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UNIVERSITI TEKNIKAL MALAYSIA MELAKA STRUCTURAL DESIGN AND ANALYSIS OF AUTONOMOUS GUIDED VEHICLE (AGV) FOR PARTS SUPPLY This report submitted in accordance with requirement of the Universiti Teknikal Malaysia Melaka (UTeM) for the Bachelor’s Degree in Mechanical Engineering Technology (Automotive Technology) (Hons.) by KHAIRUL HAZWAN BIN MOHD RASIT B071110332 921106-04-5343 FACULTY OF ENGINEERING TECHNOLOGY 2015

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Page 1: UNIVERSITI TEKNIKAL MALAYSIA MELAKA ...eprints.utem.edu.my/15448/1/STRUCTURAL DESIGN AND...UNIVERSITI TEKNIKAL MALAYSIA MELAKA STRUCTURAL DESIGN AND ANALYSIS OF AUTONOMOUS GUIDED VEHICLE

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

STRUCTURAL DESIGN AND ANALYSIS OF AUTONOMOUS

GUIDED VEHICLE (AGV) FOR PARTS SUPPLY

This report submitted in accordance with requirement of the Universiti Teknikal

Malaysia Melaka (UTeM) for the Bachelor’s Degree in Mechanical Engineering

Technology (Automotive Technology) (Hons.)

by

KHAIRUL HAZWAN BIN MOHD RASIT

B071110332

921106-04-5343

FACULTY OF ENGINEERING TECHNOLOGY

2015

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DECLARATION

I hereby, declare that this report entitled “Structural Design And Analysis of

Autonomous Guided Vehicle (AGV) For Parts Supply” is the result of my own research

except as cited in the references.

Signature : .........................................................

Author’s Name : .........................................................

Date : .........................................................

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APPROVAL

This report is submitted to the Faculty of Engineering Technology of UTeM as a partial

fulfillment of the requirements for the Bachelor’s Degree in Mechanical Engineering

Technology (Automotive Technology) (Hons.). The member of the supervisory is as

follow:

…………………………….

(Project Supervisor)

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ABSTRACT

For the last 10 years, the world economic growth rapidly and have been becomes the battle

stage between the industrial companies. Autonomous Guided Vehicle is introduced to support

the supply system however the initial investment is very high and it cannot convince a certain

company to invest such amount of money for the system. In this project, the focus research is

more on a low cost lightweight AGV development. Lightweight design leads to less energy

consume to carry its body. The purpose of this study is design a low cost, light body AGV that

to be used in parts supply using polyboxes. On top of that, the structural strength analyses are

performed through computer aided engineering (CAE) simulation. The structure of the AGV

also put into consideration of the vehicle architecture, material properties and product

maintainability in innovative approach.

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ABSTRAK

Sejak 10 tahun kebelakangan ini, pertumbuhan ekonomi dunia semakin cepat dan telah

menjadi pentas pertempuran di antara syarikat-syarikat industri. Kenderaan autonomi

berpandu diperkenalkan untuk menyokong sistem bekalan bagaimanapun pelaburan awal

adalah sangat tinggi dan sukar untuk meyakinkan syarikat tertentu untuk melabur jumlah wang

untuk sistem itu. Dalam projek ini, penyelidikan tumpuan adalah lebih kepada kos rendah

serta rangka AGV yang ringan. Reka bentuk yang ringan membawa kepada tenaga yang

kurang untuk menjalankan badannya . Tujuan kajian ini adalah untuk reka bentuk AGV yang

akan digunakan di bahagian-bahagian bekalan alatan yang menggunakan polyboxes. Selain itu,

reka bentuk kekuatan struktur akan diuji dan dianalisis melalui bantuan komputer simulasi

kejuruteraan. Struktur AGV juga sudah dimasukkan ke dalam pertimbangan seni bina

kenderaan, sifat bahan dan penyelenggaraan produk dalam pendekatan inovatif .

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DEDICATION

Dedicated to my father, Mohd Rasit bin Mohd Hassan and my mother, Norkiah binti Hashim.

To my supervisor, Ir. Mazlan bin Ahmad Mansor, co-supervisor, Mr. Mohd Suffian bin Ab

Razak, lecturers and friends for all of their help and friendship.

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ACKNOWLEDGEMENT

First of all, I express my deepest thanks and gratitude’s to Allah S.W.T who give me

the spirit and the soul throughout the duration of my final year project. I have completed this

project even though there are many difficulty and hardship along the way.

I would like to express my appreciation and deep respects to my supervisor, Ir. Mazlan

bin Ahmad Mansor for the guidance and encouraged during finishing this project. Not to

forget, my co-supervisor Mr. Mohd Suffian bin Ab Razak for his constant guidance and

support during my thesis writing is invaluable to me and continuous direction and opinion

regarding the flow of the project has invaluable contribution to achieve the objectives of the

project.

