Design And Development Of An Embedded Controller For Robotic Application.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA 4

FAKULTI KEJURUTERAAN ELEKTRIK 5

6 7

PROJEK SARJANA MUDA 8

( PSM 2) 9

BEKU 4983 10

11 12 13

DESIGN AND DEVELOPMENT OF AN EMBEDDED 14

CONTROLLER FOR ROBOTIC APPLICATION 15

16 17

LIM WEE TECK 18

MAY 2008 20

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“I hereby declared that I have read through this report and found that it has 10

comply the partial fulfillment for awarding the degree of Bachelor of 11

Electrical Engineering ( Control, Instrumentation and Automation )” 12

13 14

Signature : 15

Supervisor’s Name :En. MOHD SHAHRIEEL Bin MOHD ARAS 16

Date :7 May 2008

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DESIGN AND DEVELOPMENT OF AN EMBEDDED CONTROLLER FOR ROBOTIC APPLICATION.

LIM WEE TECK

This Report Is Submitted In Partial Fulfillment Of Requirements For The Degree of Bachelor In Electrical Engineering

(Control, Instrumentation and Automation)

Fakulti Kejuruteraan Elektrik Universiti Teknikal Malaysia Melaka

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“I hereby declared that this report is a result of my own work except for the excerpts that have been cited clearly in the references.”

Signature :

Name : Lim Wee Teck Date : 7 May 2008

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To my dearly loved father and mother To all my teachers and friends

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ACKNOWLEDGEMENTS

I wish to thank my project supervisor, En Mohd Shahrieel Bin Mohd Aras for his guidance and teachings. And also would like to thank both the panels for their guidance.

I would also wish to extend my gratitude to my parents for their support and their understanding.

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ABSTRAK

Penggunaan mesin-mesin untuk menggantikan tenaga kerja yang dibuat oleh manusia pada zaman kini kian meningkat. Ini kerana peggunaan mesin automatik bukan saja dapat meningkatkan produktiviti, mesin juga dapat membuat kerja-kerja yang susah seperti mengangkat benda yang berat atau memateri kaki-kaki cip yang kecil dan padat. PIC, salah satu jenis alat kawalan yang biasa digunakan untuk mengawal mesin automatic. Ia mendapat sambutan yang baik kerana kos yang rendah, skop penggunaan yang luas, dan cara penggunaan yang senang. Dalam laporan ini, akan dibincangkan tentang pembentukan satu lengan robotik serta litar kawalannya menggunakan PIC. Dengan litar kawalan yang sedia ada di pasaran, dibuat semula dengan mengecilkan dan mempadatkan lagi litar itu supaya dapat digunakan dengan penggunaan tempat yang minimum. Selain itu, laporan ini juga akan meliputi penjelasan program yang digunakan iaitu MikroC. MikroC adalah satu alat pembangunan PIC yang menggunakan Bahasa C sebagai bahasa programnya. Untuk lengan robotik, tiga biji servo motor akan digunakan untuk mengerakkan lengan itu sebanyak tiga sudut bebas.

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ABSTRACT

The usage of machine replacing the work done by human in this modern age is increasing rapidly. It is because automated machine can not only increase productivity, it can also do work that are hard to be done by human such as lifting heavy object or soldering the small and complicated leg of a chip. PIC, one of the many types of controller that are used to control automatic machinery. It is popular due to its low cost, wide availability, large user base and an extensive collection of application notes. In this report, will be discussing about the making of a robotic arm and also its control circuit that uses PIC. By referring to an available control circuit in the market, it is then re-design into a smaller and more compact product so that it can be use without taking a big amount of space. Other than that, this report will also discuss on the program used, MikroC. MikroC is a multi-usage development tool for PIC micros that uses C language as its program language. For the robotic arm, three servo motor are used as drivetrain to create a three degree of freedom robotic arm.

