Reducing variability of a set of structures assembled from uncertain substructures

In this paper, the effect of component variability (due for instance to dimensional tolerances) on the dynamics of an assembled structure is modeled using procedures derived from Design of Experiments (DOE). Central composite design is used to fit a regression model of the effect of uncertainties and of their interactions. The regression model is verified by comparing the output of the fitted model with results of the physical model. The fitted model is then used instead of the physical model to evaluate the dynamic behaviour of the assembled structure. A reduced fitted model is defined by taking into account only the contribution of most significant uncertainties. By using the reduced fitted model, selective assembly procedures are devised in order to reduce the dynamic variability of a set of assembled structures.