A blank shape determining method includes: a process of making a forming analysis of forming a reference blank into a reference formed product and a acquiring sheet thickness distribution and a plastic strain distribution; a process of acquiring a forming failure evaluation index for the reference blank; a process of estimating a region, which includes an end edge portion at which the forming failure evaluation index exceeds a predetermined threshold, within the reference blank as a forming failure region; a process of generating a plurality of corrected blanks; a process of making a forming analysis of forming the corrected blanks into corrected formed products and acquiring a sheet thickness distribution and a plastic strain distribution; a process of acquiring the forming failure evaluation index for the corrected formed product; and a process of determining a shape of the corrected blank having a smallest maximum value of the forming failure evaluation index as a shape of a blank provided for press forming.

This disclosure relates to systems and methods for automatically detecting three-dimensional shaping in a three-dimensional model of a sheet-metal part. Therein, data of a three-dimensional model of the sheet-metal part, which extends in a plane spanned by a first direction and a second direction, is detected, wherein the sheet-metal part comprises a bulge in a third direction which is different from the first and the second directions. Then, a horizontal cut is made through the bulge, as well as a vertical cut perpendicular to the plane spanned by the directions, so that closed cross-sectional contours of the bulge are formed. After a transformation, e.g., a Fourier transformation, of the cross-sectional contours, a tool that produces the bulge can be allocated to the Fourier coefficients.

A blank shape determining method includes: a process of making a forming analysis of forming a reference blank into a reference formed product and a acquiring sheet thickness distribution and a plastic strain distribution; a process of acquiring a forming failure evaluation index for the reference blank; a process of estimating a region, which includes an end edge portion at which the forming failure evaluation index exceeds a predetermined threshold, within the reference blank as a forming failure region; a process of generating a plurality of corrected blanks; a process of making a forming analysis of forming the corrected blanks into corrected formed products and acquiring a sheet thickness distribution and a plastic strain distribution; a process of acquiring the forming failure evaluation index for the corrected formed product; and a process of determining a shape of the corrected blank having a smallest maximum value of the forming failure evaluation index as a shape of a blank provided for press forming.