This slide include various type of airbags used in automobiles, their types, advantages and etc.

1. Air Bags Used In
Automobiles
SUBMITTED BY : SAHIL DEV
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2. CONTENT
 Introduction
 Purpose
 Physics of airbag during collision
 Need of the airbag in connection with the safety benefits
 Design and construction of airbag system
 Types of airbag
 Functional characteristics required for airbags fabric
 Raw material and manufacturing method
 Finishing process
 Comparison of nylon and polyester airbag fabric
 Types of airbag fabric
 Development in airbag system
 Conclusion
 References
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3. INTRODUCTION
 An airbag is an automotive safety restrain system for an occupant as well
as passengers. The system consists of a flexible fabric envelope or cushion,
designed to inflate rapidly during an automobile collision.
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► A safety device used in the four
wheelers to avoid the Head and
Chest injuries from collision by
providing the cushion between
the occupants.

4. PURPOSE
 To protect occupants during a crash and provide protection to their bodies
when they strike interior objects such as the steering wheel or a window
 Protect the head and upper body from hitting to steering wheel compared
to seat belt alone. Airbag have reduced death by 28%, serious injury by
29% and hospitalization by 24%
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5. PHYSICS OF THE AIRBAG DURING
COLLISION
The Inertia Theory : If an object moving at a constant velocity continue at the
same velocity unless an external force acts upon them. This law, known as the
law of inertia, is demonstrated in the car collision.
Based on Newton’s law:
F = m ( -V/∆t )
Where,
F = Force on the body
m = Mass of the object (Body)
Vi = Velocity of the moving object (After collision it will decrease)
a = (V/∆t) = Acceleration (After collision it will decrease)
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6. CONTINUE…
The injury can be avoided by reducing the force on the body. This can be
done by two ways as :
 By increasing the time interval (∆t) over the force being applied
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7. CONTINUE…
 By spreading the force over large area of the body
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Distribution of force over body

8. NEED OF AIRBAGS IN CONNECTION
WITH THE SAFETY BENEFITS
 Reduction by 26% in moderate to serious injuries by airbags and seatbelts
together than only by seat belt.
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0
20
40
60
80
100
Airbad and belt Belt alone
Percent reduction in moderate to serious head injuries (Compared to
drivers using no restraining safety equipment)

9. DESIGN AND CONSTRUCTION OF
AIRBAG SYSTEM
 There are three parts to an airbag that accomplish this action
 Airbag itself
 Crash sensor
 Inflating system
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10. AIRBAG INFLATION SYSTEM
 The sensor sends the electric signal to burn the propellant kept here to
generate the gas
 Monitors the readiness of the airbag system
 A device that stores enough electrical energy to deploy the airbag if the
vehicle’s battery destroyed in it
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11. CHEMISTRY BEHIND AIRBAG
Mainly two types of gas are used :
 Nitrogen gas based airbags
NaN3 (S) ======> 2Na (S) + 3 N2 (G)
10 Na (S) + 2 KNO3 (S) ======> K2O (S) + 5Na2O (S) + N2 (G) ↑
SiO2 (S) + K2O (S) + Na2O (S) ======> K2SiO3 (S) + Na2SiO3 (S)
 Carbon dioxide gas based airbags
NaHCO3 (S) + CH3COOH (Aq) ======> CO2 (G) + CH3COONa (Aq) + H2O(L)
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12. OPERATION SEQUENCE OF AIRBAG
 Collision
 Sensing and inflation
 Fully deployed
 Deflation
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13. TYPES OF AIRBAG 13
Driver side airbag Passenger airbag Knee airbag

14. TYPES OF AIRBAG 14
Curtain airbag Side thorax airbag Door mounted side airbag

15. THE FUNDAMENTAL CHARACTERISTICS
REQUIRED BY THE AIRBAGS FABRIC
 High bursting strength
 Good fire retardancy
 Light weight
 Compact folding ability
 Low cost
 Reduced skin abrasion (Softness)
 High tear propagation resistance
 Resistance against ageing
 Defined dimension stability
 Air seal ability i.e. low air permeability
 Good coating adhesion
 Good fog resistance
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16. RAW MATERIAL AND MANUFACTURING
METHOD
Following multi-filament are used
 Nylon 6
 Nylon 6,6
 Polyester
 PA 46
PA 46 has higher melting point (285ºC) than Nylon 66 (260ºC) but cost of PA 46 is higher
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Fiber Yarn Fabric Coating
Cut/SewAirbag
Module
Assembly
Silicone
others

17. FINISHING PROCESS
 Cutting the fabric in required shape by laser
 Sewing by nylon-66, polyester and Kevlar aramid yarns
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Desizing Calendaring Heat set Inspection
CuttingSewingFolding

