SAFETY AIRBAGS IN CARS

GUIDED BY: PRESENTED BY:ANOOP KUMAR.G NOUBIN PAPPACHANLECTURER S7MB

DEPT. OF MECHANICAL ENGG. 105

NSS COLLEGE OF ENG.PALAKKAD

CONTENTS

• 1 INTRODUCTION• 2 BASIS OF AIR BAGS•3 DEVELOPMENTS OF AIR BAGS•4 CONSTRUCTION OF AIR BAGS• 5 WORKING• 6 MODERN TYPES• 7 FUTURE• 8 AIR BAG DEPLOYMENT• 9 AIR BAG CHECKS• 10 DISARMING AIR BAGS• 11 CONCLUSION

INTRODUCTION

Until recently seat belts provided the soleform of passive restraint in cars.

Slowly talks arose about their safety. Airbags have been under development formany years.

Statistics reveal that airbags reduce the riskof casualty in a DFC by 30%.

Airbags are the subject of seriousgovernments industry research and tests.

Newton’s second law of motion.

If objects aren’t restrained they willcontinue moving at the speed of the

moving car even if the car is stopped bya collision.

All airbags need to do is to slow downpassengers speed.

DEVELOPMENT

WORLD WAR-2 :saw the first patent on aninflatable crash landing device for airplanes.

1980:first commercial airbags appeared inautomobiles.

Ever since 1988 it became a binding.

Efforts to adapt the airbag was stranded dueto prohibitive prices and technical hurdles.

MAIN PARTS OF AN AIRBAG

Bag

Sensor

Inflation system

BAGS

Is made up of a thin nylon fabric, which isfolded into the steering wheel or dashboard orthe seat or door. The powdery substance released ( regularcornstarch or talcum powder) is used to keepthe bags lubricated while they’re in storage.

SENSOR

A device that tells the bag to inflate.It works with the control module to

discriminate between crash and non- crashevents.

INFLATION SYSTEM

NaN3+KNO3=large amts. of NITROGENGAS.

Hot Blasts of the nitrogen inflate the airbag from its storage site up to

322Kmph.

CONSTRUCTION OF AIR BAGS

Airbag are assemblies consisting of theairbag (made of Nylon), inflatormodules and sensor housing, electricalconnectors (Clock spring), airbag

retainer and the cover.

Inflator assembly

Control module activates airbagassembly- electric current is sent to the

detonator-ignition of sodium azidepallets-evolves nitrogen gas.

working

air bags are designed to inflate in frontal impactsin which the car strikes about 16 km/hr

After collision senors sents an electric current toignitor system Electric current heats the filament which ignatesthe capsule which in turn ignites the gasgenerating pallets The gas expands quickly and inflation of air bagsthere by takesplace,which break through a plasticcover in the steering wheel

Time take sec.

DRIVERS SIDE AIRBAG

Modern types airbags

Curtain airbags Developed by mercedes and volvo

Inflate infront of windows to providepassengers better head and neck

protection

More efficient at tipping and side impacts

Reduce HIC by 80%

Head throax bag Developed by ford and renault High protection to head

ITS Developed by BMW.

Worlds first airbag for head protection

Future of airbags

Smart systems Includes weight sensors

Determine type occupant in seat.ie.childor adult.

Infrared occupant Detect the distance of passenger fromairbags

Capacitive reflective occupantsensing

Identify distance passenger from dash board Discriminate between human occupant and

inanimate objects

Update sensor Deploys seatbelt pretensioners faster to getbenefit of airbags

Centralised electronic controlunit

New sensor technology through software

Air bag deployment

Airbag inflation

Depicits contact with airbag Coming to rest in seat and deflation ofairbag

All these take in 30 milliseconds

Airbags checks

When we turn key look at the dash tofind airbag light for 7-10 sec.&then go

out Problems occur when

1. light does not come on

2. if light does not go off after period3. if light comes during driving

Disarming airbags

Disconnect battery Wait 30sec.

Remove airbag fuse

Drop sound insulator panel Disconnect the circuits Thus the bag is disarmed

Keep the bag below 130degree celsius

CONCLUSIONS

Air bags are of greater importance intodays vehicles siince safety of human

life is of prior importance So far safe riding and for saving theprecious life the safety bags must be

implemented Let’s hope every automobile

manufacturer implements the same