DESIGN AND FABRICATE BRAKING SYSTEM FOR THE ELECTRIC BUGGY CAR

MUHAMMAD BIN ZULKIFLY

A report submitted in partial fulfillment of the

requirements for the award of the degree of

Bachelor of Mechanical Engineering

Faculty of Mechanical Engineering

Universiti Malaysia Pahang

NOVEMBER 2007

ABSTRACT

Nowadays, brake system is probably the most important system for vehicle.

Most buggy cars have disc brakes on the rear wheels, and some have disc brakes on

all four wheels. This is the part of the brake system that does the actual work of

stopping the car. The main thing in the braking system is caliper, master cylinder,

disc brake or rotor and the hose or piping. Research and comparison are done to

make sure the flow of the project run smoothly. To design the suitable breaking

system for Electric Buggy Car must depend on the speed the vehicle, maximum

weight of baggage and weight driver and body. From the research that we get from

the design before, for suitable these Electric Buggy Car breaking system to use is

motorcycle RXZ/TZM breaking systems or Go Kart breaking system. The

Motorcycle and Go Kart breaking system is simple and efficient for the Electric

Buggy Car and easy to maintenance the brake and not complicated system. In this

Electric Buggy Car we selected to use the motorcycle Yamaha 125Z Braking system

because of the low cost of the part compared with the Go Kart Braking System. The

most of the problem in this project is selected of the push rod because of the material

cannot withstand the high force when the brake is applied. To overcome the trouble,

modification and testing is the process of the recovered. Finally, the Braking System

for the Electric Buggy Car can functionally with the best performance.

A

ABSTRAK

Pada masa sekarang, perkembangan dunia automotif adalah semakin

berkembang pesat. Sebagai contoh dalam pembinaan rekabentuk Buggy Car itu

sendiri kebanyakkannya telahpun mula menggunakan system brake disc terutama

sekali diletakkan di bahagian belakang kenderaan tersebut dan ada juga mempunyai

system brake disc di kedua-dua belah bahagian depan dan belakang kereta tersebut.

Fungsi utama kegunaan system brake itu sendiri tentunya adalah untuk

memberhentikan kenderaan itu sendiri. Komponen utama dalam pembentukan

system brake itu mestilah mempunyai Caliper Brake, Master Cylinder, Disc Brake

atau Rotor, system piping atau hose dan juga pedal. Didalam pembinaan system

brake bagi kenderaan mi adalah semestinya bergantung kepada kelajuan maksima

yang boleh dicapai oleh kenderaan tersebut, berat maksima kenderaan tersebut

bersama-sama pemandu dan penumpang serta berat maksima muatan yang boleh

ditampung dan dibawa. Daripada kajian yang telah dijalankan, system brake yang

bersesuaian bagi kenderaan Buggy Car mi adalah menggunakan system brake

daripada Yamaha 125Z. Sistem braking motosikal adalah yang terbaik , mudah dan

senang dalam melakukan kerja penyelenggaraan , efficient dan system brake tersebut

adalah tidak terlalu rumit untuk di rekabentuk kepada keadaan rekabentuk Buggy Car

tersebut. Selain daripada iii, juga,dari segi aspek kos dalam mendapatkan spare part

untuk braking sistem juga adalah rendah dan mudah didapati jika di bandingkan

dengan braking sistem yang lain. Dalam pembinaan projek mi masalah utama yang

telah dihadapi adalah bar ataupun palang untuic menekan atau mengepam master cylinder yang path awal penggunaannya adalah tidak tahan kepada daya yang tinggi

apabila pedal ditekan. Dalam mengatasi masalah ini,pengubahsuain pada bar

ataupun palang sering dibuat mengikut ketahanan dan kesesujan supaya masalah

dapat diatasi. Pada akhirnya, keberkesanan dan fungsi system brake tersebut telah

dapat mencapai tahap keberkesanannya.

