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1. CRASH IMPACT ATTENUATOR (CIA) FOR AUTOMOBILES WITH THE
ADVOCATION OF MECHATRONIC SYSTEMS
[1]M.ASHWIN, [2] BHUVANESWARAN P, [3] VARUN.C
[1]SRM EASWARI ENGINEERING COLLEGE, [2] PANIMALAR INSTITUTE OF
TECHNOLOGY, [3] PANIMALAR ENGINEERING COLLEGE.
[1]ashwinmurali@outlook.com, [2] iambhuvan@outlook.com, [3]varuncharavanan14@gmail.com.
ABSTRACT
For the past two decades there has been an upsurge in the
road accidents due to car crashes. Nearly 1.3 million
people die in car crashes each year, on average 3,287
deaths a day. Even though there is so much of
developments in the field of automobile there is no
sophisticated system for securing the vehicle as well as
its passengers during the crash. There are some existing
electronic systems for preventing the crashes but they are
not completely reliable so it is better to absorb the crash
impact than trying to prevent it. So in this project we are
introducing a crash absorption system which completely
absorbs the crash impact force when two cars collide.
Rubber attached bracket and torsion bar constitute the
crash absorption system. This system is controlled by
programmed microcontroller which makes this system
function able only at the time of accident. Ultrasound
sensors and infrared sensors assist in increasing the
efficiency of the system. Hence we propose that this
system can reduce the effects of crash and has the
potential to save human lives.
Keywords: ultrasound sensor, bracket,
microcontroller and crash absorption.
INTRODUCTION
Road accidents have been increasing at an enormous rate
since the development of vehicles. In the past three
decades car accidents have been responsible most of the
accidents. Car accidents are very much destructive, they
cause damage to car body resulting in huge loss at the
same time they can also claim human lives depending
upon the intensity of the accidents. Accidents are the
prime concern for most of the automobile companies.
Many systems have been developed which mainly
focuses on accident prevention. These systems are
automatically controlled through electronic systems. In
reality these systems are not completely effective in
averting accidents. Accident prevention systems can just
warn the driver or apply brakes automatically before a
crash which cannot stop a high speed approaching
vehicle. So it is better to absorb the impact of the crash
then trying to prevent it. So this paper targets the
concept of collision impact absorption aided by an
electronic system incorporating cloud computation. The
main idea is to develop a lightweight, extremely
effective energy absorption system for improving the
energy management effectiveness of the primary crush
zone of a vehicle. While protecting a vehicle's occupants
from injury in a crash is a challenge for every vehicle
manufacturer, in the case of a small, lightweight car , it is
a particular challenge, due in part to the limited ability of
small cars to absorb collision energy, and the relative
short crush distance which is a major factor in providing
a ride-down or deceleration distance for the vehicle
occupants. In a conventio33nal steel-bodied vehicle, the
body panels are shaped and reinforced to form crush or
crumple zones that are designed to absorb collision
energy while protecting the passenger compartment or
so-called occupant interior cage. Smaller, lighter weight
cars offer particular challenges to engineers to provide
adequate crash energy absorption. Efforts to improve
passenger compartment protection typically add weight
to the vehicle and thus adversely affect fuel economy.
LITRATURE REVIEW
Kenji Fujita invention objective was to provide an
automatic drive system to a car which can recognize the
surrounding and react in accordance to that of a path
ahead of the car, such as a camera, and a transmitter. On
ISBN-13: 978-1539045540
www.iirdem.org
Proceedings of ICEEM-2016-Chennai
©IIRDEM 201612

