Design and validate passive automotive engine mount system.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

Design and Validate Passive Automotive Engine Mount System

This report submitted in accordance with requirement of the Universiti Teknikal Malaysia Melaka (UTeM) for the Bachelor Degree of Engineering Technology

(Automotive Technology) (Hons.)

AHMAD AIZAT AQMAL BIN HISHAMUDDIN B071110372

891208 – 13 – 5847

FACULTY OF ENGINEERING TECHNOLOGY 2015

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TAJUK: Design and Validate Passive Automotive Engine Mount System

SESI PENGAJIAN: 2014 / 2015 Semester 2

Saya AHMAD AIZAT AQMAL BIN HISHAMUDDIN

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 sebagaimana yang termaktub dalam AKTA RAHSIA RASMI 1972)

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

Alamat Tetap:

NO.116 LOT4327 LRG DESA ILMU 22A2 PH 15 TMN DESA ILMU 94300 KOTA SAMARAHAN, SARAWAK.

Tarikh: ________________________

Disahkan oleh:

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS LAPORAN PROJEK SARJANA MUDA

Cop Rasmi:

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DECLARATION

I hereby, declared this report entitled “Design and Validate Automotive Passive Engine Mount Engine” is the results of my own research except as cited in

references.

Signature :

Author’s Name : AHMAD AIZAT AQMAL BIN HISHAMUDDIN

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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 degree of Bachelor of Engineering Technology (Automotive Technology) (Hons.). The member of the supervisory is as follow:

……… (Project Supervisor)

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ABSTRAK

Pada zaman pasca kini, kebanyakkan kenderaan baru mempunyai penyerap gegaran pada bahagian enjin sesebuah kenderaan berbanding dengan kenderaan terdahulu. Sistem penyerap gegaran kini lebih peka terhadap setiap gegaran yang terhasil dan akan lebih menjamin keselesaan pemandu dan penumpang. Satu kaedah telah diketengahkan untuk menyerap gegaran dengan menghasilkan isolator gegaran yang berkos rendah yang boleh digunakan pada sistem penyerap gegaran untuk mengurangkan kadar gegaran. Berdasarkan pengajian ini, pendekatan yang positif dengan cara mengurang kadar penglibatan kos rendah adalah dengan menambah sistem penyerap gegaran daripada satu kepada empat sistem penyerap gegaran enjin. Aplikasi akan digunakan pada “test rig” bersertakan dengan enjin yang mempunyai beban yang tidak seimbang akan dikenakan pada enjin tersebut. Hasil kajian yang berterusan akan dilaksanakan bagi menyediakan asas dinamik kebebasan yang juga dikenali sebagai “degree of freedom” pada sistem penyerap gegaran enjin, model pasif simulasi sistem penyerap gegaran hidraulik, dan reka bentuk terperinci pada model kenderaan, dan pebinaan “test rig” untuk menjalankan eksperimen.

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ABSTRACT

Now-a-days the demand for low cost, quiet operation, and increased operator comfort in automobiles and other applications is requiring that new techniques be developed for noise and vibration isolation. One approach to reduce noise and vibration harshness is to develop low cost vibration isolator that can be used to mount components that generate vibration. To develop this isolator, the passive engine mounting were studied. Based on this study, the most promising approach is by adding four mounts of the engine mounting instead of one engine mounted on the test rig to decrease the vibrations, noise and harshness. This application will be applied on test rig and with unbalanced load engine. The progress results that this study provides are; a fundamental dynamic Degree of Freedom (DOF) equation of the passive engine mount system, a simulation model of a passive hydraulic engine mount, a detail design of a model the passive engine mounts, and fabricate a test rig to run experiments.

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DEDICATION

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ACKNOWLEDGEMENT

First and Foremost, I would like to express my greatest appreciation and thanks to Universiti Teknikal Malaysia Melaka for giving me the opportunity to undergo my final year “Projek Sarjana Muda” under the supervision of ENGR. Mr. Muhamad Hafiz Bin Harun. A special thank you also goes to my supervisor ENGR. Mr. Muhamad Hafiz Bin Harun and my co-supervisor Mr. Fauzi Bin Ahmad for his dedication and guidance during the period of undergoing my project and also to master student Mohamad Zaharudin Bin Sariman for his guidance.

