Objective: Composites may enable further weight reductions for plastic composite intensive vehicles. Among the challenges associated with greater adoption of composites in the automotive industry are the need for novel design procedures, the use of composites in impact applications and the greater variability during composite manufacture. Here, are method is presented to account for composite manufacturing variability in the design phase.
Methods: The method is based on measuring the variability in a part and the translation into a simulation. As an example a side-pole impact into a doorsill subassembly was chosen. The test data are used to validate numerical simulations models for the impact situation. The simulation is then used to study the sensitivity of the system with respect to manufacturing variability. A novel optimization was also used that decouples multiple manufacturing variations and allows identifying limits on acceptable variability levels.
Results: The experimental tests exhibit changes in mechanical performance due to the existence of manufacturing variations. The numerical simulation including these manufacturing variations shows reasonable agreement with the experimental data. The FE model was then used to vary the manufacturing variations and to identify allowable intervals within defined performance criteria.
Conclusion: The design methodology has significant benefits for automotive composite design and manufacturing since it may enhance the robustness of composite crash-structures, reduce part cost and eliminate excessive safety factors to account for unknown manufacturing variations.