2. the basis of the driving situation of the car, which is
identified on the basis of conditions recognized by the
control system, a control scheduling means selects at
least one among multiple of control programs. Car
control is provide to braking system and a steering
system, automatically controlled with the most effective
control program to drive the car so as to avoid a possible
crash against an obstruction in the way ahead of the car
Jan Willem Vermeulen et al., invented a Part that can be
fixed to the front part of automobile, consists of a
supporting construction which is assembled from
various parts manufactured from different metal plate
material and provided with attachments for fixing the
guard to the vehicle, a plastic cover element is separately
covering the sides of each profile part facing away from
automobile, and the connecting members connect the
cover element to support the construction, and between
the profile parts of the supporting construction and the
cover element free space is present and the cover element
is deformable plastic
Bruce Leigh Kiehne designed a vehicle with an accident
prevention system. The vehicle has conventional foot
brake for halting the vehicle. The system includes a
sensor system for sensing an object behind the vehicle
that generates an object identification signal when it
senses an object within range behind the vehicle. The
sensor arrangement is inclusive of passive IR sensors or
reflected pulse sensors such as sonar or radar sensors on
the end. A controller creates an accident prevention
response signal on receiving the data that is object
recognition signal from the sensor system. A brake
applying mechanism is parallely coupled to the brake to
stop the vehicle when the controller generates a response
signal. Conveniently the system comes with an alarm
signal. A method to prevent accident whenever a vehicle
is reversing the problem of collision with a person is also
dealt with.
Hyoung Pyo Hong patented an accident prevention
apparatus for a car is disclosed, which is provided at a
front of a car to protect a hit pedestrian by deploying a
safety cover upon collision with the pedestrian. The
accident prevention apparatus comprises a sensing unit
which detects a collision impact, and a driving unit which
deploys the safety cover according to the operation of the
sensing unit. The sensing unit comprises a receiver and a
connection bar connecting the receiver to the driving
unit, while the driving unit comprises a bursting part
operated by the connection bar, and a deploying part
deploying the safety cover according to the operation of
the bursting part. Since the accident prevention apparatus
is built in a main body of a driving unit when not in use
and promptly deploys a safety cover upon a collision
accident in accordance with the car speed and efficiently
captures the hit pedestrian, safety of the collision victim
is greatly improved. Also, chain collision by following
cars and other sequential accidents can be prevented.
ROAD ACCIDENTS STATISTICS:
Nearly 1.3 million people die in road crashes each year,
on average 3,287 deaths a day. An additional 20-50
million are injured or disabled. More than half of all road
traffic deaths occur among young adults ages 15-44.
Road traffic crashes rank as the 9th leading cause of
death and account for 2.2% of all deaths globally. Road
crashes are the leading cause of death among young
people ages 15-29, and the second leading cause of death
worldwide among young people ages 5-14. Each year
nearly 400,000 people under 25 die on the world's roads,
on average over 1,000 a day. Over 90% of all road
fatalities occur in low and middle-income countries,
which have less than half of the world's vehicles. Road
crashes cost USD $518 billion globally, costing
individual countries from 1-2% of their annual GDP.
Road crashes cost low and middle-income countries USD
$65 billion annually, exceeding the total amount received
in developmental assistance. Unless action is taken, road
traffic injuries are predicted to become the fifth leading
cause of death by 2030.
ISBN-13: 978-1539045540
www.iirdem.org
Proceedings of ICEEM-2016-Chennai
©IIRDEM 201613

3. COMPONENTS:
ACCIDENT PREDICTION SYSTEM
Fig1: ULTRASOUND SENSOSR
Fig2: DB9 CABLE
The crash prediction system consists of ultrasound
sensors for measuring the distance between the driving
vehicle and the approaching vehicle. The ultrasound
sensors are placed on all the 4 sides of a car for getting a
complete 360 degree view of the surroundings. An OBD
is utilized for providing speed data. CAN BUS and DB9
cables are used for data transmission from OBD. A
microcontroller is placed near the OBD which collects all
the data, processes the information and decides whether
or not to activate the system.
CRASH ABSORPTION SYSTEM
Fig3 TORSION BAR
The crash absorption system consists of pneumatic
circuit consisting of a compressor, reservoir, FRL unit,
5/2 valve and a cylinder placed adjacent to the car
chassis. The compressor compresses atmospheric air and
then sends it to the reservoir. From the reservoir air
enters the cylinder through a solenoid controlled 5/2
valve. The functioning of the solenoid valve and its
actuation time is pre-programmed in the microcontroller.
FRL unit regulates the process and assist in proper
functioning of the pneumatic system. The cylinder is
attached to the chassis by an U-clamp. To the U-clamp
the cylinder is welded horizontally. The piston pushes
and pulls back a shock energy absorber. The shock
energy absorber is the main crash absorbing component
of the system. The shock energy absorber is made up of
RZ5 magnesium alloy as it is light in weight and has
good strength for withstanding impact loads. The shock
energy absorber contains torsion bar, which acts as the
shock absorbing component. In addition to the torsion
bar a thick layer of rubber is placed between the shock
energy absorber for damping the vibrations. Another
layer of rubber is placed on the curved portion of the
shock energy absorber where the first impact happens.
The shock energy absorber pivots on a shaft which is
attached to the car chassis. This RZ5 magnesium alloy
shaft also helps in holding the torsion bar firmly. Its
composition is zinc rare earth metals and zirconium.
DESIGN OF TORSION BAR
The Torsion bar was designed in catia V5 and analysed
in ANSYS Workbench V 15.0. Torsion bars of various
diameters were designed and analysed by trial and error
method. Since there are two torsion bars used in the
system the load gets divided into two. Considering a
maximum impact from a car approaching at 60km/hr
900KN-m moment was applied on the torsion bar. The
torsion bar was found to be safe for a diameter of 60mm
and the factor of safety was obtained as 1. Material that
was used for torsion bar is AISI 4140.
Mechanical properties of AISI 4140 for a section of
60mm are
Yield Strength= 770Mpa
Tensile Strength= 930Mpa
ISBN-13: 978-1539045540
www.iirdem.org
Proceedings of ICEEM-2016-Chennai
©IIRDEM 201614

