This presentation was made at the NAFEMS Americas Seminar - Confidence in Engineering Simulation: The Next 10 Years of CAE in Mexico.

What is the future for engineering analysis and simulation in Mexico? Discover innovative engineering simulation processes and tools which are helping companies in Mexico improve production capabilities. Engage with domain experts, industry leaders, and peers in a focused, comprehensive one-day event that covers topics on engineering analysis, simulation, and systems modeling and simulation that every engineer in Mexico should know.

Resource Abstract

At an advanced stage of the development process where the vehicle was mature and already met the required performance, the manufacturing team informed that the capacity of specific welding stations was exceeded in one of the plants where the vehicle was going to be manufactured. Leading to decide between investing to increase the plant capacity or reducing the amount of welds in the design to fit current capacity. The first option implied a cost that must be justified and in the second there was a risk of impacting the performance.



To support the decision, the team carried out a study to better understand the impact on performance due to the reduction of welds. Since the original design included several thousands of welds and the response time was short, the design space had to be bounded. Considering conditions like commonality, supplier welds and safety, the subspace to study was about 600 spot welds, each considered as a discrete and binary variable, presence or absence.



Given the fact the amount of combinations was high and two load cases needed to be evaluated per combination, the subspace did not qualify for physical testing and was not manageable for one analyst. Therefore, it was decided to use virtual validation (FEA) along with automation and optimization tools (TCL for Hyperworks and HEEDS) which would help to obtain the optimal solution in the trade off curves of performance vs number of spots.



After 600 iterations, the result was that 18% of spots could be eliminated with a marginal impact of 0.6% and 1.6% in torsion stiffness and diagonal distortion at liftgate opening respectively. This provided the data that supported the decision to not to invest in increasing the capacity while staying within acceptable level of performance.