Last but not least, I want to thank my beloved mother and beloved father and Haji

Ariffin’s whole family members for their encouragement and support as well as to all

my friends Nik Isna Zulkarnain Bin Nik Iskandar Ariff, Muhd Amirul Zulhilmi Bin Mohd Saru, Muhamad Afnan Bin Haji Mohd Aris, Muhammad Norsyafiq Bin Md Nasib, and Mohamad Shahrul Amierul Bin Ramli who never give up encouraging me to complete this report.

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TABLE OF CONTENT

Declaration Approval Abstrak Abstract Dedication Acknowledgement Table of Content List of Tables List of Figures

List Abbreviations, Symbols and Nomenclatures

i ii iii iv v vi vii viii ix x

CHAPTER 1: INTRODUCTION 1

1.1 Background 2

1.2 Project Problem Statement 2

1.3 Project Objective 2

1.4 Scope of Project 2

1.5 Approach 2

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CHAPTER 2: LITERATURE REVIEW 3

2.1 Introduction 3

2.2 Types of Engine Mount 4

2.2.1 Passive Hydraulic Engine Mount 6

2.2.1.1 The Adaptive Hydraulic Mount 9 2.2.1.1.1 Property Characterization of

Hydraulic Mount 12

2.2.1.1.2 Characterization of Hydraulic

Mount Properties 12

2.2.1.2 Elastomeric Mount 13

2.2.1.3 Hydraulic (fluid) Mount 16

2.2.2 Active Engine Mounting 20

2.2.3 Semi-Active Engine Mounting 24

2.2.3.1 Magnetorheological Fluid – Elastomers 27

2.3 Operation of Engine Mounting 28

2.3.1 Dependency of Location of the Notch

And Peak Frequencies on the Mount Parameters 32 2.3.2 Dependency of Location of the Notch