4. Elongation=17%
Impact Izod= 90J
Hardness= 275 HB
Fig 4 Design of torsion bar with the fixed support
Fig 5 Moment is applied on the torsion bar
Fig 6 Total deformation
Fig 7 Equivalent Stress
Fig 8 Strain Energy
Fig 9 Safety Factor
SPECIFICATIAONS
Ultra sound sensor-Hc-sr04
Working voltage DC 5 v
Working current 15mA
Working frequency: 40 Hz
Max range 4 m
Min range 2 m
Measuring angle 15 degrees
Trigger input signal: 10 micro seconds TTL pulse
Echo output signal input TTL lever signal and range in
position
Dimensions 45*20*15
Hardware used - Intel Edison
Intel atom dual core
Processor 500 mhz
Ram 1Gb DDR3
Rom eMMC 4Gb flash
Bluetooth 4.0 Wifi
On-board diagnostics (OBD) is an device used for self
diagnostic and problem identification in an automobile.
WORKING:
ACCIDENT PREDICTION SYSTEM
On board diagnostic (OBD) is used to transmit the speed
of the vehicles to microcontroller. OBD is present in
almost every car to get access to the status of vehicle
subsystems. From the OBD various parameters can be
obtained , upto 16 data like speed, temperature etc. from
various sensors. In this system it works on cloud
principle. Every vehicles speed is sent to the cloud from
the OBD where it is shared to the other vehicles OBD.
The OBD gets the speed of every approaching vehicle
and transmits it to the microcontroller along with the own
vehicle speed. A CAN BUS is utilized to connect the
microcontroller and the OBD for effective data
ISBN-13: 978-1539045540
www.iirdem.org
Proceedings of ICEEM-2016-Chennai
©IIRDEM 201615

5. transmission between them. The data from CAN BUS is
transferred through a DB9 cable to the microcontroller.
Simultaneously the ultrasound sensor calculates the
distance between the approaching vehicle and the driving
vehicle to the microcontroller. Once the microcontroller
gets all three data, it substitutes’ it in the condition
programmed. When the condition gets satisfied the crash
absorption system gets activated. The microcontroller
supplies current to the pump from the battery.
BLOCK DIAGRAM
Fig 10: Block Diagram
CRASH ABSORPTION SYSTEM
The reservoir is filled by the compressor and it is
constantly checked for pressure loss by the
microcontroller. When the sensors sense crash, the
microcontroller activates the crash absorption system The
air from the reservoir enters the cylinder and inturn it
pushes the shock energy absorber. The shock energy
absorber rotates on a pivoting shaft and comes protruding
out of the car for a distance of 18cm. So that the first
impact of the colliding car is on the crash bar. The first
impact area is completely made up of thick rubber, which
absorbs most of the impact load. The shock energy
absorber contains high performance torsion bar for
absorbing the crash energy. So when a car hits the shock
energy absorber bar, it compresses due to the rotation of
torsion bar. Finally the rotation of torsion bar is damped
by another set of thick rubber which completely
eradicates the crash energy from reaching the car body.
The shock energy absorber looks as a car skirt until it
operates and comes into position once a crash is
predicted. In this way the car can be secured during a
crash and damage to body as well as the passengers can
be prevented with less damage on the shock energy
absorber.
DESIGN AND ANALYSIS
The design was done using catia V5. The assembly view
consists of the crash energy absorber and the pneumatic
circuit.
Fig11: ISOMETRIC VIEW 1
Fig12: ISOMETRIC VIEW 2
Fig13: ISOMETRIC VIEW 3
ISBN-13: 978-1539045540
www.iirdem.org
Proceedings of ICEEM-2016-Chennai
©IIRDEM 201616

6. Fig14: TOTAL DEFORMATION 1
Fig15: TOTAL DEFORMATION 2
CONCLUSION
Thus we have designed a crash safety system
which is especially for four wheeled vehicles.
This safety system will be very effective in
any road conditions. It has the potential to
minimise the effect of crashes and it can
prevent car body from getting damaged. Apart
from that it can protect the passengers even
during high speed head on collisions. It can be
installed in any cars. So we hope it has the
potential to save human lives.
REFERENCE:
[1] https://en.wikipedia.org/
[2] https://patents.google.com/ Bumper protecting
device for damping and absorbing impact in collision for
vehicle
[3] https://patents.google.com/ Device for new car
anticollision energy-absorbing
[4] DESIGN OF MACHINE ELEMENTS by
RS.KHURMI from S.CHAND PUBLICATIONS.
[5] DESIGN DATA: P.S.G DESIGN DATABOOK OF
ENGINEERS from kalaikathir atchagam..
[6] springipedia.com/material-springmaterials.asp
[7]www.engineersedge.com/spring_general.htm
ISBN-13: 978-1539045540
www.iirdem.org
Proceedings of ICEEM-2016-Chennai
©IIRDEM 201617