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A common occurrence in computer aided design is the need to make changes to an existing CAD model to compensate for shape changes which occur during a manufacturing process. For instance, finite element analysis of die forming or die tryout results may indicate that a stamped panel springs back after the press line operation so that the final shape is different from nominal shape. Springback may be corrected by redesigning the die face so that the stamped panel springs back to the nominal shape. When done manually, this redesign process is often time consuming and expensive. This article presents a computer program, FESHAPE, that reshapes the CAD or finite element mesh models automatically. The method is based on the technique of volume morphing pioneered by Sederberg and Parry [Sederberg 1986] and refined in [Sarraga 2004]. Volume morphing reshapes regions of surfaces or meshes by reshaping volumes containing those regions.

Two types of approaches for material definitions and methods for worst case scenarios are explored. The first is from the material specification supplied by the OEM or the alloy producer for the material, which has basic material properties and no specific FLC. The potential exists that any material within the specification can be delivered to the stamping plants. The second is if the material is to be supplied within a narrowed band of material specification with a known FLC. For both cases, there is considerable pressure from product design to use the most formable material possible. However, if a material is delivered outside the FEA testing limits, the results can be catastrophic. A specification is proposed to take advantage of the formability capability to enhance product performance while minimizing stamping plant risk.