And Peak Height to Damping 32

2.4 Engine Mounting Test Rig 33

2.5 Accelerometer Sensor 35

2.5.1 Principles of Operation 35

2.5.2 Types of Accelerometer 36

2.6 Mathematical Equation 37

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CHAPTER 3: METHODOLOGY 40

3.1 Introduction 40

3.2 Flow Chart 42

3.3 Passive Engine Mounting System – 3DOF 43

3.4 MATLAB Simulink 46

3.5 Develop Engine Mount Test Rig 50

3.6 Proposed Experimental Setup 51

CHAPTER 4: RESULT AND DISCUSSION 54

4.1 Introduction 54

4.2 Mathematical Model 56

4.3 Experimental Setup 58

4.4 Result and Discussion 62

CHAPTER 5: CONCLUSION AND FUTURE WORK 66

5.1 Conclusion 66

5.2 Future Work 67

REFERENCES 68

APPENDIX

A Isometry View

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viii

LIST OF TABLE

TABLE TITLE PAGES

2.1 Numerical Values of The Parameters For Fluid Inn Each Inertia Track

3.1 Block Diagram/Symbols 45

3.2 Nomenclature of The Include Parameters 46

3.3 Simulink Model Parameters 48

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LIST OF FIGURE

FIGURE TITLE PAGE

2.1 Different Engine Mount Design 3

2.2 Engine Mounting System Technology Road Map

2.3 Rubber Mount and Hydro Mount 4

2.4 A Typical Single Pumper Hydraulic Engine Mount

2.5 Hydraulic Mount 7

2.6 Dynamic Stiffness of A Typical Hydraulic Engine Mount

2.7 Operation of Adaptive Hydraulic Mount 10

2.8 A Physical Model of An Elastomeric Mount 13 2.9 Mechanical Model of An Elastomeric Mount 13

2.10 Typical Elastomeric Mounts 14

2.11 Typical Rear Mount Installation 14

2.12 Dynamic Stiffness of An Elastomeric Mount 15

2.13 Physical Model of Hydraulic Mount 16

2.14 Mechanical Model of A Hydraulic Mount 17

2.15 Dynamic Stiffness of A Hydraulic Mount 18

2.16 Physical Model of A Hydraulic Mount 19

2.17 Mechanical Model of An Active Elastomeric Mount

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Mount

2.19 Dynamic Stiffness of An Active Hydraulic Mount

2.20 Mechanical Model of Semi-active Hydraulic Mount

2.21 Regular and Inertia Track Mount of Hydraulic Mount

2.22 Dynamic Stiffness of Double Notch Hydraulic Mount

2.23 Sketch Map and Measuring Load vs Displacement on Test Rig

2.24 Engine 6 DOF Mode 37

3.1 Process Flow Chart 41

3.2 Passive engine mounting system free body diagram

3.3 A Product of Assemble Test Rig 50

3.4 Experimental setup description 51

3.5 Accelerometer Sensor 52

3.6 MCP Electronics (Voltage Meter) 52

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4.1 Free Body Diagram Engine Mounting System (EMS)

4.2 Experimental setup description 59

4.3 Actual Test Rig with Unbalance Load Motor 59

4.4 MCP Electronics (Voltage Meter) Setup 60

4.5 Setup Accelerometer Sensor at the Mounting 60 4.6 Comparison between the simulation results

with the experiment results for the vertical acceleration with frequency input 9 Hz.

4.7 Comparison between the simulation results with the experiment results for the pitch moment acceleration with frequency input 9 Hz.

48 Comparison between the simulation results with the experiment results for the roll moment acceleration with frequency input 9 Hz.

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LIST OF SYMBOLS

Symbol Description

P(t) - Excitation Force

Me - Engine Mass

Mu - Unbalance Mass

Fs - Spring Force

Ks - Spring Constant

Cs - Damping Constant

Zs - Engine Unit Displacement

Zu - Chassis Unit Displacement

Żs - Engine Unit Velocity

Żu - Chassis Unit Velocity

- Engine Unit Acceleration

Fsf - Front Spring Force

Fsrr - Rear Spring Force

Fsr - Right Spring Force

Fsl - Left Spring Force

Fdf - Front Damper force

Fdrr - Rear Damper Force

Fdr - Right Damper Force

Fdl - Left Damper Force

P - Track Width

L - Wheelbase Length

Ksf - Front Spring Constant

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Ksr - Right Spring Constant

Ksl - Left Spring Constant

Csf - Front Damping Constant

Csrr - Rear Damping Constant

Csr - Right Damping Constant

Csl - Left Damping Constant

Zsf - Front Engine Unit Displacement

Zsrr - Rear Engine Unit Displacement

Zsr - Right Engine Unit Displacement

Zsl - Left Engine Unit Displacement

Zuf - Front Chassis Unit Displacement

Zurr - Rear Chassis Unit Displacement

Zur - Right Chassis Unit Displacement

Zul - Left Chassis Unit Displacement

Żsf - Front engine unit velocity

Żsrr - Rear engine unit velocity

Żsr - Right engine unit velocity

Żsl - Left engine unit velocity

Żuf - Front chassis unit velocity

Żurr - Rear chassis unit velocity

Żur - Right chassis unit velocity

Żul - Left chassis unit velocity

Mp - Pitching Moment

Mr - Rolling Moment

Ip - Inertia in Pitching

Ir - Inertia in Rolling

Θ - Pitching angle

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- Pitch acceleration

Α - Roll angle

- Roll rate

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1.1 Background

A car engine is connected with an engine mount on the car frame. An engine mount are usually made of rubber and metal. The metal portions are connected to the engine on the one side and to the frame on the other. The rubber is between an apparatus for controlling relative movement and engine mount housing to provide some flexibility. Now-a-days, most of the newer cars are used slightly different mounts. However, there purpose is still the same.

Generally, hydraulic engine mounts are used in aerospace and automotive application for the purpose of cabin noise and vibration reduction. The dynamic stiffness will be smaller at certain frequency than the static stiffness, cabin vibration and noise reduction. All the hydraulic mount design parameters are selected very carefully. This frequency is referred as notch frequency and it is provided at that frequency.

In this paper, passive hydraulic engine mounts will be modelled. An improved decoupler control is introduced that the mechanism steady state behaviour does not noticeably affect, but start up and transient response improves. Hydraulic mount design more effective and it is tuneable and the mechanism of decoupler design will be smaller and lighter.