Thanks to my family, who has been the loveliest advisor to give constant support and

inspiration through my campus life. Their supports are meant so much to me in finishing this

project. Last but not least, I thank everyone who involved directly and indirectly in this project.

Without them, this PSM report will not good completed like this.

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TABLE OF CONTENT

ABSTRACT i

ABSTRAK ii

DEDICATION iii

ACKNOWLEDGEMENT iv

TABLE OF CONTENTS v

LIST OF TABLES ix

LIST OF FIGURES x

LIST OF ABBREVIATIONS xiii

CHAPTER 1: INTRODUCTION 1

1.1 Background of the Study 1

1.2 Problem Statement 2

1.3 Objectives 3

1.4 Scope 4

CHAPTER 2: LITERATURE REVIEW 5

2.1 Introduction 5

2.2 Material Handling Equipment – Automated Guided Vehicle 6

2.2.1 Introduction to Material Handling Equipment Technology 6

2.2.2 Automated Guided Vehicle (AGV) system 6

2.2.3 Description of an AGV system 7

2.3 AGV Structure Design 8

2.3.1 Steel bridge background 9

2.4 Steel bridges main structural design 11

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2.4.1 Pratt truss bridges 12

2.4.2 Warren truss bridges 16

2.4.3 Other types 17

2.5 Design comparison 18

2.6 Software Tools 20

2.6.1 Structural Design and Simulation 20

2.6.1.1 CATIA 20

2.6.1.2 Hyperworks solidThinking 21

2.6.1.3 SpaceClaim 22

CHAPTER 3: METHODOLOGY 24

3.1 Introduction 24

3.2 Overall Process 24

3.3 Process Flow Chart 25

3.3.1 Design Process Flow 26

3.3.2 Design Concept and Brainstorming 27

3.3.3 Bill of Materials 29

3.3.4 CAD Design 31

3.3.5 CAE Simulation Test 32

3.3.6 Fabrication 32

3.4 System Architecture 32

3.5 Calculation 33

3.5.1 Force 33

3.5.2 Rolling Resistance 33

3.5.3 Gradient Resistance 34

3.5.4 Total Tractive Effort 34

3.5.5 AGV total tractive effort calculation 35

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3.6 Material of Model 36

3.7 Design Space 36

3.8 Non-Design Space 36

CHAPTER 4: RESULTS AND DISCUSSION 38

4.1 Introduction 38

4.2 Finite Element Analysis 38

4.2.1 General Procedure on FEA 38

4.2.1.1 Step 1: CAE Driven Structurally Efficient 39

Conceptual Design

4.2.2 Conceptual Design Process Flow 41

4.2.2.1 Conceptual design preparation 42

4.2.2.2 Create design space 42

4.2.2.3 Topology optimization 43

4.2.2.4 Result interpretation 44

4.2.2.5 New structurally efficient conceptual design 45

4.2.3 Design Optimization 46

4.2.3.1 Modify/ prepare design based on previous iteration result 47

4.2.3.2 Design analysis 47

4.2.3.3 Design optimization 47

4.2.3.4 Design completed 47

4.3 Design process 48

4.3.1 Design Iteration #1 48

4.3.2 Design Iteration #2 50

4.3.3 Design Iteration #3 52

4.3.4 Design Iteration #4 53

4.3.5 Design Iteration #5 55

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4.3.6 Design Iteration #6 56

4.3.7 Design Iteration #7 58

4.3.9 Final Design 59

4.4 Vehicle structure mass 60

4.5 Von Mises Stress 61

CHAPTER 5: CONCLUSION 63

5.1 Future studies 63

REFERENCES 65

APPENDICES 67

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LIST OF TABLES

3.1 The Bill of Material (B.O.M) list 29

3.2 Material properties of AGV frame 36

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LIST OF FIGURES

1.1 Example of AGV in the market 3

2.1 Autonomous guided vehicle system in a factory 7

2.2 Guide path of an AGV 8

2.3 A Pratt truss construction 12

2.4 A Pratt truss with addition of top polygon arc 13

2.5 A Parker truss but with exactly 5 pieces to the top chord 13

2.6 A lenticular truss construction 14

2.7 A Baltimore truss construction 15

2.8 Pennsylvania truss construction 15

2.9 A Whipple truss configuration 16

2.10 A construction of Warren truss 17

2.11 A double Warren truss configuration 17

2.12 A bowstring truss construction 18

2.13 A Fink truss configuration 18

2.14 Steel bridges construction trusses 19

2.15 Example drawing use CATIA software 21

2.16 Example of simulation results 22

2.17 SpaceClaim interface window 23

3.1 Flow chart for design and development of the structure 26

3.2 The first concept design 27

3.2 The first concept design 28

3.4 The third concept design 28

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3.5 An actual design of the AGV based on the concept design 31

