that has been captured is stored in memory and later will be used as data to distinguish part as they enter the work cell. From this storage data, system learns the characteristic of different parts and identifies each part from its two-dimensional silhouette. This feature can stand-alone, act as sorting purpose or air with inspection ability, where system recognise object and count the number of object. For example, in beverages packaging, the system will recognise the bottle and inspect whether the number of bottles inside a box is correct (refer to Figure 1.3).

Figure 1.3: Counting application of vision system, (Microscan System Inc., 2012).

Part inspection also can be done by using vision system. Inspection term here is used for dimensional checking; diameter of the part (Figure 1.4) and geometrical integrity; number of holes (Figure 1.5). Parts are measured by camera and the dimensions are calculated.


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Figure 1.4: Vision system inspect spanar dimension. (Micr oscan System In c., 2012) .

Figure 1.5: Number of holes is counted by using vision system (Micr oscan System In c., 2012) .

Vision system also allow user to locate randomly placed parts on X-Y grid in. It measures X and Y distances from the centre part of camera coordinate system to the centre of the randomly placed part(Figure 1.6). This method also can be used to know part orientation by applying certain extra mathematical formulas.

Figure 1.6: Locating the position and knowing orientation of part is some of the application in vision system (Microscan System Inc., 2012).


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In the meanwhile, range finding is used to measure and calculate cross-sectional of parts. Other than above application, vision system also able to decode. This can be done by capturing and processing the bar code (Figure 1.7).

Figure 1.7: Decoding application by using vision system (Microscan System Inc, 2012).

Note that, beside integrated with robot, machine vision also can be integrated with PLC or stand-alone too (A.Rehg, 2000).

1.1.4 UIC Collaboration

Development Vision Inspection System for Automotive Assembled Part is university-industry collaboration (UIC) project between PHN Industry Sdn. Bhd. University-Industry Collaboration (UIC) is a strategic cooperation which provided win-win results between university and industry.

In UIC, industrial provides data and field of research and university share the latest knowledge. Moreover UIC is a golden opportunity for scholar to research and proposed solution for industrial problems. For industry, it is a great opportunity to explore new high-tech solution with low investment and risk.


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Figure 1.8: UIC Concept.

The collaboration between UTeM and PHN opens numerous opportunities. The development of the system benefits the UTeM in term of knowledge gain, industry exposure, professional acknowledgement (i.e. IR/PE) and portfolio proliferation. Meanwhile, PHN gains advantages in good return of investment (ROI) by producing higher number of quality products yet less investment cost.

*


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8 1.1.5 Company Profile

PHN Industry Sdn. Bhd., abbreviated from Proton-Hicom-Nagoya is a Malaysian automotive manufacturer components founded in 1990. PHN is headquartered in Shah Alam, Selangor, Malaysia. It also owns four other plants in BB, USJ, Pekan and Melaka. It is a part of DRB Hicom group.

There are three main activities; stamping, assembly and die manufacturing. Stamping is normally done by using dies that are provided by customer to shape the sheet metal. For assembly, normally, the part that has been welded has been stamped in the PHN itself or from outsourcing. Meanwhile, in die manufacturing, PHN manufacture dies to be used internally and imported to external market.

Figure 1.10: Main PHN Industry Customers.

1.2 Problem statement

PHN Industry Sdn. Bhd is well-known as one of established suppliers for car manufacturers in Malaysia; Proton, Perodua, Toyota and Honda. With mission To provide our customers with superior quality product at a competitive price”, PHN Industry always give the best to ensure their supplied components always comply customers’ requirement. However, in real world, there are many obstacles they have to handle.


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Figure 1.2 : Exampled of mislabelled product (Microscan System Inc., 2012).

On top of that, vision inspection system also enabled company to have better yield; ability to turn input product to saleable end product. The soon the defects are eliminated , especially from entering next stage, the more the material can be saved from being scrap or need to rework. Moreover, vision inspection system may also keep the defected and good products record after being inspected. Company may have as many records as they want relevant to their storage memory. Therefore, if any defected products miss into next stage or line, it still can be track and trace based on storage memory.

Machine vision also has many advantages as compared to human inspectors. This can be explained through comparison in Table 1.1 below:

Table 1.1: Comparison vision system and human.

Aspects Vision system Human

Work duration Vision system work tirelessly even for a long time.

