Network And Controls Of Servomotors.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

NETWORK AND CONTROLS OF

SERVOMOTOR

Report submitted in accordance with partial requirements of the Universiti Teknikal Malaysia Melaka for the Bachelor of Manufacturing Engineering

(Robotics & Automation)

Teng Guat Theng

Faculty of Manufacturing Engineering April 2008

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS LAPORAN PSM

JUDUL:

NETWORK AND CONTROLS OF SERVOMOTOR SESI PENGAJIAN:

Semest er 2 2007/ 2008 Saya TENG GUAT THENG

mengaku membenarkan laporan PSM / t esis (Sarj ana/ Dokt or Falsaf ah) ini disimpan di Perpust akaan Universit i Teknikal Malaysia Melaka (UTeM) dengan syarat -syarat kegunaan sepert i berikut :

1. Laporan PSM / t esis adalah hak milik Universit i Teknikal Malaysia Melaka dan

penulis.

2. Perpust akaan Universit i Teknikal Malaysia Melaka dibenarkan membuat salinan

unt uk t uj uan pengaj ian sahaj a dengan izin penulis.

3. Perpust akaan dibenarkan membuat salinan laporan PSM / t esis ini sebagai bahan

pert ukaran ant ara inst it usi pengaj ian t inggi.

4. *Sila t andakan (√)

SULIT

TERHAD

TIDAK TERHAD

(Mengandungi maklumat yang berdar j ah keselamat an at au kepent ingan Malaysia yang t ermakt ub di dalam AKTA RAHSIA RASMI 1972)

(Mengandungi maklumat TERHAD yang t elah dit ent ukan oleh organisasi/ badan di mana penyelidikan di j alankan)

(TANDATANGAN PENULIS) Alamat Tet ap: 1036, Taman Sri Kot a,

Jalan Kuala Kedah, 06600 Alor St ar, Kedah.

Tarikh: _______________________

(TANDATANGAN PENYELIA) Cop Rasmi:

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DECLARATION

I hereby declare that this report entitled “NETWORK AND CONTROLS OF

SERVOMOTOR” is the result of my own research except as cited in the references.

Signature :

Author’s Name : NETWORK AND CONTROLS OF

SERVOMOTOR

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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). The members of the supervisory committee are as follow:

Mr. Ahmad Yusairi Bin Bani Hashim

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iii

ABSTRACT

The project is discussed about the network and controls of servomotor. Actually, this report is divided into two parts, the first part is discussed about the proposal of the project and the second part is discussed about the project implementation. This project totally contains six chapters starting from introduction, literature review, methodology, results, discussion and the last one is conclusion. For the first chapter, it will describe about the title of the project, objective, problem statement, scope, organization of the project and expected outcomes. The main objective of this project is to install servo motors networks to controller and to verify servomotor controls. While the second chapter is discusses about literature review. The literature search is performed to study, analysis and design for this project. The sources of this chapter can gain from internet, journal, book, magazine and etc to support the components that related with the projects. The next chapter is methodology. This chapter is discusses about the steps or procedures that used to achieve the objective of this project. Actually, in this project a simple wire connection should be done to connect the Omron PLC to the SMARTSTEP Servo Driver and then connect the SMARTSTEP A-series Servomotor. The controller is using the CX programming to control the movement of servomotor lead screw application. Therefore, some experimental results are obtained and described in chapter four. Then, the following chapter is discusses about the result, problems and suggestion to overcome the problems. Finally, the overall project and its achievements are concludes in chapter six.