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CONTENTS

CHAPTER TITLE PAGE

SUPERVISOR’S VERIFICATION PROJECT TITLE

AUTHENTICATION ii

DEDICATIONS iii

ACKNOWLEDGEMENT iv

ABSTRACT v

CONTENTS vii

LIST OF TABLES x

LIST OF FIGURES xi

LIST OF APPENDIX xiv

LIST OF SYMBOLS AND TERMS xv

1 INTRODUCTION

1.1 Background 1

1.2 Problem Statement 2

1.3 Project Objective 2

1.4 Project Scope 2

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2.1 Introduction 4

2.2 Microcontrollers 5

2.3 Microcontrollers from Microchip 7 2.4 Why Use PIC16F877A Microcontroller 8

2.5 877-TB Project Kit 9

2.6 RHINO Robot XR-3 10

3 THEORY AND DESIGN

3.1 PIC16F877A 12

3.2 Circuit Diagram 16

3.2.1 Main Controller Circuit 16 3.2.2 Input and Output Circuit 17

3.3 MikroC 19

3.4 Servomotor 20

3.5 Robotic Arm Design 22

4 RESULTS

4.1 PCB Controller Board 25

4.1.1 Main PCB Controller Board 25

4.1.2 Additional Board 28

4.2 Controller Board 31

4.2.1 Connection Description 33

4.3 Hardware 35

4.3.1 Base 36

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4.3.3 Gripper 40

4.3.4 Control Box 41

4.4 Software 42

4.4.1 Programming Language 42 4.4.2 Simulation Software 42 4.4.3 Downloader Program 42

5 ANALYSIS

5.1 Experiment 1 44

5.2 Experiment 2 47

5.3 Experiment 3 50

6 CONCLUSION & FUTURE PLANNING

6.0 Conclusion 57

6.1 Future Planning 58

REFERENCE 60

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LIST OF TABLES

TABLE TITLE PAGE

2.0 Various brand of Microcontroller 6 2.1 Specifications of Rhino Robot 11 3.0 Link Parameter for Robotic Arm 24

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LIST OF FIGURES

FIGURE TITLE PAGE

1.0 Methodology Flow Chart 3 2.0 Elements in Microcontroller 5 2.1 PIC from Microchip 7

2.2 877-TB PIC Board 9

2.3 RHINO Robot 10

3.0 PIC16F877A 15

3.1 Controller Circuit Diagram 16 3.2 Input Connections to Push Button 17

Circuit Diagrams

3.3 Output Connections to Srevo Motor 17 Circuit Diagrams

3.4 I/O connections to PIC 1 (Primary) 18 3.5 I/O connections to PIC 2 (Secondary) 18

3.6 Servomotor 20

3.7 Diagram of pulse widths sent to control 21 Servo Motor position

3.8a Robotic Arm Concept 22 3.8b Robotic Arm Concept 22 3.9 Expected Work Space 23 3.10 Details of Robotic Arm Sections 24

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4.1b Bottom Layer of the PCB board 26 4.2a Exact size of top layer PCB 27 4.2b Exact size of bottom layer PCB 27 4.3 PCB layout of the input connection 28 4.4 PCB layout of the output connection. 28 4.5 Secondary Controller Board 28 4.3a Exact size of Input Control Connection PCB 29 4.4a Exact size of Servo Output Connection PCB 29 4.5a Exact size of Secondary Controller PCB 30 4.6 Main Controller Board with Serial Connection 31 4.7 Input and Output Connection Board 31 4.8 Secondary Controller Board 32 4.9 Connections to primary PIC I/O pins 33 4.10 Connections to secondary PIC I/O pins 33 4.11 Output connections to Servo Motor 34 4.12 Input Connections from push button 34 4.13 Overall Robotic Arm Structure 35 4.14 Overall Robotic Arm Structure 35 4.15 The base of the structure 36 4.16 Connection of Base to Arm 1 36 4.17a Interior of the Base 37 4.17b Interior of the Base 37 4.18 Overall Arm Structure 38

4.19 Arm 2 38

4.20 Robotic Arm without Arm 2 39 4.21a Gripper Opened 40

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xiii

4.21b Gripper Closed 40 4.22 Gripper with Rubber Mat 40 4.23 Descriptions of the Gripper 41

