Design And Analysis Of Automatic Grass Cutter.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

DESIGN AND ANALYSIS OF AUTOMATIC GRASS CUTTER

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

(Robotic and Automation)

by

SITI NOORFATEHAH BINTI ZAINI B050810304

FACULTY OF MANUFACTURING ENGINEERING 2011


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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS LAPORAN PROJEK SARJANA MUDA

TAJUK: Design and Analysis of Automatic Grass Cutter SESI PENGAJIAN: 2010/11 Semester 2

Saya SITI NOORFATEHAH BINTI ZAINI

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 tujuan pengajian sahaja dengan izin penulis.

3. Perpustakaan dibenarkan membuat salinan laporan PSM ini sebagai bahan

pertukaran antara institusi pengajian tinggi.

4. **Sila tandakan ()

SULIT

TERHAD

TIDAK TERHAD

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

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

Alamat Tetap:

No 61, Jalan Permai 3,

Taman Desa Permai, Sg. Lalang, 08100 Bedong, Kedah.

Tarikh: _________________________

Disahkan oleh:

PENYELIA PSM

Tarikh: _______________________

** 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 declare that this report entitled Design and Analysis of Automatic Grass Cutter is the result of my own research except as cited in the references.

Signature : ………...

Author’s Name : Siti Noorfatehah Binti Zaini


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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 (Robotic and Automation) with Honours. The member of the supervisory committee is as follow:

……….. Supervisor


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ABSTRAK

Alat Pemotong Rumput Automatik (AGC) mampu meneruskan tugasan sekiranya wujud halangan di hadapannya dengan bergerak ke arah lain bagi mencapai matlamatnya. Pergerakan ini adalah bagi mematuhi arahan untuk memotong rumput dengan laluan dan dalam perimeter yang khusus iaitu (2.5M (P) x 1.5M(L)) . Projek ini dirancang untuk rekabentuk sebuah Pemotong Rumput Automatik yang kecil dan mudah dibawa supaya boleh melakukan tugas dengan lancar semasa mengelak halangan yang wujud. Sistem Pemotong Rumput Automatik adalah dikawal oleh PIC mikropengawal dan simulasi bagi rekabentuk yang terpilih.


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ABSTRACT

An Automatic Grass Cutter (AGC) has ability to continue it tasks if any obstacle exists in front of its way by moving in another direction to achieve its goals. The movement of AGC is in order to cut grass with path planning and in specific perimeter (2.5M (L) x1.5M (W)). This project is aim to design a small and portable automatic grass cutter that can perform their tasks efficiently while avoiding the obstacle. The system of AGC is control by using PIC microcontroller and the simulation of selected design.


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DEDICATION

Dedicated to my father, Zaini Bin Mahamud and my mother, Siti Faridah Binti Abd. Rahman. To my supervisor, Puan Silah Hayati Binti Kamsani, lecturers and friends


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ACKNOWLEDGEMENT

All Praise to Allah, the Lord of the Worlds, and prayers and peace be upon Muhammad Rasulullah S.A.W, His servant and Messenger. Alhamdulillah, with Allah blessings and guidance, I have completed this project great even though there are many hardship and obstacle along the way.

First of all, I would like to express my appreciation and deep respect to my supervisor, Puan Silah Hayati Binti Kamsani for the guidance and encouraged during finishing this project. Her 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 project.

Thanks to my family, who has been the loveliest advisor to give continually support and inspiration throughout 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. The sacrifice and commitment given towards me earning my Bachelor’s Degree are indescribable and without them, this PSM report will not good completed like this.


