International standard provides guidelines for product control and inspection (ISO-GPS or ASME-GD&T); however, the integration of tolerance standard into nominal sized CAD models is not yet achieved. Current, Computer Aided Tolerancing (CAT) tools mainly capable to model orientation and position tolerance specifications, whereas part shape errors are omitted. This paper presents an innovative physics-driven simulation framework to model shape errors of compliant sheet metal parts at early design stage.
The modelling framework consists of three important stages: (i) initial shape error prediction using physic-based simulation, such as, stamping process simulation; (ii) individual orthogonal shape error modes/patterns identification based on decomposition techniques, such as, Geometric Modal Analysis (GMA); and, (iii) simulation of shape error variation classes by assigning distribution to each orthogonal shape error modes. The proposed approach enables to generate shape errors at early design stage of assembly process which can be utilized to optimize the assembly process, including fixture design and joining process parameters. An industrial automotive component illustrates the proposed methodology.