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ABSTRAK

Projek ini adalah menerangkan tajuk tentang “network and controls of servomotor”. Sebenarnya, laporan in adalah terbahagi kepada dua. Pertama, adalah menerangkan perkara-perkara yang berkaitan dengan laporan cadangan dalam projeck ini. Kedua, adalah menerangkan perkara-perkara tentang projek pelaksanaan. Projek melingkungi enam bab yang bermula dari pengenalan, kajian ilmiah, metodologi, keputusan, perbincangan dan berakhir dengan kesimpulan. Bagi bab satu, ia adalah untuk menerangkan tajuk projek, objektif, pernyataan masalah dalam projek ini dan juga jangkaan hasil. Objektif yang utama dalam projek ini adalah untk memasang rangkaian servomotor kepada sesuatu pengawalan unit dan juga mengesahkan kawalan servomotor. Manakala, bab kedua adalah menerangkan tentang kajian ilmiah. Bab ini adalah mempersembahkan kepada kajian, alisasi, dan lakaran dalam projek ini. Maklumat-maklumat yang berkaitan dengan bab ini boleh dicari melalui internet, jurnal, buku, majalah dan sebagainya untuk menyokong dan menerangkan komponen-komponene yang berkaitan dengan projek ini. Bab yang seterusny ialah metodologi. Bab ini menerangkan langkah atau prosedur yang digunakan untuk mencapai objektif yang dinyatakan sebelum ini. Sebenarnya, dalam projek ini, sesuatu sambungan wayar yang mudah harus disambungkan untuk menyambung Omron PLC kepada SMARTSTEP Servo Driver dan kemudian sambung kepada SMARTSTEP A-series Servomotor. Pengawalan yang digunakan itu adalah menggunakan CX programming untuk mengawal pergerakan servomotor yang terletak dalam lead screw mekanisma. Oleh itu, sesetengah keputusan kajian didapatkan dan ia menerangkan dalam bab ke-4. bab yang seterusnya menerangkan keputusan, masalah dan cadangan bagi projek ini. Akhirnya, keseluruhan projek dan pencapaiannya adalah menerangkan dalam chapter yang ke-enam.

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DEDICATION

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ACKNOWLEDGEMENTS

It gives me utmost pleasure to express my gratitude to who have directly or indirectly contributed to the fruition of the compilation. They include; My supervisor, Mr. Ahmad Yusairi bin Bani Hashim. Thanks for all the guidance and critics given to me directly or indirectly, and also his scarification in time to teach and explain to me without a word of complains. My family, who inspired me weather through the storm and carry on, and last but not least lecturers, friends and relevant personnel who helped in one way or another.

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vii

Declaration i

Approval ii

Abstract iii

Dedication v

Acknowledgement vi

Table of Contents vii

List of Figures xii

List of Tables xv

List of Abbreviations, Symbols, Sign xvi

1.0 INTRODUCTION 1 1.1 Objective 2

1.2 Statement of Problems 2 1.3 Scope 3 1.4 Organization 3 2.0 LITERATURE REVIEW 4 2.1 Programmable Logic Controller (PLC) 5

2.1.1 PC Hardware Structure 6 2.1.2 Input/ Output System 7 2.1.3 Memory Units 8 2.1.4 External Data Communications 9

2.1.5 PLC Programming 10 2.2 Servo Motor 12 2.2.1 Introduction to the Servo Motor 12

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2.3 Wire 17

2.3.1 Standard Wiring Colours 17

2.3.2 Gate Rating 19

2.3.2.1 Detailed Instructions for using the Wire Size Calculator 20

2.3.2.2 Full-Load Currents in Amperes, Single-Phase

Alternating-Current Motors (From 1999 NEC) 21

2.3.2.3 Full-Load Current Three-Phase Alternating-Current

Motors (From 1999 NEC) 22

2.4 Application Formula 26

2.4.1 Angular Distance 26

2.4.2 Angular Velocity 26

2.4.3 Torque 27

2.4.4 Mass Moment of Inertia 28

2.4.5 Torque Motor 31

2.5 Control System 31

2.5.1 Response Characteristics and System Configuration 32

2.5.1.1 Input and Output 32

2.5.1.2 Open-Loop Systems 33

2.5.1.3 Closed-Loop (Feedback Control) Systems 34 2.5.2 Control Engineering: Analyze and Design 36

2.5.2.1 Transient Response 37

2.5.2.2 Steady-State Response 37

2.5.2.3 Stability 38

3.0 METHODOLOGY 40

3.1 Methodology Flow Process Chart 41

3.2 Detail Description of Methodology Flow Chart 42

3.3 The Design Process 44

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3.4 The design process 47

3.5 Simulation (Calculation) 52

4.0 RESULT 54

4.1 Mechanical part 56

4.1.1 Solid Work 56

4.2 Control box 58

4.2.1 Solid Work 58

4.2.2 Electrical Wiring 59

4.3 Programmable Logic Controller (PLC) 60

4.3.1 Ladder Diagram 60

4.3.2 Circuit Diagram 63

4.4 Bill of Material (BOM) 65

5.0 DISCUSSION 67

5.1 Mechanical Part 68

5.1.1 Lead Screw mechanism 68

5.1.2 Bracket for Servomotor 69

5.1.3 Selection of Coupling 71

5.2 Control box for Servo driver 72

5.2.1 Electrical Circuit (IEC Standard) for Control Box 72

5.2.2 The Function of electrical Diagram 73

5.2.3 Testing circuit for Control Box 74

5.3 Programmable Logic Controller 77

5.3.1 Ladder Diagram (CX-Programmer) 77

5.3.2 Electrical circuit between PLC and Servo Driver 80

5.3.3 Testing the PLC Training Kit 81

5.4 Components Analysis 82

5.4.1 Permissible Buckle Load and Tensile Compressive Load 82

5.4.2 Driving Torque 85

5.4.3 Servomotor Position 86

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5.5.1 Servomotor Feedback Controller 88

