Generating and veryifying die shape data for making automobile body parts

摘要

A method of generating shape data with a CAD system 10 to form a hemmed edge (46 Figure 2C) to be added to a design surface for a designed product, based on production technique requirements data 14 of the product, comprises the steps of: setting up rib calculation points for forming the hemmed edge on a peripheral edge of the design surface; setting up a hypothetical surface (52 Figure 6) on the peripheral edge, based on the production technique requirements data; determining arcs (50) in contact with the design surface and said hypothetical surface as rib data at the rib calculation points; and generating shape data to form said hemmed edge from the rib data.