3.6 System architecture conceptual model 33

3.7 The AGV wheel climb a slope 35

3.8 Non-design space for the AGV 37

4.1 A typical design process flow 39

4.2 CAE driven design process flow 40

4.3 The conceptual design process flow 41

4.4 Conceptual design of the AGV 42

4.5 The design space of the AGV 43

4.6 Topology optimization run window 44

4.7 The optimized design space 45

4.8 The imported model to SpaceClaim from solidThinking Inspire result 46

4.9 Design optimization flow 46

4.10 Design #1 with load path iteration new conceptual design 48

4.11 Von Mises Stress design #1 49

4.12 Design #1 optimization 49

4.13 Design #2 with load path iteration #1 50

4.14 Von Mises Stress for design #2 51

4.15 Design #2 optimization 51

4.16 Design #3 with load path iteration #2 52

4.17 Design #3 Von Mises Stress 52

4.18 Optimization design #3 53

4.19 Design #4 with load path iteration #3 53

4.20 Design #4 Von Mises Stress 54

4.21 Design #4 optimization 54

4.22 Design #5 with load path iteration #4 55

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4.23 Von Mises Stress value for design #5 55

4.24 Design #5 optimization 56

4.25 Design #6 with load path iteration #5 56

4.26 Von Mises Stress vale for design #6 57

4.27 Design #6 optimization 57

4.28 Design 7 with load iteration #6 58

4.29 Von Mises Stress for design #7 59

4.30 Final design 59

4.31 The AGV structure mass distribution 60

4.32 Von Mises Stress 61

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LIST OF ABBREVIATION

AGV - Autonomous Guided Vehicle

AGVS - Autonomous Guided Vehicle System

BOM - Bill of Materials

CAE - Computer Aided Engineering

CAD - Computer Aided Design

JIT - Just In Time

WIP - Work In Progress

STI - solidThinking Inspired

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CHAPTER 1

1.0 INTRODUCTION

1.1 Background of the Study

For the last 10 years, the world economic growth rapidly and have been becomes

the battle stage between the industrial companies. Because of this particular

phenomenon, most companies lower their price by increasing their production quantity

increase their sales in order to get the same profit margin. At this point, the situations

affect the workers. When the production increases, the quantity parts supply also

increase. The increasing of workload workers makes themselves stress and fatigue. This

lead to the increasing of worker turnover rate for operating the production. This situation

leads to the autonomous guided vehicle (AGV) implementation to support part supply

operation.

30 to 80 percent of the total cost of production efficient material handling is

critical to a manufacturing facilities success. According to Jones et al. (1998)

Autonomous guided vehicle systems (AGVS) have become a key component for factory

modernization and increased productivity with the recent advances in microprocessor

and control system.

The main concept of an autonomous guided vehicle (AGV) grasps all transport

systems which are capable of functioning without driver assistance. When first

introduced to industry, the AGV was in competition with driver operated material

handling system such as pallet carts, fork lifts and tow tractors. However, since

microprocessor technology has evolved, the capabilities and types of AGV system

improved from time to time. Nowadays AGV is now in direct competition with other

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forms of industrial transportation such as roller conveyors, belt conveyors and chain

conveyors.

According to Ali et al. (2010), AGV applications within the United States have

grown remarkably during the last decade and are currently expanding at a 30% annual

rate. AGVs can be found in nearly every sectors of industry. AGVs implementations are

limited only by their operational applications and economic activity.

AGV is introduced to support the supply system however the initial investment

is very high and it cannot convince a certain company to invest such amount of money

for the system. In this project, the focus research is more on a low cost of AGV with

more energy efficient. Energy consumed is more on carrying the load, not for carrying

its heavy body. This project is inspired by the ability of the ants, which can lift up to

5000 times of their own body weight as viewed in Your Universe Online website at

<http://www.redorbit.com/news/science/1113068168/ant-neck-joint-helps-lift-weight-

021114/>.

1.2 Problem Statement

Generally in Malaysia, there is no Autonomous Guided Vehicle (AGV) that

integrated with automated part racking system, which use automatic roller for easy to

dispatch item to the workstation. Few AGV have been introduced in the market in few

recent years such as TransCar Automated Guided Vehicle, INTELLICART-Automated

Guided Vehicle, and Toyota's Automated Guided Vehicles (AGVs) that can carry extra

load is available at http://www.toyotaforklift.com/category/otherproducts.aspx but most

of the AGV design are heavy and bulky and the application is only focused on carry the

parts from point A to point B. The price range is also quite expensive which can reach

around RM 300k to RM 500k for the development of an AGV system.

