XU-RSM: Diffuse response surface model for reliability-based design optimization

We focus on a new response surface methodology (XU-RSM) adapted to RBDO, based on Diffuse Approximation. This method uses simultaneously the points in the space of probabilistic variables (U-space) and the points in the space of physical variables (X-space). The two grids form a "virtual design of experiments" and are progressively explored in order to minimize the number of the "exact" function evaluations. A variant of the first order reliability method FORM is chosen to calculate the safety index. A case study is investigated for the numerical control (NC) machining operations of ultrahigh strength steel. We show how the proposed method can decrease the amount of function calculations and reduce the computing time.