5.5.2 Transfer Function for Servomotor 90

6.0 SUMMARY AND CONCLUSION 93

6.1 Summary 93

6.2 Conclusion 94

LABORATORY TASK 95

REFERENCE 100

APPENDICES

APPENDIX A

A-1 Connection diagram of PLC, servo driver and servomotor A-2 Wiring: Connector Pin Allocations (PLC)

APPENDIX B

B-1 Servomotor (R7M-A40030)

B-2 Servo Driver (R7D-AP04H)

B-3 Programmable Logic Controller (OMRON SYSMAC CJ1M-CPU22)

APPENDIX C-1

C-1.1 Test waveforms used in control systems C-1.2 Response of a position control system showing effect of high

and low controller gain on the output response

APPENDIX C-2

C-2.1 Laplace Transform Table C-2.2 Laplace Transforms Theorems

APPENDIX C-3

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C-3.2 Block diagram of series RLC electrical network

C-3.3 Force-velocity, force-displacement, and impedance translational relationships for springs, viscous dampers, and mass

C-3.4 a. Mass, spring, and damper system; b. block diagram C-3.5 Torque-angular velocity, torque-angular displacement, and impedance

rotational relationships for springs, viscous dampers, and inertia

C-3.6 a. Physical system; b. schematic; c. block diagram C-3.7 a. Torques on J2 due only to the motion of J2; b. torques on J2 due

only to the motion of J1 c. final free-body diagram for J2

APPENDIX D

D-1 HIWIN Ball Nut Type FSC

D-2 Standard Ball Screw Length

APPENDIX F

F-1 Lead Screw Mechanism

F-2 Servomotor and L-Bracket

F-3 Programmable Logic Controller (PLC)

F-4 PLC and PLC training Kit

F-5 Ball Screw and Bearing

F-6 Structure

F-7 E-stop button and Indicator light

F-8 Star/Stop button

F-9 Flexible coupling

F-10 Engineering drawing for servomotor bracket 1 F-11 Engineering drawing for servomotor bracket 2

APPENDIX G

G-1 Coupling

APPENDIX H

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LIST OF FIGURES

2.1 PLC – I/O structure 6

2.2 A typical PLC structure 7

2.3 PLC communications 7

2.4 Networked PLCs 9

2.5 PLC programming elements 10

2.6 PLC programming elements 11

2.7 Continuity 11

2.8 A Simple Ladder Logic Diagram 12

2.9 The duration of the pulse dictates the angle of the output shaft 13 2.10 Illustration of Servomotor Identifying the Armature 14

2.11 Examples of Duty Cycle Calculation 14

2.12 Typical dc servo motor system with either encoder or resolver 16 feedback. Some older servo motor systems use a tachometer and

encoder for feedback

2.13 BS 7671: 2001 Amendment No 2: 2004 18

2.14 Example of conductor marking at the interface for additions and 19 alterations

2.15 Angular velocity 27

2.16 Right hand rule direction of torque 28

2.17 Simplified description of control system 31

2.18 Elevator response 32

2.19 Block Diagram of Control System: Open-Loop System 33 2.20 Block Diagram of Control System: Closed-Loop System 35

3.1 Methodology flow Chart 41

3.2 Ball Screw Assembly 44

3.3 Types of Ball Screw Starts 45

3.4 Types of Ball Bearing 47

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xiii

4.1 Final layout 55

4.2 Assemble of servomotor with lead screw mechanism by using coupling 55

4.3 Isometric 3D view for layout of project 56

4.4 Top view for 3D drawing of layout project 57

4.5 Front and side view for 3D drawing of layout project 57 4.6 Assemble of servomotor with lead screw mechanism by using coupling 57

