2014FSC悬架答辩报告-太原理工

独特创新设计A

Unique

Design多连杆独立悬架Multi-link

Suspension————————太原理工大学晋翔车队Taiyuan

University

of

Technology

JX

Racing

Team独创“瞬轴设计法”Create

A

New

Method动态性能出众High

Performance自主探索总结出多连杆悬架导向机构设计“瞬轴法”和转向回正力矩计算方法，充分发挥了多连杆悬架的优势，提高了赛车的操控性能During

this

process,we

found

a

new

way

for

the

design

of

multi-link

suspension

byourselves,and

this

method

can

be

used

for

nearly

all

kinds

of

independentsuspension.太原理工大学JX.1赛车悬架采用了大学生方程式中极少用到的多连杆独立悬架，其设计过程经过了运动学优化（包括悬架运动时的车轮及主销定位参数变化、侧倾中心布置及载荷转移等参数变化）、动力学优化（包括转向力、反馈力等）、轻量化设计和制造成本优化JX.1racing

car

of

TYUTwas

designed

using

multi-linksuspension，which

is

hardlyused

in

Formula

Student.

Wedesigned

it

with

consideringof

kinematic，dynamic，lightweight

and

producingcost

optimizing.——————————————————————————概述SummaryWhy

is

multi-link?高性能Performance调节自由Adjustable设计自由度Design

Possibilities受力良好Force

Situation面向制造节约成本Easier

produce

and

Less

costFirst

of

all,

Formula

Student

is

a

engineering

design

competition

aiming

to

train

us

new

guys,

so

whywe

try

something

new?

Why

don’t

we

try

to

learn

more

from

this?多连杆独立悬架拥有更多的控制臂，因此，精心设计的多连杆悬架可以提供更好的操控性能。Amulti-link

suspensioncontains

more

links

sothat

it

can

supply

betterhandling

performance

whenelaborate

designed.—

—

—

—

—

—

—

—

—

—

—

—

—多连杆悬架在很多高性能汽车上得到应用，例如大众辉腾、宝马3系和5系、以及奔驰C级，他们的前后悬架均为多连杆形式。In

fact

there’s

many

high

performance

cars,

such

as

Volks

Wagon

Phaeton

,BMW

3

Class

and5

Class,

and

Mercedes

E

Class,

use

multi-link.

Besides,

without

bushings,

a

racing

car

withmulti-link

will

have

less

problems.杆系受力Force

Situation双叉臂悬架的A臂看似是一个结构稳定的三角形，但事实上由于焊接、应力、铰接等需求，A臂要想受力良好需要更多的工作和成本。There’s

always

bending

force

on

an

A-arm.

An

A-arm

seems

like

a

steady

triangle,

but

in

fact

it’sweld

at

end,

so

that

the

force

can’t

betransfered

perfectly

along

bar

direction,

and

itmay

cause

some

trouble

at

the

hardpointconnecting

A-arm

and

upright.多连杆悬架的所有杆件均为二力杆，杆件结构简单，制造方便，成本低廉。All

the

control

arm

in

multi-link

suspension

aretwo-force

members

with

simple

structure,

whichmeans

we

can

use

thinner

bars,

cheaperballjoints，and

less

cost

for

producing.

It

doesgreat

help

for

lightweightand

volume-produce.设计空间Design

Possibilities试想，三维空间中的五个杆件可以组合多少种可能？更多的连杆提供给了我们更大的设计空间。多连杆悬架可以实现更好的性能，也能实现更自由的布局。这提供给设计者更多的方便，可根据需要自由协调平衡。同时，设计自由度更大的多连杆悬架可能让你的车看起来的确与众不同。Try

to

imagine

what

amazing

can

be

done

with

five

links

in

3D

space?

More

control

arms

supply

usmore

possibilities

in

design

than

only

two

A-arms.

Multi-link

can

achieve

better

performance(suchas

steering

wheel

feed

back,

and

kinematic

stuff)

or

better

package,

you

can

balance

it

duringthe

design.自由调节AdjustableDouble

A-arm

often

has

fixedstructure,

or

use

some

complexdesign

to

make

it

adjustable,

andmost

of

them

cannot

adjustcamber

and

kingpin

inclinationseparately.双A臂悬架通常具有难于调整

的结构，或者需要更复杂一点

的设计来实现某个参数的可调。由于多连杆悬架没有实际的主

销，它可以通过调节控制臂的

长度来实现车轮和主销定位参

数的调整。在不同的比赛中，

只需拧拧螺母就可以实现定位

参数的微调。Multi-link

can

be

adjust

all

of

camber,

kingpin

inclination,

and

kingpin

caster,

becausethere’s

no

actual

kingpin.

