HBÁO CÁO NGHIÊN CỨU KHOA HỌC Đề tài: CONFIGURATION SYNTHESIS OF NOVEL STEERING AND SUSPENSION SYSTEMS WITH EIGHTLINK MECHANISM (Viết báo hệ thống treo Double Wishbone Nghiên cứu cấu hình của hệ thống treo với cơ chế tám liên kết)

Article about Double Wishbone Suspension System Graduation Thesis ĐẠI HỌC LẠC HỒNG KHOA CƠ ĐIỆN ĐIỆN TỬ BÁO CÁO NGHIÊN CỨU KHOA HỌC Đề tài CONFIGURATION SYNTHESIS OF NOVEL STEERING AND SUSPENSION SYSTEMS WITH EIGHT LINK MECHANISM (Viết báo hệ thống treo Double Wishbone Nghiên cứu cấu hình của hệ thống treo với cơ chế tám liên kết) PHAN TRÍ THIỆN HÀ ĐỨC TRƯỜNG VŨ VIẾT VƯỢNG Đồng nai, 062022 Page | 2 ĐẠI HỌC LẠC HỒNG KHOA CƠ ĐIỆN ĐIỆN TỬ BÁO CÁO NGHIÊN CỨU KHOA HỌC Đề tài CONFIGURATION SYNTHESIS.

ĐẠI HỌC LẠC HỒNG KHOA CƠ ĐIỆN ĐIỆN TỬ

(Viết báo hệ thống treo Double Wishbone - Nghiên cứu cấu hình của

hệ thống treo với cơ chế tám liên kết)

PHAN TRÍ THIỆN

HÀ ĐỨC TRƯỜNG

VŨ VIẾT VƯỢNG

Đồng nai, 06/2022

KHOA CƠ ĐIỆN ĐIỆN TỬ

(Viết báo hệ thống treo Double Wishbone - Nghiên cứu cấu hình của

hệ thống treo với cơ chế tám liên kết)

Chuyên ngành: Công nghệ Kỹ thuật Ô tô

NGƯỜI HƯỚNG DẪN KHOA HỌC

TS HOÀNG NGỌC TÂN

Đồng nai, 06/2022

LỜI CAM ĐOAN

Tôi xin cam đoan công trình nghiên cứu là của tôi, các số liệu, kết quả nêu ratrong đồ án tốt nghiệp là trung thực và chính xác

Tôi xin cam đoan mọi sự giúp đỡ cho việc thực hiện đồ án tốt nghiệp này đãđược xin phép, tất cả các thông tin trích dẫn trong luận văn đều được ghi rõ nguồngóc

Tôi xin hoàn toàn chịu trách nhiệm về những gì mà tôi đã cam đoan trên đây

Đồng nai, ngày 11 tháng 06 năm2022

Sinh viên thực hiệnPhan Trí Thiện

Hà Đức Trường

Vũ Viết Vượng

Thành viên nhóm vô cùng biết ơn quý thầy trong Khoa Cơ Điện-ĐiệnTử_Trường Đại học Lạc Hồng, đặc biệt là Thầy hướng dẫn TS Hoàng Ngọc Tân đãgiúp đỡ, hướng dẫn nhiệt tình và đóng góp quan trọng trong việc nghiên cứu đề tài.

Xin trân trọng cảm ơn!

Đồng nai, ngày 11 tháng 06 năm2022

Sinh viên thực hiệnPhan Trí Thiện

Hà Đức Trường

Vũ Viết Vượng

TABLE OF CONTENTS

1 Introduction 1

2 Existing mechanism design 3

3 Generalization 5

4 Synthetic chains 6

5 Specialization 6

a Frame link (KF) 7

b Shock absorber (KT) 7

c Rack and Rod (KR) 8

d Steering link (KS) 9

e Two wishbone arms (KUA and KLA) 10

6 Particularization chains 12

7 Atlas of new designs 14

8 Simulation 14

9 Mathematical Simulation 16

10 Modeling of the Double Wishbone Suspension Wishbone using Simulink 17

11 Conclusion 19

References 20

Figure 1 Different types of suspension systems 1

Figure 2 Structural model of the double wishbone suspension [2] and its mechanism 4