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TABLE OF CONTENTS

CHAPTER

TITLE

PAGE

ACKNOWLEDGEMENT VI ABSTRACT VII ABSTRAK VIII LIST OF FIGURES XII LIST OF TABLES XV LIST OF CHART XVI

INTRODUCTION

1.1 Project background

1.2 Objectives

1.3 Scopes of project

2 LITERATURE REVIEW

2.1 History of Disc Brake

2.2 Introduction of Disc Brake

2.3 Basic Brake System

2.4 The Operation of The System

2.5 Hydraulic Principle

2.5.1 Liquid will not compress

2.5.2 Air will compress

2.5.3 Force and Pressure

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2

2

3

5

6

7

8

9

9

10

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3

2.6 Basic principle of a hydraulic brake system 11

2.7 Master Cylinder 12 2.7.1 The Operation of Master Cylinder 12

2.8 Caliper 13

2.8.1 Fixed Caliper 14

2.8.2 Floating Calipers 14 2.9 Brake Disc 15

2.9.1 Features of disc brake 16 2.10 Disc Pads 17 2.11 Tubing and Hose 18 2.12 Brake Fluid 21 2.13 Brake Lining 22 2.14 Gas Metal Arc Weld 24 2.15 Product Development Process 26 2.16 Product Development Process for Proposed

Braking System for Electric Buggy Car 27 2.17 Requirement Definition 27 2.18 Conceptual Design 28 2.19 Detail Design 28 2.20 Test and Evaluation 29 2.21 Manufacturing 30 2.22 Logistic, Supply Chain and Environment 30

METHODOLOGY

3.1 Introduction 32 3.2 The Methodology 33 3.3 Literature review 33 3.4 Proposed design 34

3.4.1 Preliminary design 34

3.4.2 Detail design 34 3.5 Fabrication 35 3.6 Test run 38 3.7 Result and Analysis 39

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3.8 Final Report 39

3.9 Flow Chart 40

4- RESULT AND DISCUSSION

4.1 Overview 41 4.2 Finish Product 42

4.2.1 Result 42 4.3 Observation and Analysis 43 4.4 Brake Analysis 44

4.4.1 Drive Ratio 44 4.4.2 Strength of the material 45 4.4.3 Maximum heat dissipation of brake 46

4.4.4 Minimum Braking Time and Distance 47 4.5 Problem and Solution 49

CONCLUSION

5.1 Conclusion 50 5.2 Recommendation 51

5.2.1 Disc Plate 51

5.2.2 Push Rod 52 5.2.3 Caliper Situate 52

REFERENCE

APPENDIX 54

LIST OF FIGURE

FIGURE NO. TITLE PAGE

2.1 Basic operation of breaking system 7

2.2 Fluid transmit pressure equally throughout a hydraulic

Circuit and act with an equal force on each surface of the

same size 8

2.3 Force applied to a liquid transmit the pressure 9

2.4 Force applied to the piston compressed the air not liquid 10

2.5 Force transmitted by hydraulic means from one cylinder 10

to another

2.6 Basic principle of a hydraulic brake system 11 2.7 Basic master cylinder 13

2.8 Fixed Calipers 14 2.9 Floating Caliper 15 2.10 Dics brake 17 2.11 Section of a disc and caliper showing the cylinder, pistons 17

and pad

2.12 Disc brake pads 17 2.13 Flexible rubber hose 18 2.14 Hydraulic hose and tubing 19 2.15 Quality brake tubing is made by a wrapping a strip of steel 19 2.16 The most common cause of hose failure are shown above 20 2.17 Shows the dry and wet boiling point for several brake fluid 22 2.18 Brake Lining 23 2.19 Basic equipment in GMAW operations 25 2.20 GMAW Process . 26 3.1 Final Design of Bubby Car and Assembly with Braking System 35 3.2 Frame Works 36

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3.3 Caliper Braking System assembly 36 3.4 Pedal assembly with Frame 37 3.5 Master Cylinder connected with push rod and the state of

Hydraulic trace oil 37 3.6 Pedal connected with push rod and the stopper 38 3.7 Project Flow chart 40 4.1 Part of the Braking System to the frame 42 4.2 ETEK Motor D.0 43

Appendix A Complete Fabrication Process

5.1 Isometric view Buggy Car and Braking Assembly 54 5.2 Side view and braking assembly with pedal, push rod, hose,

Master cylinder, plate disc and caliper 54 5.3 Back View Caliper and plate disc with hose 55

