In order to consider manufacturing condition, recently 6-sigma concept is introduced to the design optimization process. Let’s consider 6-sigma constraints in the robust design formulation shown in the figure. Figure 1 shows 6-sigma inequality constraints. This represents that the optimal design has 0.0000001% violation possibility of inequality constraints within the variations of random design variables and noise factors. RecurDyn/AutoDesign provides a robust design optimization with 6-sigma constraints.
Figure 1 typical formulation of 6-sigma inequality constraint