18. NYLON V/S POLYESTER
Properties Nylon 6,6 Polyester
Specific heat capacity (kJ/kg/K) 1.67 1.3
Melting Point (ºC) 260 258
Softening Point (ºC) 220 220
Energy to melt (kJ/kg) 589 427
Density (kg/m3) 1140 1390
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19. CONTINUE…
 Fabric coverage is reduced for the
polyester fabric that gives less thermal
protection to the passenger.
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20. CONTINUE…
 Low heat capacity of polyester at 400ºC temp for 2 second
 Poor ageing performance of polyester in hydraulic degradation behavior
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21. CONSTRUCTION DETAILS FOR AIR
BAG FABRICS
Driver side Passenger Side
25 x 25 plain weave
840 D nylon 6,6
Scoured, heat set, coated
25 x 25 rip stop
840 D nylon 6,6
Scoured, heat set
46 x 46 plain weave
420 D nylon 6,6
scoured, heat set, coated
41 x 41 plain weave
630 D nylon 6,6
Scoured, heat set
49 x 49 plain weave
420 D nylon 6,6
Scoured, heat set
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Typical characteristics of driver and passenger side fabrics used in airbags
(Courtesy of AlliedSignal)

22. CONSTRUCTION DETAILS FOR AIR
BAG FABRICS
Parameters Uncoated Coated
(Epi x Epi) 25 x 25 25 x 25
Thickness 0.013 0.107
Weight (oz/ sq. yd) 5.69 8.30
Tensile strength
Warp
Filling
533
549
450
478
Elongation
Warp
Filling
33.6
35.3
28
38
Tongue tear
Warp
Filling
199.4
192.5
85
83
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Typical properties of 840 Denier, nylon 6,6 Airbag Fabric (Courtesy of AlliedSignal)

23. TYPES OF AIRBAG FABRICS
 Coated airbag fabrics
 Uncoated airbag fabric
 Needle punched airbag fabrics
 Woven and nonwoven combined airbag fabric
 One sided laminated woven and nonwoven combined airbag
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24. COATED AIRBAG FABRIC
Coating substances elastomeric material as
 Neoprene
 Silicone
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25. ADVANTAGE OF SILICON OVER
NEOPRENE
 Needed in half amount so lighter, pliable, less thicker fabric
 More chemically competitive and cheap with nylon
 Better heat resistance and stability
 Prevents burn through (Pinholes) so maintains air permeability of the
fabric
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26. THE PROBLEMS WITH COATED
WOVEN FABRIC AIRBAG
 Formation of bubbles during coating
 Breakup of film due to non integration of film and fabric
 Injury to face skin
 Irregularities during coating
 Recyclability of the airbag becomes difficult
 Fabric becomes stiffer
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27. UNCOATED AIRBAG FABRIC
 Woven in a manner that creates a product possessing low permeability
 Provide calendaring treatment to reduce permeability
 Extrusion coated with a thermoplastic material to make them air
impermeable
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28. ONE SIDED LAMINATED WOVEN AND
NONWOVEN COMBINED AIRBAG
 Offer air seal ability and fire retardancy while being lightweight
 Heavy weight per unit area
 Reliability of the air bag is poor, are not solved
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29. NEW DEVELOPMENT IN AIRBAG
SYSTEM
 Lower Leg Airbag : Autoliv’s Inflatable Carpet protects the car occupant’s
feet, ankles and lower legs in frontal crashes by removing the feet from the
intruding foot well of the vehicle
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30. CONTINUE…
 Radial Deployment System (RDS) : Airbag (Umbrella RDS) coves the
steering wheel-saves the short person
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31. CONCLUSION
 Airbags is one of the inevitable components in car and vehicles to
safeguard drivers and passengers as per present applications. SO selection
of material is key feature for airbag manufacturing
 Airbags made from nylon 6,6 are more popular due to their inherent
properties of strength, energy absorption, thermal resistance and
environmental stability
 Textile and automobile industry may provide effective safety to the drives
and passengers during driving time
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32. REFERENCES
1. Aravin P. Periyasamy & Moin Khan, "Theory Behind In Air Bags Application in Automobiles”.
2. Khan. M. S, project done by DKTE students, online launched on Textile review, “Air bags for automobiles.
3. Kunal Singha, “Strategies for in Automobile: Strategies for Using Automotive Textiles-Manufacturing Techniques
and Applications”, Journal of Safety Engineering 2012, 1(1): 7-16 9. Indian textile research journal, “Airbags &
airbag textiles”.
4. Dupont , Sun. J, Barnes J. A, Airbag End-Use Technology, “Material selection for Air-bags” , pp 1-8.
5. Tasnim N. Shaikh, Satyajeet Chaudhari and Hiren Rasania ,“Air Bag: A Safety Restraint System of an Automobile”,
Department of Textile Engineering, Faculty of Technology & Engineering, The Maharaja Sayajirao University of
Baroda, Vadodara, Gujarat, Indi
6. S.Adanur, “Wellington Sears Handbook of Industrial Textiles”, Technomic, Switzerland, Ed. 1st edition, 1995, 500-5
Aravin P. Periyasamy & Moin Khan , “Theory Behind In Air Bags Application in Automobiles”.
7. Walter Fung And Mike Hardcastle , ‟Textiles in automotive engineering Woodhead” Publishing Limited.
8. Mukopadayay, S.K., and Partridge, J.F., “Automotive Textiles”, 1997, Textile progress, 29(12), 29-34.
9. Prof. P.A. Khatwani, Mr. S.S. Yardi NCUTE- programme on “Technical textile”.
10. http://textilepapers.tripod.com/airbags.htm
11. http://www.autoevolution.com/news/how-airbags-work-6362.html
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33. THANK YOU
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