An interactive computer-aided design system has been developed for the blank layout of progressive press dies. The geometry is described as wire frame models, consisting of line segments and circular arcs; widely used for two dimensional press product shapes. The geometry definition part has modules for data base and display. The geometric data are organized in a hierarchical structure for points, lines, circular arcs, signed-closed-figures and patterns. A product is defined by patterns. APT-like commands are made to define these geometric elements.
Maximum material utilization has been the goal chosen by the blank layout, which includes multi-row layout. This part has various computational modules for distances and areas, to best satisfy desirable distance-constraints. Flexibility is given for maximum use of the user's knowledge, while minimizing the amount of input for unexperienced users by default options.
The program written in FORTRAN has been designed to be independent of software and hardware as much as possible. Considerations are also given to obtain faster response by tailoring the subroutines to perform their special purpose. For future extension to other parts of press die design with more complex geometries, the program has been made in modular structure.