INTRODUCTION

CHAPTER 1

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1.2 Project Problem Statement

1. The compatibility an engine mounts system to run on a test rig.

2. The proper method is needed to solve the dynamics vibration occurs on the test rig and the engine mounting.

1.3 Project Objective

1. To analyze engine mount system using a 3-DOF equation. 2. To model the engine mount system using MATLAB Simulink. 3. To validate the engine mount model with engine mount test rig.

1.4 Scope of Project

My research project will focus primarily on the functions of the passive engine mounting to be implemented on a test rig. An engine that attaches to unbalance load will be placed on a test rig. There will be four sensors that will be attached to the test rigs to detect the vibration, noise and harshness that is caused by motor or any mechanism of the engine parts. Then, the result obtained from MATLAB Simulink into the sensor will be applied.

1.5 Approach

My proposed report will begin with a brief review of the engine mounting. The report will then discuss how the passive engine mounting function or operate as a safety mechanism to be implemented on the vehicle’s chassis.

1.6 Result Expectation

1. Engine mount system using 3-DOF equation will be analyzed.

2. Manage to model passive engine mount system.

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2.1 Introduction

(a) (b)

(e) (f)

Figure 2.1: Different Engine Mount Designs. (a) Basic design (b) Two arm design (c) Three arm design (d) Four arm design (e) Filler arm design (f) Four arm symmetry design (Anynomous,ND)

Now-a-days, most of the cars are used slightly different types of design of the engine mounts as shown as in the Figure 2.1. However, the function and purpose is still the same. To give the driver and the passenger the comfort while experiencing the driving moment.

LITERATURE REVIEW

CHAPTER 2

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2.2 Types of Engine Mounts

Figure 2.2: Engine mounting system technology road map (Anynomous,ND)

Figure 2.3: Rubber Mount (On the left) and Hydro Mount (On the right) (Anynomous,ND)

EMS

Passive

Active

Rubber Hydro-Mount

Variable Decoupler Opening Variable Fluid Viscosity

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5 In Figure 2.2 shows that a system technology road map of engine mounting. Commonly an engine mounting looks like as shown in figure 2.3. Usually, a drivetrain car consists of the engine and transmission. The engine makes up a substantial bulk of a car’s weight, and where and automobile manufacturer decides to mount the engine directly impacts the vehicle’s performance. The position of the engine affects performance by setting the car’s moment of inertia, which is a physical property that determines, among other things, how quickly a car can turn (ehow.com, 2010). Car engine mounting are divided into 3 parts;

i. Front Mounted: Car manufacturers can mount a car’s engine in two ways. Front-mounted engines will be placed on in front or directly over the forward axle. A front-mid-mount is placed on the engine behind the front axle.

ii. Mid Mounted: The engine mount is placed on the rear axle, but behind the cab passenger seat. Cars with a mid-mounted engine use either RWD or AWD to transfer power to axles. The position of mid-mounted offers the lowest moment of inertia.

iii. Rear Mounted: Rear mounted engine is placed behind the back axle and behind the cab where the passengers sit. Cars with a rear-mounted engine transfer power to the axle with either RWD or AWD. This position of the engine mount will increase the moment of inertia and drivers must fight against over-steering during acceleration.

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Α - Roll angle

- Roll rate

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1.1 Background

INTRODUCTION

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2 1. The compatibility an engine mounts system to run on a test rig.

2. The proper method is needed to solve the dynamics vibration occurs on the test rig and the engine mounting.

1.3 Project Objective

1. To analyze engine mount system using a 3-DOF equation. 2. To model the engine mount system using MATLAB Simulink. 3. To validate the engine mount model with engine mount test rig. 1.4 Scope of Project

1.5 Approach

1.6 Result Expectation

1. Engine mount system using 3-DOF equation will be analyzed. 2. Manage to model passive engine mount system.

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3 2.1 Introduction

(a) (b)

(e) (f)

Figure 2.1: Different Engine Mount Designs. (a) Basic design (b) Two arm design

LITERATURE REVIEW

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4 Figure 2.2: Engine mounting system technology road map (Anynomous,ND)

Figure 2.3: Rubber Mount (On the left) and Hydro Mount (On the right) (Anynomous,ND)

EMS

Passive

Active

Rubber Hydro-Mount

Variable Decoupler Opening Variable Fluid Viscosity

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Design and validate passive automotive engine mount system.

UNIVERSITI TEKNIKAL MALAYSIA MELAKA