5.4 Side View and Caliper with Brake disc 55

Appendix B- Technical Drawing

5.5 Isometric View from Solid work 56 5.6 Top View from Solid work 56 5.7 Back View from Solid work 57 5.8 Side view from Solid work 57 5.9 Front View from Solid work 58 5.10 Master Cylinder drawing 59 5.11 Brake Disc drawing 59 5.12 Connector drawing 60 5.13 Brake Fluid Trace drawing 60 5.14 Hose drawing 61 5.15 Brake Pedal drawing 61 5.16 Caliper Brake Disc drawing 62

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Appendix C Detail Drawing

5.17 Buggy Car Assembly 63 5.18 Frame Structure 64 5.19 Pedal Brake detail drawing 65 5.20 Push Rod detail drawing 66 5.21 Hose detail drawing 67 5.22 Brake Disc detail drawing 68 5.23 Brake Fluid Trace detail drawing 69 5.24 Master Cylinder detail drawing 70 5.25 Connector detail drawing 71 5.26 Caliper Brake disc detail drawing 72

LIST OF TABLE

TABLE TITLE PAGE

2.1 The dry and wet boiling point requirement of DOT 3,4 21 and 5 brake fluid

2.2 Shows the operating characteristic for the three organic 23

and four metallic lining types

2.3 Some of the advantages and disadvantage of different 24 lining type

5.1 Gantt Chart for PSM 1 73

5.2 Gantt Chart for PSM 2 74

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CHAPTER 1

INTRODUCTION

1.0 Project Background

Nowadays Electric Buggy Car at airport is popular around the world using for

carry all the passenger baggage. People use the buggy car is using for caring

something that the people can handle or bring uses their hand.

The brake system is probably the most important system for vehicle. Most

buggy cars have disc brakes on the rear wheels, and some have disc brakes on all

four wheels. This is the part of the brake system that does the actual work of

stopping the car.

There are two design of break disc is solid disc and ventilated disc. Brake

disc make from cast iron, with a ground surface on each side against which the pads

are applied. The disc is shaped to fit over the wheel hub and has a drilled hole to fit

the wheel studs. To design the suitable breaking system for Electric Buggy Car must

depend on the speed the vehicle, maximum weight of baggage and weight driver and body.

For suitable these Electric Buggy Car breaking system to use is motorcycle

RXZ/TZM breaking systems or Go Kart breaking system. The motorcycle and Go

Kart breaking system is simple and efficient for the Electric Buggy Car and easy to maintenance the break and not complicated system. The break disc system use

hydraulic oil to transmit force and also increase the force. The breaking system

PA

operated with fluid (oil). Hydraulics is part of the more general discipline of fluid

power to function the breaking system.

1.2 Project Objective

To design the breaking system for Electric Buggy Car

To fabricate the breaking system

1.3 Scopes Of Project

• Research on Hydraulic Break Disc System conducted to collect

information as required in literature review.

• Use motorcycle breaking system (YAMAHA 125Z) or Go Kart

Breaking System to appropriate for the design of Buggy Car.

• Analyze the efficiency / function the Breaking System from the ETEK

motor 24-48 Volt D.C.

• Develop the suitable breaking system for Buggy Car using motorcycle

or go kart braking system.

• Design and fabricate the breaking system from pedal to break disc

depend on the frame structure.

• Low cost for the design of the Braking System.

CHAPTER 2

LITERATURE REVIEW

2.1 HISTORY OF DISC BRAKE

As the level of technology of transportation has increased, the mechanical

devices used to slow down and stop vehicles has also become more complex. The

history of vehicular braking technology and possible future developments.

Before there was a "horse-less carriage," wagons, and other animal drawn

vehicles relied on the animal's power to both accelerate and decelerate the vehicle.

Eventually there was the development of supplemental braking systems consisting of

a hand lever to push a wooden friction pad directly against the metal tread of the

wheels. In wet conditions these crude brakes would lose any effectiveness.

In this chaotic era is the first record of the disk brake. Dr. F.W. Lanchester

patented a design for a disk brake in 1902 in England. It was incorporated into the

Lanchester car produced between 1906 through 1914. These early disk brakes were

not as effective at stopping as the contemporary drum brakes of that time and were

soon forgotten. Another important development occurred in the 1920's when drum

brakes were used at all four wheels instead of a single brake to halt only the back

axle and wheels such as on the Ford model T. The disk brake was again utilized

during World War II in the landing gear of aircraft. The aircraft disk brake system

was adapted for use in automotive applications, first in racing in 1952, then in

production automobiles in 1956. United States auto manufacturers did not start to

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incorporate disk brakes in lower priced non-high-performance cars until the late

1960's.

