Thin -Walled Impact Energy Absorber Optimization in Dynamic Loading using Design Of Experiment Approach

In the present paper the optimization process of a thin-walled collapsible shock absorber geometry is performed using the well-known design of experiments method. The optimizing target parameters are the maximum energy absorption and the low impact shock. A number of four geometrical control parameters have been chosen in two different levels making a totally 16 different geometries. The collapse behavior of the absorbent geometries then has been simulated using a full 3D shell element LS-Dyna numerical model with an elastic-plastic material behavior and some main absorbing characteristics extracted. The collapse behavior of the geometries is simulated under axial impact of a traveling mass with a presumed kinetic energy. A comparison between the different geometries can be performed to obtain the effectiveness of the control parameters and decide about the most effective ones. It has been shown that while the thickness of the crushable structure is an important factor, an increase in the radius of curvature at the end of the presumed geometry is the most effective parameter in absorber efficiency. A study also is performed to validate the numerical simulation process with conical absorber geometry under axial quasi-static loading. The comparison exhibited a very good agreement between the numerical finite element results and the data acquired from the experimental test that showed the validity of the simulation procedure.