4.24 Control Box 41

4.25 PIC Downloader 42

4.26 PIC Downloader ready 43 5.0a Processor Clock Speed = 20MHz 45 5.0b the PWM created is in 200us cycle ( too small ) 45 5.1a Processor Clock Speed = 200KHz 46 5.1b the PWM created is in 20ms cycle (desired) 46 5.2a Created PWM in 20ms cycle 48 5.2b Created PWM in 200ms cycle 48 5.3 Unstable Arm Structure 49 5.4a First PWM generated to Servo Motor 1 51 5.4b Second PWM generated to Servo Motor 1 51 5.5a First PWM generated to Servo Motor 2 52 5.5a Second PWM generated to Servo Motor 2 52 5.6a First PWM generated to both Servo Motor 53 5.6b Second PWM generated to both Servo Motor 53 5.7a First PWM generated to Servo Motor 1 54 5.7b Second PWM generated to Servo Motor 1 54 5.8a PWM generated to both Servo in 200ms cycle 55 5.8b PWM generated to both Servo in 20ms cycle 55 5.9 Positions with mild vibrations 56

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LIST OF APPENDIX

APPENDIX A1 62

APPENDIX A2 64

APPENDIX A3-1 71

APPENDIX A3-2 78

APPENDIX B1 84

APPENDIX B2 85

APPENDIX B3-1 86

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LIST OF SYMBOLS & TERMS

A/D (ADC) Analog to Digital Converter CPU Central Processing Unit CCW Counter Clock Wise

CW Clock Wise

CMOS Complementary Metal–Oxide–Semiconductor D/A (DAC) Digital to Analog Converter

EEPROM Electrically Erasable Programmable read-only memory

IC Integrated Circuit

I/O Input and Output MCU Microcontroller Unit

PC Personal Computer

PCB Printed Circuit Board

PIC Peripheral Interface Controller

PSP Parallel Save Port

PWM Pulse Width Modulation RAM Random Access Memory ROM Read-only Memory

RISC Reduced Instruction Set Computer

USART Universal Synchronous Asynchronous Receiver Transmitter

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INTRODUCTION

1.1 Background

The microcontroller and the robotic application outlined in this project make extensive use of the PIC series of microcontroller from Microchip Technology Inc. In addition to its ability to run programs, the microcontroller has input and output lines (pins) that are used to control motor drive systems, read sensors, and communicate.

A microcontroller is essentially an inexpensive single-chip computer. Single chip means the entire computer system lies within the confines of a silver of silicon encapsulated inside the plastic housing of an integrated circuit. The microcontroller has features similar to those of a standard personal computer. The microcontroller contains a CPU (central processing unit), RAM (random access memory), ROM (read-only memory), I/O (input/output) lines, serial and parallel ports, timers, and sometimes other built-in peripherals such as analog-to-digital (A/D) and digital-to-analog (D/A) converters. The key feature of the PIC is the microcontroller’s capability of uploading, storing, and running a program.

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1.2 Problem Statement

Even thou microcontroller has been widely used especially for industrial purposes, these existing microcontroller is design based on specific purpose and function. This means that its input and output number is fixed, and most controller circuit does not include burner circuit. This is because to prevent any modifications and alterations. As for educational purpose, the size of the existing control circuit can still be modified and reduce in size. And for the application the robotic arm can be build according to needs and does not need to buy an expensive and complex machine.

1.3 Project Objective

To design and development of an embedded controller for robotic applications.

1.4 Project Scope

• To study and determined a suitable controller

• To make a controller circuit board that is small and compact

• To make a controller circuit that integrates both burner circuit and output circuit

• To make a multi function / purpose controller

• To design and build a simple robotic arm with three degree of freedom

• To study and familiarize with C language

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In this project, the whole process will be separated into two parts, part 1 will be the development of the Controller Board while part 2 will be the construction of the Robotic Arm. The process flow is as shown in Figure 1.0 .

