Durability Analysis of a Harvesting Vehicle using Matlab and Ansys

The present paper describes an approach to predict fatigue damage of a mechanical system applying modal super-positioning. Initially a dynamic FEM beam model including a nonlinear wheel contact model has been developed for the harvesting vehicle structure. A load history is generated for a specific joint in the vehicle. From the influence matrix for the particular joint fatigue life is determined. For the full 3D solid FE model, modal super-positioning is introduced in order to reduce the computational costs. From modal analysis a limited number of mode shapes can be obtained and full deformation state is determined by modal super-positioning. The developed nonlinear wheel contact model and the modal system are coupled through a 3D beam element. The obtained fatigue life agrees well compared to actual observations and tests performed on a prototype.