Integrated feature-based modelling and process planning of bending operations in progressive die design

This paper describes an integrated modelling and process claiming system developed for planning bending operations of progressive dies. The approach is feature- and rule-based. The paper presents a detailed description of the bending structure and its associated bending operations in the progressive die context. The geometrical bend mapping function for feature elements within individual bends, and the transformation matrix for connected sub-bends, are examined and formulated. The bend features of the pan as well as their configuration and editing interfaces are defined. The paper also explains the algorithm used for determining the strip layout angle, and width and pitch. The system introduces, for the first time, a newly tabulated interface, which can satisfactorily represent the stations, operations, and their inter-relations for process planning. Configurable case-based reasoning algorithms for automatic operation planning are explored. The system was developed using C++ and ObjectARX of AutoCAD.