Figure 3 Generalized chain of the double wishbone suspension 5

Figure 4 Atlas of (8,10) generalized chains 6

Figure 5 Structure chains with identified frame link and shock absorber 8

Figure 6 Specialized chains with identified frame link, shock absorber, and rack and rod 9

Figure 7 Specialized chains with identified steering link 9

Figure 8 Atlas of feasible specialized chains 11

Figure 9 Atlas of double wishbone suspension mechanism 14

Figure 10 Suspension system on CATIA 15

Figure 11 Suspension deflection 16

Figure 12 The Double wishbone suspension model 16

10 Modeling of the Double Wishbone Suspension Wishbone using Simulink 17

Figure 13 Modeling of The Double wishbone suspension using Simulink 18

Figure 14 Acceleration of The Double wishbone suspension for mixture of Ka=1500 and Ca=30 18

Contents lists available at ScienceDirectMechanical Systems and Signal

Processingjournal homepage: www.elsevier.com/locate/mssp

Configuration Synthesis of Novel Steering and Suspension Systems with Eight-Link Mechanism

Ngoc-Tan Hoang*, Tri-Thien Phan

Faculty of Mechatronics and Electronics, Lac Hong University, 10 Huynh Van Nghe Street, Buu Long ward,

Bien Hoa City, Dong Nai Province, Vietnam.

As a result, the most significant component in developing a new mechanism complieswith needs and limits The results in this study increase the vehicle's handlingqualities such as possible traction and maneuverability

Keywords: Steering and suspension systems, 8-links and 10-joints mechanisms,double wishbone, configuration synthesis, suspension simulation

1 Introduction

The system connects the body of the vehicle (chassis) to the wheels of thevehicle, allowing the vehicle to move stably between the components, thereby makingthe vehicle resistant to shocks on the road surface Shock absorbers (dampers), springsets, connections, and air-damped tires take up the shock, providing bettergrip/handling and handling for occupants during heavy braking or into the crabs Themost optimal goal is that the suspension system must make all the wheels in the mostoptimal contact with the road surface because the contact pads receive all the forcesand reactions from the road surface to interact with the vehicle What's more, thissystem reduces weight on the wheels and this also reduces tire wear, helping toprolong the working life of the vehicle economically

Types of Suspension System

Coil Spring Leaf Spring

Torsion Bar

MacPherson Strut Double wishbone

Verticle Guide Trailing Arm Swing Half Axles Solid Axle

Independent Suspension Systems

Dependent Suspension Systems

Figure 1 Different types of suspension systems

Springs have a certain ratio when used in suspension The spring elasticity,scientifically known as the spring constant, is an important criterion for determiningthe resistance and stiffness of the spring when providing it with a force or a weightwhen the spring is deflected

Article about Double Wishbone Suspension System Graduation Thesis

When the vehicle is operating on rough terrain, the vehicle goes up and downcausing damage to components And to reduce the damage to optimize the parts theyhave been divided into two separate zones as follows:

1.Suspension dynamics

2.Suspension kinematics

The dynamics of the system depend a lot on the road conditions, and the forcesacting when the vehicle is operating Thereby, it is possible to come up with newsolutions and choose the right type of suspension, the solution used is to combinedamper to optimize the above values Therefore, showing the dynamics of thesuspension system when the vehicle is operating up or down at the point of change ofposition and stroke length, it should be placed at a reasonable point To consider this,

we should choose different types of materials, change the properties of the materials,and evaluate the effectiveness of the structure Provide good manageability for thevehicle, and bring higher efficiency compared to other materials along with theadvantages of the vehicle

Double wishbone is a famous suspension layout for excessive overallperformance vehicles, the suspension mechanism may be composed of mechanisms:

a four-bar, and a five-bar, that are linked at the principle pin The double-wishbonesuspension turned into recognized withinside the 1930s This system has been usedfor Rosalie and Traction Avant model in 1934 by the French carmaker The use of adouble-wishbone system makes it easier to manage wheel roll motion in alltraversing, manage wheel angle, learn toe, and a few other parameters

