Paper Title
Development Of Simple Inflation Method For Deployment Of Airbags During Crash Testing And Parametric Studies

The purpose of airbags is to inflate and provide the cushion between the occupants and the vehicle’s interior during the event of crash by venting gas through vent hole provided in the airbag by bursting vent. This project work is carried out at National Aerospace Laboratories (NAL), Bangalore in Structural Technologies Division (STTD), Impact and Crashworthiness Research Facility (ICRF). The parameters considered for the studies are vent diameter, vent layer, voltage, particle size of chemicals and different types of igniters. Finally to demonstrate the developed inflation system in drop tower tests and hence further this system can be used during impact and crash testing experiments. In the preliminary study the characterization of the airbag fabric and vent material is carried out in UTM and by conducting uniaxial tensile tests in different directions for airbag fabric material (warp, weft and 00/450 directions) according to ASTM standards and for the vent material also uniaxial tensile tests were carried out according to the ASTM standards. An inflator is designed and fabricated for the airbag, which serves as a combustion chamber where in the chemical reaction occurs and gas is generated which inflates the airbag. The chemicals selected and used for inflation of the airbag in the present study are Sodium Azide (NaN3), Potassium Nitrate (KnO3) and Silicon Dioxide (SiO2). These chemicals are mixed and grinded manually. The particle size analysis is also done to check the reduction of particle size after grinding and study is carried out how the chemicals with varying grinding time as chemical particle size influences the rate of chemical reaction. The airbag inflation tests were carried out for airbags with two different shapes (spherical and cylindrical) airbags. The airbag inflation process is captured using high speed camera and pressure data during the process is acquired using Prosig 8020 Data acquisition system. The pressure data acquired is analyzed using Dats software. Using high speed image acquired velocity of the airbag deployment is measured using Image analysis software and velocity of airbag inflation is measured by image pro analysis software. Keywords— Selection of Airbag and Vent Material, Inflator, Chemicals, Airbag Inflation Tests.