aett zg 524-l1

8/18/2019 AETT ZG 524-L1

http://slidepdf.com/reader/full/aett-zg-524-l1 1/23

Vehicle Dynamics – Lecture-1

A course on Vehicle Dynamics

By

1Confidential

Prof. Sarvesh Mahajan BITS, PILANI

8/18/2019 AETT ZG 524-L1



Wha is his course all a!ou "

Hand-out-Vehicle

2Confidential

-Dynamics

8/18/2019 AETT ZG 524-L1



Inro#ucion o Auomoive Vehicles $

Automobile is a self-propelled passenger / commercial vehicle that

usually has to ! three! four or more heels and an internal-

combustion engine! used for land transport"

An automobile #or automotive$ is a vehicle that is capable of

%Confidential

"

&ince seventeenth century! several attempts have been made to

design and construct a practically operative automobile"

'oday! automobiles play an unimaginable role in the social! economic

and industrial groth of any country"

8/18/2019 AETT ZG 524-L1



%lassificaion of Auomoive Vehicles $

Base# on &ur&ose(

1" Passen'er vehicles – 'hese automobiles carry passengers – e"g"(

)uses! *assenger trains! cars2" (oo#s vehicles – 'hese vehicles are used for transportation of

goods from one place to another" e"g"( +oods lorry! goods carrier

,Confidential

8/18/2019 AETT ZG 524-L1




Base# on ca&aciy(

1" )eavy Moor Vehicle *)MV+ – Large and buly motor vehicles –

e"g"( Large trucs! buses2" Li'h Moor Vehicle *LMV+ – &mall motor vehicles – e"g"( Cars!

.eeps

– –

Confidential

" " "

trucs! mini buses

8/18/2019 AETT ZG 524-L1




Base# on fuel source(

1" Perol en'ine vehicles – Automobiles poered by petrol engine –

e"g"( scooters! cars! mopeds! motorcycles2" Diesel en'ine vehicles – Automotives poered by diesel engine –

e"g"( 'rucs! )uses

– –

Confidential

'urbine poered cars," Solar vehicles – Vehicles significantly poered by solar poer –

e"g"( &olar poered cars

" )y#ro'en vehicles – Vehicles that have hydrogen as a poer

source – e"g"( 3onda 4C5 Clarity

8/18/2019 AETT ZG 524-L1




Base# on fuel source(

" lecric vehicles – Automobiles that use electricity as a poer

source – e"g"( 6lectric car! electric buses7" Seam n'ine Vehicles – Automotives poered by steam engine –

e"g"( &teamboat! steam locomotive! steam agon

–

7Confidential

sources – e"g"( 3ybrid buses! hybrid cars lie 'oyota *rius! 3onda9nsight

:" )y!ri# lecric Vehicle *)V+ – Automobile that uses both 9nternal

Combustion 6ngine and 6lectric *oer &ource to propel itself – e"g"(

.aguar C-57

8/18/2019 AETT ZG 524-L1




Base# on y&e of ransmission-

1" Auomaic ransmission vehicles – Automobiles that are capable

of changing gear ratios automatically as they move – e"g"( Automatic'ransmission Cars

2" %onvenional ransmission vehicles – Automotives hose gear

8Confidential

%" Semiauomaic ransmission vehicles – Vehicles that facilitatemanual gear changing ithout clutch pedal"

8/18/2019 AETT ZG 524-L1



:Confidential

8/18/2019 AETT ZG 524-L1




Base# on num!er of /heels(

1" T/o /heeler – Automobiles having to heels – e"g"( &cooters!

motorcycles2" Three /heeler – Automotive having three heels – e"g"( 'ricycles!

Auto ricshas! 'empos

– –

1;Confidential

," Si1 /heeler /ih MuliA1les – Automobile having si< heels usedfor heavy transportation – e"g"( Large trucs! large buses

8/18/2019 AETT ZG 524-L1




Base# on he si#e of #rive-

1" Lef han# #rive auomo!ile – Vehicle in hich steering heel is

fitted on the left hand side – e"g"( Automobiles found in =&A! ussia2" 2i'h han# #rive auomo!ile - Vehicle in hich steering heel is

fitted on the right hand side – e"g"( Automobiles found in 9ndia!