Early disk brake systems required an outside mechanical brake booster such

as a vacuum assist or hydraulic pump to generate the pressure for primitive friction

materials to apply the necessary braking force.

A recent Ducati concept show bike uses brake disks of silesium, developed

by the Russian aerospace industry(3), which claim to have the friction coefficient of

cast iron with the light weight of carbon fiber.

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2.2 Introduction of Breaking System

The breaking system provides the means to stop or slow the vehicle. To

control for the vehicle, we need to be able to start it moving, make it turn, accelerate

and decelerate and of the major importance to stop it. A vehicle with a breaking

system that is not working properly is a candidate for the wreaking yard and may be

cause injury to the driver and passenger as well as to others.

The breaking system is considered by many people to be the most important

system involved in the operation of the vehicle. We do not normally use brakes at

their maximum capability, but we want the system to work flawlessly in emergency

much like parachute. Most of user find hard breaking unpleasant and avoid hard

stops. The breaking system of most vehicle are rarely tested ensure that they are

working at minimum efficiency.

The ideal breaking system is one of that will allow the driver to bring a

vehicle to a stop in the shortest possible distance. To be able to do this, it should

have an enough power to lock up and skid all tires while stopping on clean, dry

pavement. Also, stopping should occur with a moderate amount of pedal pressure so

that even weaker drivers can achieve tire lockup.

No legislation specifies exactly what to do, and there are no commonly used

test devices or instruments to access exactly how good or bad a brake system is.

2.3 Basic Brake System

The parts are as follow:-

1. Brake Pedal - Operated by the driver.

2. Brake booster - Provides the brake easier to apply

3. Master cylinder - Provides hydraulic pressure

4. Caliper and Disc - Slow or stop the wheels when the brake calipers at

the wheel.

5. Brake lines and Hoses - Connect the master cylinder to the caliper at the

wheels

6. Brake Fluid - Transmits force from the master cylinder to the

calipers at the wheels.

7. Connector Rod - Connected from brake pedal until master cylinder to

transmit the pressure when pedal is apply.

caliper

caliper

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2.4 The Basic Operation of the System

When the driver pushes the brake pedal fro the figure 2. 1, force will be

transmitted to the piston in the master cylinder. The pistons will apply the pressure

to the fluid in the cylinder and the brake lines transfer the pressure to the caliper.

The pistons in the hydraulic cylinder in the caliper are move to apply the brakes.

When disc brake is applied, brake pad is clamped against the disc. A moving

vehicle has energy, which must be absorbed by the brakes when they are applied.

The energy is converted into heat as a result of the friction between the breaking

surfaces. The heat is then dissipated into the brake parts and into the surrounding

atmosphere. Therefore, the brake pad and disc or the brake lining, the material must

be withstood high temperature as well as high pressure.

Figure 2.1 Basic operation of breaking system

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2.5 Hydraulic Principle

The hydraulic system (Fluid Power) is a method of transmitting the motion or

force. It does this by having a cylinder and piston in a different sizes. Hydraulic is

based on the fact that liquid can flow easily through complicated path, yet cannot be

compressed. Another important feature is that when liquid transmit pressure, that

pressure will be transmitted equally in all direction. This is known as Pascal's

Principle. The figure 2.2 had shown the basic of Pascal's Principle.

Figure 2.2 Fluid transmit pressure equally throughout a hydraulic circuit and act with an equal force on each surface of the same size.

2.5.1 Liquid will not compress

For all practical purpose, liquids are not compressible and so hydraulic

pressure represents a pressure applied to the liquid. It does not mean that the liquid

is reduced in volume, as is the case with a gas. Refer to cylinder in figure 2.3 which

contains liquid and a piston. As a result of the force on the piston, the liquid applies

pressure to the walls and the bottom of the cylinder. From the figure 2.3 the piston

does not move because there is nowhere for the liquid to go.

