REVERSE ENGINEERING OF EXPERIMENTAL TESTS RESULTS OF BALLISTIC IMPACT FOR THE VALIDATION OF FINITE ELEMENT SIMULATIONS

In this paper the set up and the carrying out of experimental ballistic tests on a tail rotor transmission shafts for helicopter, which are impacted by a 7.62 NATO projectile, are presented. After the tests, a 3D acquisition of the impacted area on each shaft has been performed in order to acquire exactly the shape of the damage. The acquisition has been carried out with a 3D range camera. The experimental activities have been compared with the results of a numerical simulation of the impact, which has been computed with an explicit finite element code. The direct comparison has been done by superimposing the two meshes (from FE analysis and from 3D acquisition). This method has proved to be effective for identifying analogies and differences and for giving the possibility to promote a “quantitative” discussion with the aim of improving the accuracy of the numerical models and simulation conditions. The adoption of the Reverse Engineering practice has proved to be a powerful method for integrating and comparing the simulation data with real data, and give suggestions to further analysis.