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v

TABLE OF CONTENTS

Abstrak i

Abstract ii

Dedication iii

Acknowledgement iv

Table of Contents v

List of Figures viii

List of Tables x

List of Abbreviations xi

1.0 INTRODUCTION 1

1.1 Problem Statement 3

1.2 Objectives 3

1.3 Scope 4

2.0 LITERATURE REVIEW 5

2.1 Autonomous Mobile Robotic and Their Applications 5

2.2 Building Blocks of Robot and Automation 10

2.2.1 Sensors in Mobile Robot 11

2.2.2 Microcontroller 13

2.2.3 Analyzer, Actuator and Drives 14

2.3 Path Planning and Obstacle Avoidance of Robot 18

2.3.1 Sensing the Path Planning 18

2.4 Cutting Mechanism in Lawn Mowing 20

2.4.1 Cutting Formula 21


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vi

3.0 METHODOLOGY 23

3.1 Problem Statement 23

3.2 Project Planning 25

3.3 Research Project 25

3.4 Path Planning 27

3.5 Conceptual design of AGC 28

3.6 Programming the PIC Microcontroller 29

3.7 Simulation Test 32

3.8 Troubleshot and Modification 33

4.0 DESIGN AND ANALYSIS 34

4.1 Conceptual Design 34

4.1.1 Conceptual Design 1 35

4.1.2 Conceptual Design 2 37

4.1.3 Conceptual Design 3 39

4.2 Design Consideration 41

4.3 Selection of Conceptual Design 45

4.4 Analysis of Cutting Mechanism 46

4.4.1 Analysis of Conceptual Design 1 49

4.4.2 Analysis of Conceptual Design 2 50

4.4.3 Analysis of Conceptual Design 3 51

5.0 RESULT AND DISCUSSION 53

5.1 Designing of Automatic Grass Cutter 53

5.2 Analysis of Automatic Grass Cutter 56

5.3 Programming Part 58


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vii

6.0 CONCLUSION AND RECOMMENDATION 63

6.1 Conclusion 63

6.2 Recommendation 64

7.0 REFERENCES 65


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viii

LIST OF FIGURES

1.1 Robot Types 2

2.1 TransCar AGV 6

2.2 AGV systems for industry and distribution 7

2.3 Robomower from Friendly Robotics 7

2.4 Automower from Husqvarna 8

2.5 Trilobite from Electrolux 9

2.6 Trilobite from Electrolux in action 9

2.7 Building Block of Robot 10

2.8 Ultrasonic Range Finder 11

2.9 Photoelectric or IR Beam sensor 12

2.10 Stepper Motor 16

2.11 Example of Solar Panel 17

2.12 Example of a robot sensing obstacles in the path planning 18

2.13 Lawn-mower pattern 20

2.14 Types of blades 20

3.1 Methodology Flow Chart 24

3.2 Gantt Chart PSM 26

3.3 Project Path Planning 27

3.4 Sketching of Automatic Grass Cutter 28

3.5 Flow Chart Programming for PIC microcontroller 30

3.6 Example for Pseudo code 31


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ix

4.1 Conceptual Design 1 35

4.2 Cutting Mechanism of Design 1 36

4.3 Conceptual Design 2 37

4.4 Cutting Mechanism of Design 2 38

4.5 Conceptual Design 3 39

4.6 Cutting Mechanism of Design 3 40

4.7 Map for localization for Automatic Grass Cutter 41

4.8 Wheel for Automatic Grass Cutter 43

4.9 Types of blades uses in AGC and domestic robot 44 4.10 Material arrangement that increasing cutting speed 46

5.1 Circuit Attachment for Automatic Grass Cutter 55

5.2 Programming of DC Motor Operation 59

5.3 IR Sensor Circuit 60


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x

LIST OF TABLES

3.1 Bill of Material (BOM) List 29

4.1 Description Component in Conceptual Design 1 35

4.2 Description Component in Conceptual Design 2 37

4.3 Description Component in Conceptual Design 3 39

4.4 Concept of wheel movement direction 43

4.5 Selection of Design 45

4.6 Feed rate for milling 46

4.7 Specification of 12/24V 1500/3000 RPM Motor 48

5.1 Comparison analysis of Conceptual Design 56


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xi

LIST OF ABBREVIATIONS

ADC - Analog Digital Converter AGC - Automatic Grass Cutter AGV - Automated Guided Vehicles BOM - Bill of Material

DC - Direct Current

GPS - Global Positioning System IC - Integrated Circuit

IR - Infra Red

LED - Light Emitting Diode

PIC - Peripheral Interface Controller PLC - Programmable Logic Controllers PWM - Pulse Width Modulator

RAM - Random Access Memory


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CHAPTER 1

INTRODUCTION

Robot as identified by Capek (1921) is a computer controlled machine that is programmed to move, manipulate objects, and accomplish work while interacting with its environment. Robots are able to perform repetitive tasks more quickly, cheaply, and accurately than humans. The word robot has been used since to refer to a machine that performs work to assist people or work that humans find difficult or undesirable. Capek also defined autonomous robots as robots which can perform desired tasks in unstructured environments without continuous human guidance. Many kinds of robots have some degree of autonomy. Different robots can be autonomous in different ways. A high degree of autonomy is particularly desirable in fields such as space exploration, cleaning floors, mowing lawns, and waste water treatment. Meanwhile mobile can be defined as able to move or be moved easily (Steel, 2003). On the other hand, automatic is when a device, procedure, or system can self-activates (or is executed) under programmed or specified condition and performs specified functions (BusinessDictionary.com) and grass cutter is a device used to cut grass, as a lawn mower (Dictionary.com). Thus, Automatic Grass Cutter (AGC) can be defined as systems that self activates or is executed under programmed or specified conditions and performs specified functions in grass cutting.