The

virtual

kingpin

moves

when

change

length

of

a

control

arm.瞬轴法Instant

Axle

Method多连杆悬架的控制臂通常是空间交错的，“虚拟”的主销轴线位置的确定本Where’s

the

kingpin身n就？是一个课题。我们独立提出了一种新的“瞬轴法”设计多连杆悬架的方法。这种

“瞬轴法”通过基础的三维建模，将复杂的空间解析问题用几何法

表达了出来，不仅直观可见，而

且方便于对其运动学和动力学规

律的研究，已经形成从“零”开始的整套多连杆悬架设计流程。A

wheel

moves

around

an

axis

called

instant

axle

at

certain

time

when

it’s

jumping

or

rebounding,

and

th

is

some

kindofgeometrical

relationship

between

control

arms

and

the

instant

axle.

Using

this

method

we

can

find

where

is

the

kingpinofa

certain

suspension,

but

also

do

it

in

opposite

direction.

You

know

the

instant

axle

does

a

lotofinfluences,

so

we

fix

instant

axle

firstly,

and

place

control

arms

by

followin

geometrical

relationship

anywhere

we

want.

This

process

can

be

done

easily

and

visually

with

a

softwareCATIA(everybody

can

use

CATIA).瞬轴法Instant

Axle

MethodIt’s

not

easy

to

design

a

multi-link

suspension,

especially

when

thewheels

are

traveling,

everything

you

designed

in

static

conditionchanges

causing

more

data

to

deal

with.

We

did

it

only

by

a

basaland

popular

software,

CATIA.

It

might

looks

stupid,

but

what

we

didis

quite

meaningful

for

us

to

understand

theory

and

principle

ofsuspension.由于悬架的跳动，产生的大量动态特性数据将使设计变得十分困难。在这里我们只用了最基础的软件——CATIA，来处理这些问题。这样一种最简单最基础的计算机辅助，对使我们更好地了解悬架理论起到了重要作用。力反馈Force

feedbackIn

a

Formula

Student

racing

car,we

don’t

have

EPS.

But

steeringforce

and

force

feedback

areimportant

for

feeling

and

controlthe

car.

At

this

point

we

also

cameup

with

a

way

found

by

ourselvesto

calculate

it.在大学生方程式的赛车上，我们没有电子助力转向，但是转向力和方向盘力反馈对于操控车辆来说又十分重要。对此，我们找到了一种计算转向力和力反馈的方法。同时，通过这种方法，我们也清晰地了解到了力反馈产生的机理。It

also

only

used

CATIA,

but

none

of

simulation

software.

The

method

we

found

used

calculationfunction

of

CATIA,

and

we

made

both

velocity

and

force

visible.力反馈Force

feedbackThis

is

a

sheet

containing

what

wemeasured

from

the

model

and

results

wegot

by

calculation.

Finally

we

got

a

sheetlike

right右面的表格包含了从CATIA数模中测量的项目和计算的结果，最终我们可以借此得到某一工况下。转向力和力反馈的结果—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—力反馈Force

feedback我们计算了三种工况下的转向

力和力反馈——高速小G值、中速中等G值、和大G值，分别用

于评估车辆的高速直线行驶稳

定性、以及在常用工况和极端

工况下的转向操纵性。最终我

们得到每种工况下的力或力矩，并通过等效来让驾驶员在设计

的早期体会这个力值。This

We

calculated

threeconditions,

high

speed

and

lowlateral

G,

middle

speed

andmiddle

G,

and

high

G,

to

evaluatestraight

ahead

controllabilityand

cornering

controllability.We

can

get

a

torque

or

a

forcevalue

finally.—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—

—推杆Shock

Absorber

Pushing

Rodwe

used

a

pushing

rod

for

a

shock

absorber.Unlike

a

double

A-arm

suspension,

the

pushing

rodmoves

if

steering,

but

not

rolling.

It

might

lift

oneside

of

the

car

and

dive

the

other

side,

makingstee