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Figure 1.1: Example of AGV in the market (http://www.swisslog.com)

1.3 Objective

It is known that the late modern technology, there have been changes in

industrial sector in terms of increased number of production, heavier supply material,

introduction of new machine and techniques. Because these changes are far beyond the

company experience, prevailing design method of AGV for industrial sector seem to

have very limited success.

In this project, the objective is focus on:

1) Design of economic lightweight AGV. The research is focused mainly on parts

supply using polyboxes.

2) Analyse the structural strength through CAE simulation.

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1.4 Scope

The scope of this project starts from designing the structure of the AGV and

testing of the AGV system. There are two main parts which must achieve to ensure the

AGV can work well. The first part is the AGV body design and the second part is the

total load that the AGV can hold. Overall scopes of project are as stated below:

1) Design the model of the AGV by using CATIA and SpaceClaim.

2) Optimize the design to withstand desire load.

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CHAPTER 2

2.0 LITERATURE REVIEW

2.1 Introduction

This section will discuss about the fundamentals, theories and concepts of this

project in detail. Besides that, it also explains about the perspective, components and

method that will be used in this project. The concept of the AGV that will be discussed

is more about design and comparison.

2.2 Material Handling Equipment – Automated Guided Vehicle

In the early 1950s, the material handling industry was still growing due to the

increase in manufacturing caused by World War II. In an attempt to make good business

even better, a group of material handling distributors gathered and discovered many of

them were facing similar difficulties. These companies decided to join forces and form

an association as a way of mutually benefitting all members. In 1954, a meeting was

held between eight distributors at the Morrison Hotel in Chicago, IL. That meeting

marked the certain topics referring to the material handling industry, including industrial

trucks, engineered systems and conveyors, storage and handling equipment,

warehousing, storage rack, logistics and other related industry sectors.

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2.2.1 Introduction to Material Handling Equipment Technology

Material Handling Institute define material handling as the movement of bulk

packaged and individual goods, as well as their in process and post process storage, by

means of manual labor or machine within the boundaries of a facility.

The objective of material handling is the efficient movement of goods for on-

time delivery of correct parts in exact quantities to desired locations in order to minimize

handling costs. It is not uncommon to have parts moving around a factory several

kilometers before proceed to their shipment. Manufacturing factories must eliminate all

unnecessary parts movements, as well as in process section, for just-in-time (JIT)

production. There are several types of material handling equipment according to the

movement mode such as above-floor transportation, on-floor transportation and

overhead transportation.

2.2.2 Automated Guided Vehicle (AGV) system

Material handling is an important factor of any production system. Material

handling systems have been extensive since the beginning of mass production, either as

mechanical system, manual system, or in more recent years as fully automated system.

Technology advances every day and need for flexibility and reliability to increase

attention on automated material handling systems. The use of AGV systems are

becoming accepted in today’s industries. AGVs have become increasingly popular in

terms of horizontal material handling transportation system. They are particularly useful

where products need to handled carefully or the environment is potentially dangerous to

workers such as IC chips, voltage cables, flammable and radioactive materials.

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Figure 2.1: Autonomous guided vehicle system in a factory (www.bluebotics.com)

2.2.3 Description of an AGV system

AGV system is an advanced material handling system that involves one or more

driverless vehicle each following a guide path and controlled by an-off board

microprocessor or computer. AGV are typically used to carry parts supply in production

and assembly operations. The advantages of AGVs include reliable, flexibility in

adapting to changes in material flow, improved position accuracy, easily expandable

layout and system capacity, reduced handling damage and automated interfaces with

other system. An AGV reduce in the labor force because it allows automation of a

certain portion of material handling which is also results in an increase in the efficiency

of the material handling operation, thus resulting in better utilization of the work force

and processing equipment.

The efficient of material handling system also helps in improving quality and

reducing mistakes. The improved system results in increased worker satisfaction as it

change the material time arrival rate to suit the workers pace. Sezen (2003) gives out

main advantage of an AGV system is real-time control of material handling. This helps

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in identification of the parts, the path they travel and the vehicles they travel in, resulting

in lower Work in Progress (WIP) storage, lower inventory costs, reduce delay and better

response to demands.

The main disadvantage of an AGV based on material handling system is its price

tag. The high cost of the control software, development and the number of vehicles

required in a single system cut back the wide usage of AGVs as material handling

systems. Other limitations of an AGV include necessity for polished floor surfaces for

smooth operation of the AGVs. A guide path has stability problems and restriction such

as height of metal floors that must be crossed. Obstacles in the facility layout and slope

gradients are other restriction the need to be overcome when designing the guide path

for the AGVs. It can be seen from above that though the AGV has a number of

advantages, it also has its share of disadvantages and may not be applicable in all cases.

Figure 2.2: Guide path of an AGV (www.news.thomasnet.com)

2.3 AGV Structure Design

Designing and drawing parts is an important part of AGV development. To

design the structure of AGV there are several patterns need to refer. Each of the design