Figure 2.3 Force applied to a liquid transmit the pressure

2.5.2 Air will compress

If the cylinder contains both air and liquid, a force applied to the piston will

compress the air and reduced its volume and the piston will move down the cylinder

(Figure 2.4). When the force is removed, the piston will return to its original position.

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Figure 2.4 Force applied to the piston compressed the air not liquid

2.5.3 Force and Pressure

Figure 2.5 shows the 2 cylinder of the same size (diameter). Forced applied

to one piston is being transfer hydraulically to the other. Because the cylinder and

the piston are the same size, the force applied to one piston will be the same as the

forced delivered by the other. However, by having cylinders of different size, force

can be increased or reduced.

Figure 2.5 Force transmitted by hydraulic means from one cylinder to another.

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2.6 Basic principle of a hydraulic brake system

Figure 2.6 is a simple hydraulic brake system with three cylinders of different

size. The diagram can be used to explain force and pressure.

0

When the pedal is pressed, the force against the piston in the master cylinder

(A) will apply pressure to the fluid. The pressure will be the same in all part of the

system, but will have a different effect on the piston in the other cylinder. There will

be different forces from the piston as follows:

1. Cylinder (B) is smaller than (A), so the force from (B) will be less than the

force applied to (A).

2. Cylinder (C) is larger than (A), so the force from its piston will be greater

than the force applied to (A).

In an actual hydraulic brake system, the master cylinder is smaller than the

wheel cylinder, so the force all the wheel cylinder is increased. The force can be

varied by the use of different sized cylinder and it can be varied from front to rear to

provide better breaking. This can be done even though the pressure is same in all part of the System.

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2.7 Master Cylinder

The figure 2.7 is shown the basic operational of master cylinder. The master

cylinder is the input piston for the vehicle break system. It is connected to the break

pedal so the movement of the break pedal is transmitted to the master cylinder piston

by a pushrod. The first master cylinder used a single piston and cylinder bore with

one outlet at the end of the bore. From this outlet, tubing branched out to each of the

wheel cylinder.

The master cylinder body has two major areas, the piston and the cylinder

bore and the reservoir. These two areas are connected by two passages, a small

compensating port and a larger bypass port (intake or replenishing port).

2.7.1 The Operation of Master Cylinder

1. When the break applied, the primary piston is moved in its bore and fluid is

displaced by the piston.

2. Because of its larger bore, there will be more fluid displaced by the rear part of

the primary piston than by the front.

3. This is can be produced a high volume of fluid, which quickly moves the brake

Pad to take up the clearance between them and the disc.

4. With continued movement of the piston, pressure builds up in the system ahead

of the piston to apply the breaks.

5. This is also some pressure created in the large bore behind of the head of piston.

This pressure opens the ball in the fast fill valve so that fluid can flow from the

large bore back into the reservoir.

6. Once the fast fill valve has opened, the cylinder acts in the same way as a conventional master cylinder, with all the pressure being created in the small bore

section of the master cylinder.

compensating port

13

return Spring

check valve

inlet port I

Figure 2.7 Basic master cylinders

2.8 Caliper

The two major style of caliper are used on vehicle:-

1. Fixed Caliper

2. Floating Caliper

Most caliper use a cup shaped bore in a cast iron caliper body. Each bore will

include a piston with a seal and boot, and a bleeder screw. A few pistons include an

insulator to block heat flow from the lining to the piston. Disc brake experienced

higher brake fluid operating temperature because the fluid in the caliper body is

fairly close to the friction material, and the caliper body and piston conduct quite a bit of heat to the fluid.

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2.8.1 Faxed Caliper

A fixed caliper assembly and a solid disc are illustrated in figure 2.8. Two

piece calipers are used, with two parts being bolted together. The caliper has two

cylinders, one on each side of the disc, and so each piston operates its own brake pad.

When the brakes applied, hydraulic pressure is applied to the piston and the piston

and they move the pads against the disc equal force.

Figure 2.8 Fixed Calipers

2.8.2 Floating Calipers.

The dismantled part of the floating caliper assembly is shown in figure 2.9.

The main parts of the assembly are the caliper housing, the anchor plate, the piston

and the pads. This type of the caliper is made as single part and has only one

cylinder, which is built into the inner side of caliper.