FATIGUE ANALYSIS FOR A STEERING KNUCKLE OF A BAJA SAE VEHICLE

Resumo

Fatigue in automotive components is of great interest for both automakers and consumers. Due to high
costs and time involved in experiments and tests of these vehicles, engineers often resort to analytical and
computational models during the design project phase. This work presents the fatigue analysis and expected
lifetime calculus for a steering knuckle used in an offroad BAJA vehicle. Different models were tested to choose
one which could most accurately represent known vehicle behavior, as experimentally verified by the Tchê Baja
team. Using loads obtained through a ride simulation in MSC Adams/Car, critical fatigue points were
determined for the component analysed. Cycle-counting was done through the rainflow algorithm, and correction
for mean stresses through the FKM directive and Goodman methods. The results show the differences in loads in
both critical points, as well as differences in the mean stress correction methods.