Automation of wheeled vehicles load bearing frames finite-element models loading procedure by using inertia relief method and vehicle multi-body dynamics model

The paper presents a technique for strain-stress calculation using finite element analysis for wheeled vehicle's load bearing frames with the use of loads, obtained from full vehicle multi body dynamics models (MBD models). In this technique, boundary conditions need not to be defined, as the inertia relief method used. Frame and suspension parts are imposed in MBD model as flexible bodies to increase accuracy of loads calculations. The presented method is capable to automatize loading procedure of finite-element models, thus decreasing computational costs and results processing costs while analyzing numerous load cases. As an example, strength analysis of 6x6 articulated vehicle frame is presented. Proposed method compared to "classic" finite-element frame modelling technique, which use conventional loads formulation and fixed boundary conditions. In load case "standing on ground", calculation results with the use of two methods demonstrate high convergence in zones, located far from suspension and frame mounting joints. For load case "hanging of second axis" results are significantly different, due to ability of MBD-model to capture behavior of suspension links, and calculate true vehicle frame movement in space in particular load case. Loading procedure of frame finite element model is automated, using script, which transfer loads from MDB-model.