EXPLORATORY STUDY ON THE SUITABILITY OF AN AIRBAG FOR AN INDIAN MOTORCYCLE USING FINITE ELEMENT COMPUTER SIMULATIONS OF RIGID WALL BARRIER TESTS

摘要

Airbag's feasibility for the large touring motorcycles in mitigating severe injuries or avoiding fatality to the rider in a fatal crash has been established. However, airbag's suitability is not yet established for the smaller motorcycles which are used in India and other South Asian Countries; as means of transport rather than amateur riding. The current study is a first of its kind to address an issue of safety of Indian motorcyclists in a fatal crash by airbag. Study was aimed at finding appropriate: triggering time of airbag inflation process, backing surface, location and orientation of airbag module, and size of the airbag; in restraining effectively and absorbing maximum kinetic energy of the rider in the primary fatal impact with the rigid wall barrier. The study undertaken was the great challenge in the developing country such as India where there is no facility to conduct an actual barrier test on a motorcycle with a dummy installed with all the instrumentations. It is also extremely difficult to get the data and design details of every object used in the actual crash tests conducted elsewhere in the world. As per ISO 13232 standards (6), rigid wall barrier test simulations of motorcycle with airbag and rider were performed to arrive onto any conclusions. A Finite Element (FE) model of a representative Indian motorcycle of 100cc was developed which behaved realistically in the barrier test simulation. The developed realistic models of folded airbag, MATD neck and helmet were used. MATD neck was integrated into the available ATD model. All the FE models of the components were integrated to have a complete system to conduct barrier test simulations in 90 degree and 45 degree angles of impact. Simulations were performed using nonlinear FE software Pamcrash. It was found that the sensor time should be lowest possible for triggering airbag inflation process due to smaller space available with the motorcycle. A need of a backing surface was felt for properly restraining the rider by airbag. Different alternate arrangements were studied to find out proper location and orientation of the airbag module in the motorcycle. Effect of different sizes of airbag was studied in absorbing the kinetic energy of the rider during the crash. The study found out appropriate triggering time, backing surface, location and orientation of airbag module and airbag size in effectively restraining and absorbing maximum kinetic energy of the rider in the fatal crash. The scope of the study was the primary impact, where the rider's head impacts into the rigid wall barrier in the fatal crash. The study has not considered following: a scenario of fall of a rider on the ground, angular impact sensitivity analysis, presence of a pillion rider, and full scale crash tests mentioned in ISO 13232 standards. At the end of this study it can be said that the broader research question of suitability of the airbag in Indian motorcycle in mitigating injuries to the rider in the fatal crash is answered in affirmative.