Nowadays, technology is gradually developing, the systems become morecomplex but provide a high level of efficiency, vehicle suspension is a typicalexample The main function of the suspension is to meet stability, maneuverability,and safety This system is responsible for maintaining continuity between the roadsurface and the wheel provides stability and protection of the chassis when traveling

on uneven roads and brings comfort to the driver when navigating The structure ofthe suspension consists of three main components: the elastic part (reducing the

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frequency of oscillation, ensuring smoothness when passing uneven roads), thedamping unit (increasing the sale of wheels, avoiding strong vibrations), guides(transmission and moment between wheels and chassis) The goal of the current job is

to focus on a specific suspension system, the double-wishbone suspension with 8links, which is very popular on vehicles This system has two clavicle-shaped arms toposition the wheel, each structure is attached to the frame and joints at the knuckle bytwo points

EXISTING MECHANISM DESIGNS

Figure 1 Procedure of configuration synthesis.

2 Existing mechanism design

The double-wishbone suspension is distinguished by its superior dynamics andload management characteristics As a result, this technology has been discovered inracing automobiles and sports cars throughout history Double wishbone suspension

Article about Double Wishbone Suspension System Graduation Thesis

was first introduced in 1930 and is now utilized by several car manufacturers likeMercedes-Benz, MG, and Pontiac On the Honda NSX and Honda Prelude, doublewishbone suspension was used both in the front and rear Figure 1 shows a typicaldouble-wishbone suspension design

Figure 2 Structural model of the double wishbone suspension [2] and its mechanism

The structure and linkage of the double-wishbone suspension are as follows :

1 It is a spatial device with eight links and ten joints

2 It uses the frame link (link 1, KF), the upper arm (link 2, KUA), the steeringlink (link 3, KS), a lower arm (link 4, KLA), a shock absorber (KT) has a cylinder(link 5, KY) and a piston (link 6, KI), a tie rod link (link 7, KTR), and a rack link(link 8, KR)

3 It has four rotating links (joints a, b, c, f; JR), four spherical pairs (joints d, e, h,i; JS), and two prismatic pairs (joint g, j; JP)

4 The DOF of the double-wishbone suspension mechanism is

Fs = 6(NL – 1) –[NJRCJR + NJPCJP + NJSCJS + NJUCJS]

=6(7 – 1) – [4*5 + 2*5 + 2*3 + 1*4] = 2

The mechanism possesses

Degrees-of-freedom: The first one is calculated for the navigation inputs, and thesecond may be jounce and rebound, modeled as the street profile enter y

The topological matrix (MT) of double wishbone suspension is:

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1 The frame link (link 1) is a structure with the quaternary link

2 The upper wishbone arm (link 2) is a structure with the binary link

3 The steering link (link 3) is a structure with the ternary link

4 The lower wishbone arm (link 4) is a structure with the ternary link

5 The cylinder (link 5) and the piston (link 6) of the shock absorber are generalized

in to a dyad (binary link 5 and 6)

6 The tie rod (link 7) is a structure with the binary link

7 The rack (link 8) is a structure with the binary link

Article about Double Wishbone Suspension System Graduation Thesis

As a result, the double wishbone suspension's corresponding generalized chain,illustrated in Figure 2b, has 8 generalized links and 10 generalized joints, as shown inFigure 3

RJ

RJ

e

fa

bd

g

hi

j

F K

UA K

S K

c

LA K

Y K

I K

T K

R K

Figure 3 Generalized chain of the double wishbone suspension

4 Synthetic chains

The algorithm of number synthesis will be used to synthesize the atlas ofstructure chains that have the same number of links and joints from the generalizedchain of the above current design

Using the atlas of generalized chains in the book [3], there is a total of 40generalized chains shown below

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Figure 4 Atlas of (8,10) generalized chains

5 Specialization

The following are the needs and constraints for the double-wishbone suspensiondesign:

Requirements:

1 There should be a frame link

2 There should be a shock absorber

3 There should be a steering link

4 There should be two wishbone arms

5 There should be a pair of rack links and tie rod

6 The frame link, the shock absorber, steering link, and pair of rack and rod linksshould be distinct members

Constraints:

1 Two spherical joints on the steering link form an axis of a universal joint

2 The steering link and the frame link should not be connected

3 The frame link is a ternary link or quaternary link

4 The steering link is multiple links (ternary link) the shock absorber is a pair ofdyad link

All possible practicable specialized chains are identified as follows from the Atlas of(8,10) generalized chains illustrated in Figure 3:

Article about Double Wishbone Suspension System Graduation Thesis

to the frame link at the same time The shock absorber can be selected from a set of

40 figures that include at least two binary links

No.2 No.3 No.4 No.8 No.9 No.10 No.11

No.12 No.13 No.14 No15 No.21 No.23 No.24

No.25 No.26 No.31 No.32 No.33 No.34 No.36

No.38 No.37

Figure 5 Structure chains with identified frame link and shock absorber

The figures had the decide huge range are No 2, No.3, No.4, No.8, No.9, No.10,No.11, No.12, No.13, No.14, No.15, No.21, No.23, No.24, No.25, No.26, No.31,No.32, No.33, No.34, No.36, No.37, and No.39 will qualify to be recognized because

of the wonder absorber They are general of 23 possible designs shown

c Rack and Rod (K R )

Because the piston and cylinder will form a pair of dyad links, a shock absorberwill be generated The two pieces are the piston and cylinder, which are not attached

to the frame link at the same time The shock absorber can be selected from a set of

40 figures that include at least two binary links The specialized chains with identifiedframe links and shock absorbers are shown in the figure 5, the figures having 2 pairs

of the binary link will be chosen

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No.2 No.3 No.4 No.23 No.24

Figure 6 Specialized chains with identified frame link, shock absorber, and rack and rod

Therefore, ten specialized chains with determined frame link, shock absorber, and apair of racks and rods are shown in figure 6

d Steering link (K S )

Figure 7 Specialized chains with identified steering link

The steering link should not be close to the frame link and should be a ternary link.The No 36, No 37, and No 39 figures from Figure 6 will be published As a result,there are seven qualifying design requirements for specialty chains, as shown inFigure 7

e Two wishbone arms (K UA and K LA )

At least one of the two wishbone arms will be next to the steering link As a result,the specific chains depicted in Figure 7 will meet the design requirement

Article about Double Wishbone Suspension System Graduation Thesis

We obtain the result of feasible specialized chains according to the method ofspecialization and satisfy all of the requirements and restrictions after choosing thepattern of links and joints for each generalized chain as shown in Figure 7 Inconclusion, there are all eleven possible chains form the atlas of possible specializedchains shown in Figure 8

jcb

a1

6 Particularization chains

Article about Double Wishbone Suspension System Graduation Thesis

We have a comparable structure for each of the eleven possible specialized chains

in Figure 8, resulting in the atlas of mechanical devices illustrated in Figure 9

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g) h)

MacPhenrson front suspension

k) Double wishbone suspension Figure 9 Atlas of double wishbone suspension mechanism

Article about Double Wishbone Suspension System Graduation Thesis

7 Atlas of new designs

From eleven of atlas of double wishbone suspension mechanism in Figure 9, two

of them is the same with the existing design (Figure 9.j and 9.k) Therefore, theremaining nine design concepts as shown Figure 9.(a), (b), (c), (d), (e), (f), (g), (h),and (i) are new for double wishbone suspension of automobile

8 Simulation

The wishbone suspension is a combination of components with high strength andconnectivity and is designed to keep the center of gravity of the main shaft as close tothe vehicle's center of gravity as possible Recent developments in suspensionsystems have centered on increasing vehicle ride quality and handling To develop adouble-wishbone suspension system, CATIA is employed for analysis and simulation(CATIA did the modeling of elements and assembly) By changing the length of thecamber, the length of the A-arm, and the system's 8-link mechanism Along with that

is the study and design of parameters such as the inclination of the wheel, the clampbase, and the meniscus to link with the collarbone The A-links are designed andmanufactured with good bearing materials, can withstand large bending forces, andimpact forces of agents when the vehicle is moving and the material chosen here issteel The goal and design process is to combine many factors such as load factors,shape, and aesthetics into a suitable level Thereby choosing the right material interms of durability and cost reduction is the leading criterion in the manufacturingindustry From the above factors, we can choose and design a suspension system that

is more stable and better than commercial products

To evaluate the effectiveness of the designed suspension system, the simulationhad been built on CATIA shown in Figure 10

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