Crashworthiness of a vehicle for rollover impact protection using IMPAXX and aluminum foam materials

Abstract

Rollover crash events frequency accounts for only 3% among all types of accidents, but in terms of fatality rate, it accounts for 33% of fatalities in automobile crash accident events. Rollover events are complex and unpredictable, making them quite difficult to design a standard testing procedures. The angle of contact with the ground, the side coming into contact, height of fall, speed of vehicle, cause for rollover, etc., are all parameters and factors which could affect rollover crash responses. Presently the standard testing procedure for rollover is a quasi-static roof crush test procedure. This study details the development, analysis and computational modelling and simulation of the performance of an IMPAXX and aluminum foam and their potential as an energy absorbing material to improve the roof strength of a vehicle. First the IMPAXX foam and Aluminum foam are modelled using the LS-DYNA code, and their performances are evaluated using a drop tower test and a free motion headform test methods. Next, the IMPAXX foam and Aluminum foam are modelled for insertion in the roof A-pillar of a typical sports utility vehicle (Toyota Rav4). Quasi-static roof crush computational tests, per two different standards FMVSS 216 and IIHS are conducted on the vehicle and solved using the LS-DYNA for vehicles with and without the IMPAXX and aluminum foam. The results are analyzed and compared to quantify the effectiveness of the IMPAXX foam and aluminum foam as energy absorbing materials for rollover crashworthiness responses of vehicle and its occupant protection.