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1 2 CHAPTER 2 3 4 5 6 LITERATURE REVIEW 7 8 9 10 2.1 Introduction 11 12

Microcontroller is something that has been widely used and is very common 13

for Electrical Applications. This is because microcontroller is an inexpensive single-14

chip computers, microcontrollers are easy to embedded into larger electronic circuit 15

designs. Their ability to store and run unique programs makes them extremely 16

versatile. For instance, one can program a microcontroller to make decisions and 17

perform functions based on situations and events. The math and logic functions 18

allow the microcontroller to mimic sophisticated logic and electronic circuit. 19

Microcontrollers are incorporated in consumer electronics and are responsible for 20

the “intelligence” in these smart electronic devices. 21

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Microcontroller contains a central processing unit (CPU), random access 4

memory (RAM), read-only memory (ROM), electrically erasable programmable 5

read-only memory (EEPROM), input/output (I/O) port, serial and parallel parts, 6

timer, and other built-in peripherals, such as analog-to-digital converter and digital 7

to analog converter as shown in Figure 2.0 . 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

Figure 2.0: Elements in Microcontroller 23 24 Analogue PWM ROM EEPROM Serial RAM TIMER Parallel CPU CORE

CPU PWM

A/D FILTER Digital PWM Analogue Input Microcontroller

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There are many microcontrollers on the market such as Microchip, Motorola, Atmel, 2

Hitachi and Zilog. The features for these microcontrollers are shown in Table 2.0 . 3

Table 2.0: Various brand of microcontroller 5

Brand Device/type On-Chip Memory Other Features Microchip PIC16F877A 68 byte RAM

64 byte EEPROM

33 I/O pins, 8-bit timer, high current sink, watchdog, timer, RC oscillator, programmable code protection, power saving sleep mode.

Motorola 68HC705KJI 1240 byte OTP 64 byte RAM

15-stage multifunction timer, on chip oscillator, low voltage reset, watchdog, keyboard interrupt, high current I/O port.

Atmel Attiny II 1K byte flash 8-bit timer analog comparator, watchdog, on-chip oscillator, one external interrupt.

Hitachi H8/3640 8K byte ROM 512 byte RAM

Three 8-bit timers, one 16-bit timer, one 14-bit PWM timer, one watchdog, two SCI ports, 8 port 8-bit ADC, 32KHz sub clock generator.

Zilog Z8EOOO 0.5K byte OTP 32 byte RAM

One 16-bit timer, watchdog, 13 I/O pins.

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Microchip Technology’s series of microcontroller is called Peripheral 4

Interface Controller (PIC) chips. These RISC-based MCUs are designed for 5

applications requiring high performance and low cost. PIC is generally assumed as 6

programmable interface controller. PIC is the Integrated Circuit (IC) which was 7

developed to control the peripheral device, dispersing the function of the main CPU. 8

The PIC family includes the 8-pin PIC12Cxxx family, the original 10

PIC16C5x family, the workhorse PIC16Fxxx family, the higher-end PIC 17Fxxx 11

family, and the latest PIC18Fxxx family, which retaining backward compatibility 12

with older members of the PIC line as shown in Figure 2.1. Finally, flash-based PIC 13

is also available. The F in name generally indicates the PIC micro uses flash 14

memory and can be erased electronically. A and C generally means it can only be 15

erased by exposing the die to ultraviolet light. 16

16F877 16F84 19

16F628 12F876 21

Figure 2.1: Some of the PIC from Microchip 22

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1.2 Problem Statement

1.3 Project Objective

To design and development of an embedded controller for robotic applications.

1.4 Project Scope

• To study and determined a suitable controller

• To make a controller circuit board that is small and compact

• To make a controller circuit that integrates both burner circuit and output circuit

• To make a multi function / purpose controller

• To design and build a simple robotic arm with three degree of freedom

• To study and familiarize with C language

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1.5 Methodology

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CHAPTER 2 3

4 5 6

LITERATURE REVIEW 7

8 9 10

2.1 Introduction 11