Vehicle dynamics is analytical and practical science that is
used to study about the various motion of vehicle in a certain condition and
how different part of the vehicle response in those conditions. Like if a
vehicle turns from a sharp corner then how it behave, how it’s different
components react to this situation. Vehicle dynamics include mathematical
equations which are used to calculate optimum values of speed, friction
downforce etc in formula cars.
Vehicle dynamics includes various different topics which are
used to make a comfortable and safe car for race. Some of main topic are these.
BEHAVIOUR OF TYRES
GEOMETRY OF CHASIS
In this report I discuss mainly suspension
system of a formula car.
The suspension of a modern Formula car forms the critical
interface between the different elements that work together to produce its
performance. Suspension system is required to prevent the car from bumps and it
is also needed for creating better traction on tyres during the cornering, it
is also required for better control on the car.
In a race ,race cars experience various type of moments
during different-different time. Like pitch(the moment which is generated in
y-axis during braking), roll(moment which generated in x-axis during cornering),
yaw(moment which is generated in z-axis).
To prevent the action of these moment a good suspension
For understanding the suspension system we need to know some
basic terms that are used to defined whole suspension system.
CAMBER- When we see
the tyre from front ,it is the angle between vertical axis and the axis at
which tyre is aligned. If the tyre of the car is in right side of the car then
it is said to be positive camber ,and if it is in left side it is said to be
Usually negative camber is required for a race car during
cornering it increases the grip of tyres during turn. Camber is adjustable in
every car having a wishbone suspension.it is also helful in decreasing height
of the car.
STEERING AXIS- It is the axis about which tyre rotate when
it is turning in a corner. Mainly steering axis is inclined with the vertical
axis. It is inclined for decreasing the scrub radius of suspension system.
(scrub radius is distance between steering axis and the axis of the tyre ) by
decreasing the scrub radius torque required to rotate the wheel is decrease and
we can easily rotate the wheel about steering axis. It also help the wheel to
come back its initial position.
CASTER- When we saw a car from side view, then it is the
angle between the steering axis and the vertical axis. If the steering axis is
in right side of vertical axis it is said positive caster and if in left side
it is said to be negative caster. Most of the car have negative caster
Because it helps the wheels to come back its own position.
These are some important terms used in suspension system.
A simple suspension is consist of spring and a damper. When
a shock is comes then spring convert that energy into potential and damper
convert it to the heat energy and dessipitate it to the atmosphere.
Suspensions are divided into two type 1 Independent
suspension( in this shock of the one side wheel not cause any action in second
wheel) 2 Dependent suspension(in this shock of one side wheel also affect the
adjacent portion of car .
There are many type of suspension system some of them are