Suspension System Assignment

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Running head: SUSPENSION SYSTEM
Dynamic effect on vehicle passengers

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Running head: SUSPENSION SYSTEM
Contents
Introduction.................................................................................................................... 3
Procedure and Measurement method..................................................................................... 4
Information of survey data.............................................................................................. 5
The measuring devices for the acceleration and survey of data will be located
along the highway far from residential houses, in order to reduce noise................5
RESULTS ANALYSIS AND DISCUSSION........................................................................6
Numerical manipulation of data from the graphical representation................................................8
Calculation of period..................................................................................................... 8
Root Mean Square Amplitude (RMS)................................................................................. 9
Lower pass filter........................................................................................................... 9
Determination of weighted R.M.S...................................................................................10
Maximum transient vibration......................................................................................... 10
Maximum allowable driving time...........................................................................11
Improvement of modification of car suspension component.................................12
CONCLUSIONS.......................................................................................................... 13
References............................................................................................................... 14

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Running head: SUSPENSION SYSTEM
Introduction
The survey carried out by highway engineering on the lateral acceleration of vehicles and the
determination on change rules aligned with their distribution and their influence factors will need
intensive work, the importance of studying the lateral acceleration of a moving vehicle is it is
very possible to convert the acceleration into lateral force coefficient of a highway, that is the
pivotal factor for lateral stability and safe driving, another importance also through a comparison
with permissible value of acceleration that will ensure human being comfort and caretake on the
health hazards through evaluating the rationality of highways super elevation, this will
possibility help to determine ranges of super elevation ratios , the third importance is that lateral
acceleration is directly proportion to stability of a vehicle, that involves the driving character in a
curve, for example the identification of trajectory and velocity are greatly affected by the
magnitude of the lateral force acting on the driver , Fourthly, being a pivotal measurement of
lateral comfort, the lateral acceleration will have a vast relation with horizontal alignment of a
highway, and the model that bounds the two, that is lateral acceleration and the alignment of a
highway has possibility of being used to predict the lateral comfort of a route scheme in the
design stage, this is of great aid to improve the geometric design for better performance.
Recently, lateral acceleration has been studied from several viewpoints entirely on the world., for
example is on the lateral accelerations of a passenger car on an interchange ramp, a ring road of a
city expressway, and a rugged mountain.

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Running head: SUSPENSION SYSTEM
Procedure and Measurement method
The performance data of the passenger cars were measured using an MTi micro- inertial attitude
heading reference system1. Nine types of data were collected; which included, pitch angular, 3 -
axis acceleration, pitch angular velocity, yaw, roll angle, and roll angle velocity.
In whole study, the lateral acceleration is analyzed. The piezoelectric (PE) sensors was installed
on the floor of the vehicle, and about 24 hours was spent in calibrating and commissioning the
instruments in order to reduce the error.
The piezoelectric (PE) sensors will be used to determine the acceleration of the passenger car
driving along a small section of the Yankee flat Road, the piezoelectric uses piezoelectric effects
of sensing element to produce a charge output, and the advantage of choosing this type of
method is because its operation does not require any external power source, with components
such as crystals or ceramics and a few polymers, which is applicable as a sensing element to
provide a given number of electrons that will be proportion to the amount of stress applied.
The piezoelectric sensors also have a dipole when unstressed. This leads to generation of fields
from the stresses or temperature that will cause either piezoelectric or pyroelectric output.
Mobile electrons that are free to move from one phase to another through the signal condition,
are produced by generating electric field along the direction of the dipole or metallic electrodes
on its faces at its opposite extremes of the gradient, its capable of cancelling the generated field.
Voltage are not measured externally but the charges are measured using charge converter having
a higher impedance and also with a capacitor as its feedback. The output it produces is directly
proportion to the charge which occurs at the input and its feedback capacitor, but all this has no
resulting effect impacted by input capacitance of the transducer or attached cables. The
frequency always will be injected by feedback capacitor and resistor in a charge converter. The
transducer will suffice for most vibration measurements if more time constants are long enough.
Fig. The feedback capacitance of a charged converter
1 Beall, Chris, Ta, Duy-Nguyen, Ok, Kyel, ... Frank. (2012).
Attitude Heading Reference System with
Rotation-Aiding Visual Landmarks. Georgia Institute of Technology