Behaviour of an impact attenuator for formula SAE car under dynamic loading

A Formula SAE car must have structural devices that able to absorb most of the kinetic energy by means of progressive crushing therefore minimizing the forces and decelerations transferred to the occupant during frontal collisions. This paper presents the prediction of dynamic behaviour of an impact attenuator for a Formula SAE car under frontal impact conditions by using numerical and experimental approaches. The impact attenuator construction is a combination of sandwich panels and aluminium inner sheets. Firstly, the analysis of sandwich structures is carried out to better understand their behaviour and model them properly in the numerical simulation using LS-DYNA. In order to obtain the best configuration for the impact attenuator in terms of maximum absorbed energy, minimum deceleration and weight saving, its length and the number of inner sheets are optimised. Finally, a crash-test is performed on the impact attenuator to compare the experimental results with the numerical ones. The results obtained show that the impact attenuator is able to absorb the total impact energy with progressive and plastic deformation to contain the average deceleration as below 20 g. © 2010. MechAero Foundation for Technical Research & Education Excellence.