STRUCTURAL ANALYSIS FOR AUTOMOTIVE A-PILLAR
Main article
Abstract
Car body design in view of structural strength and light weighting is a challenging task due to all the performance targets that must be satisfied such as vehicle safety and ride quality. An increasing pressure on vehicle manufacturers internationally and also several countries are mandating to reduce vehicle emissions. Thus, light weight strengthening solutions are required to increase roof strengths while minimising structural mass. In this paper, material replacement along with multidisciplinary design optimisation strategy is proposed to develop a lightweight A-Pillar vehicle structure that satisfies the crashworthiness criteria while minimising weight. Through finite element simulations, a Federal Motor Vehicle Safety Standard (FMVSS 216), Roof Crush Resistance test and by the Insurance Institute for Highway Safety (IIHS) was conducted at the A-Pillar model structure. All the tests set up, simulation test constraints and procedure will be based on the standard. Then all the models will be rated, using the specific strength or strength to weight ratio calculations to determine the best model among all the model that had been tested. The wall thicknesses of two parts are which is inner and outer layer of A-Pillar were considered as the design variables. The benefits of the new proposed material (mild steel, aluminium and high strength steel) include reduced mass and hence more efficiency. All the three materials had passed the FMVSS 216 test requirement as the total deformation was not more than 127mm under a force of 1.5 times the weight of vehicle,12.21 kN, was applied so that the test device moves in a downward direction perpendicular to the lower surface of the test device at a rate of not more than 13mm per second. Total deformation for mild steel (MATS 100039MAT2_16800) get the highest value and Aluminium (A6060) gets the lowest value under the FMVSS216 test. This shows that Aluminium (A6060) have higher energy absorption compared with the existing material. The improved A-Pillar with the new proposed material was able to secure a substantial margin of the survival zone as well as to meet the requirement specified by standard.