Human will get tired and need rest after certain time work.

Quality of work Can work consistently and repetitively. They can work all day for the same work with minimum error. They follow all parameters setting as before.

Human inspector is inconsistent and easily tired with repetitive work. They may lost concentration and error may increase as time being.


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4 1.1.3 Applications of Vision Inspection System

According to (Graves & Batchelor, 2003)and Steger, Ulrich and Wiederman (2008) vision system provided imaging-based automatic inspection and analysis for applications such as automatic inspection, process control, and robot guidance in industry. Vision system is increasingly used with robot automation to perform various task; part identification, inspection, location, orientation, and range finding (A.Rehg, 2000).

Part identification is an example of vision system application that has been commercialized now. The image that has been captured is stored in memory and later will be used as data to distinguish part as they enter the work cell. From this storage data, system learns the characteristic of different parts and identifies each part from its two-dimensional silhouette. This feature can stand-alone, act as sorting purpose or air with inspection ability, where system recognise object and count the number of object. For example, in beverages packaging, the system will recognise the bottle and inspect whether the number of bottles inside a box is correct (refer to Figure 1.3).

Figure 1.3: Counting application of vision system, (Microscan System Inc., 2012).

Part inspection also can be done by using vision system. Inspection term here is used for dimensional checking; diameter of the part (Figure 1.4) and geometrical integrity; number of holes (Figure 1.5). Parts are measured by camera and the dimensions are calculated.


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Figure 1.4: Vision system inspect spanar dimension. (Micr oscan System In c., 2012) .

Figure 1.5: Number of holes is counted by using vision system (Micr oscan System In c., 2012) .

Vision system also allow user to locate randomly placed parts on X-Y grid in. It measures X and Y distances from the centre part of camera coordinate system to the centre of the randomly placed part(Figure 1.6). This method also can be used to know part orientation by applying certain extra mathematical formulas.

Figure 1.6: Locating the position and knowing orientation of part is some of the application in vision system (Microscan System Inc., 2012).


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In the meanwhile, range finding is used to measure and calculate cross-sectional of parts. Other than above application, vision system also able to decode. This can be done by capturing and processing the bar code (Figure 1.7).

Figure 1.7: Decoding application by using vision system (Microscan System Inc, 2012).

Note that, beside integrated with robot, machine vision also can be integrated with PLC or stand-alone too (A.Rehg, 2000).

1.1.4 UIC Collaboration

Development Vision Inspection System for Automotive Assembled Part is university-industry collaboration (UIC) project between PHN Industry Sdn. Bhd. University-Industry Collaboration (UIC) is a strategic cooperation which provided win-win results between university and industry.

In UIC, industrial provides data and field of research and university share the latest knowledge. Moreover UIC is a golden opportunity for scholar to research and proposed solution for industrial problems. For industry, it is a great opportunity to explore new high-tech solution with low investment and risk.


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Figure 1.8: UIC Concept.

The collaboration between UTeM and PHN opens numerous opportunities. The development of the system benefits the UTeM in term of knowledge gain, industry exposure, professional acknowledgement (i.e. IR/PE) and portfolio proliferation. Meanwhile, PHN gains advantages in good return of investment (ROI) by producing higher number of quality products yet less investment cost.

*


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8 1.1.5 Company Profile

PHN Industry Sdn. Bhd., abbreviated from Proton-Hicom-Nagoya is a Malaysian automotive manufacturer components founded in 1990. PHN is headquartered in Shah Alam, Selangor, Malaysia. It also owns four other plants in BB, USJ, Pekan and Melaka. It is a part of DRB Hicom group.

There are three main activities; stamping, assembly and die manufacturing. Stamping is normally done by using dies that are provided by customer to shape the sheet metal. For assembly, normally, the part that has been welded has been stamped in the PHN itself or from outsourcing. Meanwhile, in die manufacturing, PHN manufacture dies to be used internally and imported to external market.

Figure 1.10: Main PHN Industry Customers.

1.2 Problem statement

PHN Industry Sdn. Bhd is well-known as one of established suppliers for car manufacturers in Malaysia; Proton, Perodua, Toyota and Honda. With mission To provide our customers with superior quality product at a competitive price”, PHN Industry always give the best to ensure their supplied components always comply customers’ requirement. However, in real world, there are many obstacles they have to handle.