4.7 Control Box of the servo driver 58

4.8 The solid work drawing for control box. 58

4.9 The electrical diagram for control box that draw by using 59 Automation Studio

4.10 Timer Base Ladder diagram of PLC to move the servomotor and lead 60 screw mechanism in CW and CCW direction

4.11 Normal jog Ladder diagram of PLC to move the servomotor and lead 62 screw mechanism in CW and CCW direction

4.12 The circuit diagram for the PLC and SMARTSTEP servo driver 63 4.13 Wire connection of the PLC and SMARTSTEP servo driver 64 4.14 Description the wiring connection for box that shows in figure 4.12 64

5.1 Assemble of servomotor and lead screw 69

5.2 L-brackets and support of the servo motor 69

5.3 A sample drawing for L-bracket 70

5.4 Coupling that used to two joining shaft for ball screw and servomotor 71

5.5 Electrical Diagram for control box 72

5.6 Testing the circuit of the control box 75

5.7 The ladder diagram for servomotor which move in clockwise direction 78 5.8 The ladder diagram for servomotor which move in CCW direction 79 5.9 The circuit diagram for the PLC and SMARTSTEP servo driver 80 5.10 The simple programming that use to test the function of PLC and 81

Training Kit

5.11 The testing result 82

5.12 Mounting Method for Ball Screw 83

5.13 Driving Torque Required By the Ball Screw to Move a Load 85

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5.15 A Servomotor Feedback Controller 88

5.16 A Servomotor Feedback Controller 89

5.17 A Combination System Model 89

5.18 Servomotor (a) Schematic; (b) Block Diagram 90

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LIST OF TABLES

2.1 Full-Load Currents in Amperes, Single-Phase Alternating-Current 22 Motors

2.2 Full-Load Current Three-Phase Alternating-Current Motors 23

2.3 Wire Gage 25

2.4 List of Moments of Inertia 29

4.1 Standard Part BOM for Project 65

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LIST OF ABBREVIATIONS, SYMBOLS, SPECIALIZED

NOMENCLATURE

PLC - Programmable Logic Controller RTOS - Real Time Operating System

I/O - Input/ Output

CPU - Central Processing Unit

DC - Direct Current

AC - Alternating Current

V - Voltage

ROM - Read-Only Memory

RAM - Random-Access Memory

EPROM - Erasable Programmable Read-Only Memory

EEPROM - Electrically Erasable Programmable Read-Only Memory LAN - Local Area Networks

LLD - Ladder Logic Diagrams

ST - Structured Text

FBD - Function Block Diagrams SFC - Sequential Flowcharts IL - Instruction Lists

IEE - Institution of Electrical Engineers

IET - Institution of Engineering and Technology IEC - International Electrotechnical Commission

BS - British Standard

NEC - National Electrical Code AWG - American Wire Gage

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CHAPTER 1 INTRODUCTION

Servo motors are best known for their rapid acceleration and deceleration capability, made possible by delivering high-peak torque in conjunction with a high torque-to-inertia ratio.Servo motors are famous for their high dynamic response and precision accuracy in traditional motion control applications, such as machine tools and robotics.

Nowadays, many servomotors are controlled by using some controllers such as PLC (Programmable Logic Controller), PAC (Programmable Automation Controller) and etc. Actually, this project will present about the network and controls of servomotors. The controller that will use in this project to control the servomotor is Omron brand’s PLC.

The purpose of this project is to install servomotors networks to controllers according to the connection diagram on the operation manual. After installed the servomotor to PLC, then the following step is verify the servomotor controls. The focus of this report is on system investigation with some analysis in control engineering such as speed, stability, movement and etc.

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1.1 Objective

The purpose of this project is to install complicated servo motors networks to controllers according to the connection diagram on the operation manual. Through this project, students can understand about the equipment, device and component that used in this project. All this information and knowledge is very important to easier student install the complicated servomotors network to controller. After complete install the servomotor to controller, student should write a PLC’s program to control the servomotor. Through this, student will know how to apply the PLC programming to execute the servomotor. After that, student should verify the servomotor and investigate some analysis in control engineering such as speed of motor, stability of motor, movement of motor.

1.2 Statement of Problems

There have five sets of servomotor with controller are provided in this project. The servomotor does no function as a result of incomplete networking and installation. So, the important thing that should do in this project is find some suitable electrical connector or device to connect the wiring from PLC to servomotor. The electrical device that mention just now is start/stop button, emergency stop, relay, wire and so on. To connecting all the wiring of this project, student should study out the diagram that provided by the manufacturer (refer to Appendix A). Through this diagram, only students will know how to install and network the motor.