11Confidential

people$

8/18/2019 AETT ZG 524-L1




Base# on /heel #rive-

1" 0ron Wheel Drive – Vehicle in hich *oer is supplied to the

4ront ?heels e"g" most of the passenger cars here the 4A? isalays higher

2" 2ear Wheel Drive - Vehicle in hich *oer is supplied to the ear

12Confidential

mostly higher%" 0our Wheel Drive - Vehicle in hich *oer can be supplied either

to the 4ront heels or ear ?heels or all , heels e"g" most of the

&=V@s

," All Wheel Drive - Vehicle in hich *oer is supplied to all , heels

alays e"g" most of the &=V@s run in desert areas"

8/18/2019 AETT ZG 524-L1



1%Confidential

8/18/2019 AETT ZG 524-L1




Base# on Bo#y %onsrucions-

1" Monoco3ue – Vehicle in hich Chassis 4rame is an integral part of

the )ody and all a<les and suspensions are mounted to it e"g" most ofthe passenger cars"

2" La##er 0rame *Bo#y over %hassis consrucion+ - Vehicle in hich

1,Confidential

suspensions are mounted to it and )ody is also mounted on it e"g"most of the passenger commercial Vehicles"

8/18/2019 AETT ZG 524-L1



Auomoive Vehicle consrucion $

I consis of follo/in' Major Sysems $

1"$ )ody2"$ Chassis 4rame #if vehicle is ladder frame based$

%"$ &uspensions

1Confidential

"$ A<les! ?heels and 'yres and )raes"$ 6ngine and *oer 3ouse

7"$ Drive Line #consist of +ear )o<! *rop shaft! Differential! Clutch etc"$

8"$ Cooling and 6<haust &ystem

8/18/2019 AETT ZG 524-L1



Auomoive %hssis consrucion $

1Confidential

8/18/2019 AETT ZG 524-L1



Auomoive Bo#y consrucion $

17Confidential

8/18/2019 AETT ZG 524-L1



Im&orance of Vehicle Dynamics $

Vehicle dynamics is a part of engineering primarily based on classical

mechanics" 'he role of Vehicle Dynamics is very crucial in

understanding the overall running behaviour of the vehicles on raod"

Is major com&onens are $

18Confidential

u omo e ayou

6lectronic &tability Control #6&C$

&teering

&uspension

'raction control system #'C&$

8/18/2019 AETT ZG 524-L1



Some ari!ues of vehicle #ynamics are &urely aero#ynamic. Theseinclu#e-

Automobile drag coefficient

Automotive aerodynamics

Center of pressure

1:Confidential

+round effect in cars

8/18/2019 AETT ZG 524-L1



Some ari!ues or as&ecs of vehicle #ynamics are &urely 'eomeric.

These inclu#e-

Acermann steering geometry

A<le trac

Camber angle

Caster angle

2;Confidential

ide height

oll center

&crub radius

&teering ratio

'oe and ?heelbase

8/18/2019 AETT ZG 524-L1



Some ari!ues or as&ecs of vehicle #ynamics are &urely #ueo mass an# is #isri!uion. These inclu#e-

Center of mass

oment of inertia

oll moment

21Confidential

=nsprung mass

?eight distribution

8/18/2019 AETT ZG 524-L1



Some ari!ues or as&ecs of vehicle #ynamics are &urely #ynamic.These inclu#e-

)ody fle< and )ody roll

)ump &teer

Directional stability

22Confidential

!

Boise! vibration! and harshness

*itch and ide uality

=ndersteer! oversteer! lift-off oversteer! a and fishtailing

?eight transfer and load transfer

8/18/2019 AETT ZG 524-L1



Some ari!ues of vehicle #ynamics can !e ari!ue# #irecly ohe ires. These inclu#e-

Circle of forces! Cornering force ! adial 4orce Variation

Contact patch! +round pressure and Camber thrust!

ela<ation length

2%Confidential

&elf aligning torue

&lip angle

&teering ratio

aett zg 524-l1

Documents