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This Automatic Grass Cutter robot is categorized as domestic robot. Domestic robots for vacuuming and lawn mowing are mobile units that use autonomous mobile robotics technology. Outdoor robots, such as those for lawn mowing, are designed to avoid rollover and collision incidents (Sahin and Guvenc, 2007). A mobile robot is one which can move around its environment independently. In order to do this the robot needs to be able to navigate, and the range and accuracy of navigational ability required will vary depending on the size of the robot and the type of task it carries out. Types of mobile robot currently in production include the domestic robot, which comes in a variety of forms ranging from the robot vacuum cleaner to the robot dog. Potential future uses of the mobile robot include robot paramedics, farmhands and border guards (wiseGEEK.com). Figure 1.1 shows the domestic robots under the service-robot category assist humans in performing everyday chores. This task-based classification of robots shows the location of domestic robots in the robot family tree.

Figure 1.1: Robot types (Sahin and Guvenc, 2007) Robots

Industrial

Robots Service Robots

Medical Purpose Robots Construction Robots Robots for Hazardous Environment s Entertainment Robots Domestic Robots


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1.1 Problem Statement

Generally, in Malaysia, there is no Automatic Grass Cutter technology yet by using mobile robot. By using Automatic Grass Cutter, robots technology can replace or ease the role of human. Robots are able to perform repetitive tasks more quickly and accurately than humans. In order to cut grass with path planning and in specific perimeter (2.5M (L) x1.5M (W)) and to make sure it will perform the task by Automatic Grass Cutter (AGC), this robot will be designed and analyzed to make sure it will perform the task as Automatic Grass Cutter in lawn mowing. This specific perimeter is chosen because to make as testing parameter of AGC. The robots should know the area that it will perform the tasks. This robot also can estimate their starting position to move to the end position. Besides that, the robot will operate in day where there is plenty of sunlight by using solar panel. This robot cannot operate in rainy day. These AGC operate in simple movement, with a predetermined environment. If any obstacle exists in front of its way, it can avoid and continue it tasks by moving in another direction to achieve its goals.

1.2 Objectives

Objectives for this project that need to be achieved:-

i) To design a small and portable automatic grass cutter that can perform their tasks efficiently while avoiding the obstacle.

ii) To analyze the selected design by using cutting speed, feed rate and machining time formula.


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1.3 Scope

Project scopes are important in order to design this project, and it is required to analyze the project. The scopes will cover design and programming of a mobile robot. Part of design will include the application of drawing software such as electric and electronic part are related in programming where are needed to develop the interface between programming, electronic circuit and mechanical system. The scopes of this project

are:-i. The system of Automatic Grass Cutter is control by using PIC microcontroller and the simulation of selected design.

ii. It will perform the tasks only in lawn area of perimeter (2.5M (L) x1.5M (W)).


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CHAPTER 2

LITERATURE REVIEW

This chapter will present the literature reviews relevant to this project. It will show the overview in autonomous mobile robotic, the application of mobile robotic, the service robot and the domestic robot. Moreover, it includes PIC microcontroller programming, interfacing of sensors and actuator, obstacle avoidance mechanism, path planning, sensor, and algorithm concept that will be stated after.

2.1 Autonomous Mobile Robotics and Their Applications

Due to rapid development in the present information and communication systems, robots are designed to be widely used in small and large scale in every area of daily life and industries. They are employed to reduce human dependencies in performing a task and to reduce time for production while maintaining consistent quality of production outputs. Mobile robots are widely used in manufacturing industries, advance surveillance systems and for domestic use as well. Mobile robot is divided in two types. First, the industrial robots and second, is service robots. A service robot is a robot that is capable of providing services to its owner. These robots generally are autonomous but can be controlled, either remotely or manually, by built-in systems. They also might be synced up with Wi-Fi home networks or smart environments (wiseGEEK.com). Service robots can differ in specific functions, but their jobs usually can be described as helping humans perform tasks that are dangerous, difficult, dirty, repetitive or distant. A service robot can ease the workload of a human being in this way, especially if the task is frequent, such as


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with home chores. Moreover, service robots also can be used in domestic robot, entertainment robots, robots for hazardous environments, construction robots and medical purpose robots. Service robots are particularly useful in the automotive industry, where heavy lifting and fine calibrations are required to build a vehicle.