After connecting all the electrical circuit of servomotor and PLC, the control strategies shall verify the correct system integration. The control strategies such as movement, speed, pulse and so on are used to determine the capability of the servomotor. Beside that, the application of servomotor which suitable used in laboratory session should apply in this project. In this project, Lead Screw Mechanism is chosen as a laboratory model to show out the capability of servomotor

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1.3 Scope

The focus of this report is on system investigation with some analysis in control engineering which is the engineering discipline that focuses on mathematical modeling of systems of a diverse nature, analyzing their dynamic behavior, and using control theory to create a controller that will cause the systems to behave in a desired manner. In this project, the control engineering such as speed, movement and transient response should take in consider to obtain an excellent result. After connecting all the wire connection and also finish assemble the mechanical part of this project, the analysis of control engineering should take in account to get the perfect result.

1.4 Organization

The organization in this report is as follows; first, chapter one of this report, describe the background, objective and scope of the project, as well as the organization section. Second, chapter two provides the literature review about the device that used in this project and also some theoretical concept in engineering field which related to this project. Next, chapter three presents the methodology of the project that including the description of methodology, material selection and process involved in this project. Chapter four, list out all the result that gain in this project such as list of part, description of the structure and analysis result. Chapter five discuss the improvement that should done, target application of the project and give some recommendations on this project. Finally, chapter six serves as the conclusion of the project.

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CHAPTER 2 LITERATURE REVIEW

This chapter discusses about the literature discourse and review of structural analysis and some definition of the components used in this project such as PLC (Programmable Logic Controller), servomotor, CX programmer and etc. through the world, there have many difference sources and researches about the concept, design and implementation of the servomotor by using PLC. It also included the investigation of what others have done in this area. This study included the areas of mechanical, electric, electronic and software development. Literature reviews are based of information that obtained from various sources, articles, technical reports, general reports, websites, books and personal communication.

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2.1 Programmable Logic Controller (PLC)

Nowadays, almost all control applications require switching (on or off) which contain of various outputs as a function of a number of inputs [1]. The programmable logic controller is known as logic control or switching control. This switching control are quite simplicity that why it attractive for use in automatic machines where there is a requirement for the machine to follow a set sequence of operations to gives rise to the term sequential control by using switching control.

Normally, a PLC is an industrialized dedicated microcontroller. It is operation based primarily on sequential control of a process. Its Real Time Operating System (RTOS) scans a program in a repetitive cycle and actions are taken (outputs set) depending on logical relationships (specified by the programmer) between the inputs [1].

In fact, a PLC or Programmable Controller is a digital computer used for automation of industrial processes, such as control of machinery on factory assembly lines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed or non-volatile memory. A PLC is an example of a real time system since output results must be produced in response to input conditions within a bounded time, otherwise unintended operation will result [2].

The PLC has been part of manufacturing automation for over two decades, replacing the hard-wired relay logic controllers (Figure 2.1). For smaller-scale, event-driven processes and machines with limited I/O points, stand alone PLCs are the controller of choice. PLCs are rugged, relatively fast, and low cost with excellent sequential control performance [3].

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Figure 2.1: PLC – I/O structure [3]

Recently, PLCs have been gaining popularity on the factory floor and it will probably remain predominant for some time to come. Most of this is because of the advantages they offer. The advantages of the PLCs are:

§ Cost effective for controlling complex systems

§ Flexible and can be reapplied to control other systems quickly and easily.

§ Computational abilities allow more sophisticated control.

§ Trouble shooting aids make programming easier and reduce downtime.

§ Reliable components make these likely to operate for years before failure.

2.1.1 PLC Hardware Structure

A PLC is an industrial computing device that continuously and sequentially checks its input ports to determine the most recent events that have occurred within the system it is controlling, and it activates or deactivates its output ports to allow or disallow other events to happen within the system as show in Figure 2.2. The core unit of the PLC, as with any other computingdevice, is the central processing unit (CPU). The CPU controls all the operations within the PLC based on instructions specified by the user in the form of a program stored in its memory. The CPU

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CHAPTER 1

INTRODUCTION

Servo motors are best known for their rapid acceleration and deceleration capability, made possible by delivering high-peak torque in conjunction with a high torque-to-inertia ratio. Servo motors are famous for their high dynamic response and precision accuracy in traditional motion control applications, such as machine tools and robotics.

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