Example for service robot application is in hospital, Automated Guided Vehicles (AGV), security and outdoor. Figure 2.1 shows the TransCar AGV. This TransCar AGV is the ideal healthcare industry automated guided vehicle. This AGV moves routine and on-demand deliveries of medical supplies (Swisslog.com). TransCar automated guided vehicles travel across multiple-floor facilities with narrow aisle-ways and human traffic, and relieves hospital staff of heavy lifting tasks. This AGV system does not require embedded wire, tape, or chemically applied guide paths.

Figure 2.1: TransCar AGV (Swisslog.com).

Meanwhile, the other application in AGV is for industry and retail applications. Figure 2.2 shows the AGV systems for industry and distribution. These automated guided vehicle systems have flexible and advanced navigation systems, and interface with elevators, doors and lifters. These AGV system link storage and production with light payloads to full pallet transport (Swisslog.com).


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Figure 2.2: AGV systems for industry and distribution (Swisslog.com).

On the other hands, domestic robots also are service robots. Domestic robots are widely popular. A service robot used around the home can do anything from vacuum a carpet to mow a lawn. A domestic robot can help its owner clean pools, mop floors and iron clothes. Some robots can even help homeowners clean up after pets. In cases like these, a robot can routinely pick up fur that has been shed or it can clean litter boxes after cats have used them, ensuring that the litter boxes remain fresh and that odors are controlled.

The example of application in domestic robots is lawn wowing. For example, modern houses include a compound often used as garden with grass which grows and need to be maintained at a short height. Conventional lawn mowing is often a hassle and time consuming in cutting the grass. The task of manual lawn mowing can be replaced by automatic lawn mower using a robot programmed to perform such task (Baloch and Timothy, 2008). Figure 2.3 shows this Robomower from FriendlyRobotics. The Robomower uses V-shaped patterns for mowing. When the Robomower detects an obstacle, it stops and turns.


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Another example of domestic robots is Automower from Husqvarna as shown in Figure 2.4. Hobbyists use autonomous lawn mowers like the Automower as an inexpensive platform for building mobile robots.

Figure 2.4: Automower from Husqvarna (Sahin and Guvenc, 2007).

Domestic robots for vacuuming and lawn mowing are mobile units that use autonomous mobile robotics technology. Moreover, vacuum robot also under the domestic robot. Figure 2.5 shows the Trilobite from Electrolux. This device returns to the charging station, charges itself, and continues vacuuming. While the Figure 2.6 shows Trilobite from Electrolux in action. The Trilobite establishes a map of the room as it vacuums. Magnetic strips are needed to mark stairs and doors.

Outdoor robots, such as those for lawn mowing, are designed to avoid rollover and collision incidents. Indoor robots, such as those for vacuuming, have less demanding environmental conditions but still face obstacles. Obstacle-avoidance technology is thus applicable to both cleaning and lawn-mowing robots.


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Figure 2.5: Trilobite from Electrolux (Sahin and Guvenc, 2007).

Figure 2.6: Trilobite from Electrolux in action (Sahin and Guvenc, 2007).

Real-time control of autonomous vehicles is designed using embedded systems architecture. A field bus is used for communication between sensors, controllers, and navigation system modules (Sahin and Guvenc, 2007).

Robots are often expensive and costly which often discourages people from buying costly robotic devices. The success of manufacturing a low cost inexpensive for example an automatic lawn mower will allow house owners to maintain their lawn without spending much time and money because an autonomous robot can mow the lawn of a given specific area of the garden without any human supervision.


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4 1.3 Scope

Project scopes are important in order to design this project, and it is required to analyze the project. The scopes will cover design and programming of a mobile robot. Part of design will include the application of drawing software such as electric and electronic part are related in programming where are needed to develop the interface between programming, electronic circuit and mechanical system. The scopes of this project

are:-i. The system of Automatic Grass Cutter is control by using PIC microcontroller and the simulation of selected design.

ii. It will perform the tasks only in lawn area of perimeter (2.5M (L) x1.5M (W)).


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CHAPTER 2

LITERATURE REVIEW

This chapter will present the literature reviews relevant to this project. It will show the overview in autonomous mobile robotic, the application of mobile robotic, the service robot and the domestic robot. Moreover, it includes PIC microcontroller programming, interfacing of sensors and actuator, obstacle avoidance mechanism, path planning, sensor, and algorithm concept that will be stated after.

2.1 Autonomous Mobile Robotics and Their Applications

Due to rapid development in the present information and communication systems, robots are designed to be widely used in small and large scale in every area of daily life and industries. They are employed to reduce human dependencies in performing a task and to reduce time for production while maintaining consistent quality of production outputs. Mobile robots are widely used in manufacturing industries, advance surveillance systems and for domestic use as well. Mobile robot is divided in two types. First, the industrial robots and second, is service robots. A service robot is a robot that is capable of providing services to its owner. These robots generally are autonomous but can be controlled, either remotely or manually, by built-in systems. They also might be synced up with Wi-Fi home networks or smart environments (wiseGEEK.com). Service robots can differ in specific functions, but their jobs usually can be described as helping humans perform tasks that are dangerous, difficult, dirty, repetitive or distant. A service robot can ease the workload of a human being in this way, especially if the task is frequent, such as


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with home chores. Moreover, service robots also can be used in domestic robot, entertainment robots, robots for hazardous environments, construction robots and medical purpose robots. Service robots are particularly useful in the automotive industry, where heavy lifting and fine calibrations are required to build a vehicle.

Example for service robot application is in hospital, Automated Guided Vehicles (AGV), security and outdoor. Figure 2.1 shows the TransCar AGV. This TransCar AGV is the ideal healthcare industry automated guided vehicle. This AGV moves routine and on-demand deliveries of medical supplies (Swisslog.com). TransCar automated guided vehicles travel across multiple-floor facilities with narrow aisle-ways and human traffic, and relieves hospital staff of heavy lifting tasks. This AGV system does not require embedded wire, tape, or chemically applied guide paths.

Figure 2.1: TransCar AGV (Swisslog.com).

Meanwhile, the other application in AGV is for industry and retail applications. Figure 2.2 shows the AGV systems for industry and distribution. These automated guided vehicle systems have flexible and advanced navigation systems, and interface with elevators, doors and lifters. These AGV system link storage and production with light payloads to full pallet transport (Swisslog.com).


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Figure 2.2: AGV systems for industry and distribution (Swisslog.com).

On the other hands, domestic robots also are service robots. Domestic robots are widely popular. A service robot used around the home can do anything from vacuum a carpet to mow a lawn. A domestic robot can help its owner clean pools, mop floors and iron clothes. Some robots can even help homeowners clean up after pets. In cases like these, a robot can routinely pick up fur that has been shed or it can clean litter boxes after cats have used them, ensuring that the litter boxes remain fresh and that odors are controlled.

The example of application in domestic robots is lawn wowing. For example, modern houses include a compound often used as garden with grass which grows and need to be maintained at a short height. Conventional lawn mowing is often a hassle and time consuming in cutting the grass. The task of manual lawn mowing can be replaced by automatic lawn mower using a robot programmed to perform such task (Baloch and Timothy, 2008). Figure 2.3 shows this Robomower from FriendlyRobotics. The Robomower uses V-shaped patterns for mowing. When the Robomower detects an obstacle, it stops and turns.


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Another example of domestic robots is Automower from Husqvarna as shown in Figure 2.4. Hobbyists use autonomous lawn mowers like the Automower as an inexpensive platform for building mobile robots.

Figure 2.4: Automower from Husqvarna (Sahin and Guvenc, 2007).

Domestic robots for vacuuming and lawn mowing are mobile units that use autonomous mobile robotics technology. Moreover, vacuum robot also under the domestic robot. Figure 2.5 shows the Trilobite from Electrolux. This device returns to the charging station, charges itself, and continues vacuuming. While the Figure 2.6 shows Trilobite from Electrolux in action. The Trilobite establishes a map of the room as it vacuums. Magnetic strips are needed to mark stairs and doors.

Outdoor robots, such as those for lawn mowing, are designed to avoid rollover and collision incidents. Indoor robots, such as those for vacuuming, have less demanding environmental conditions but still face obstacles. Obstacle-avoidance technology is thus applicable to both cleaning and lawn-mowing robots.


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Figure 2.5: Trilobite from Electrolux (Sahin and Guvenc, 2007).

Figure 2.6: Trilobite from Electrolux in action (Sahin and Guvenc, 2007).

Real-time control of autonomous vehicles is designed using embedded systems architecture. A field bus is used for communication between sensors, controllers, and navigation system modules (Sahin and Guvenc, 2007).

Robots are often expensive and costly which often discourages people from buying costly robotic devices. The success of manufacturing a low cost inexpensive for example an automatic lawn mower will allow house owners to maintain their lawn without spending much time and money because an autonomous robot can mow the lawn of a given specific area of the garden without any human supervision.