Computer aided process planning for sheet metal bending: A state of the art

Purpose of this paper is to offer the reader an overview of recently performed and ongoing research related to process planning for sheet metal bending, thus providing a starting point for further exploration of this field. The scope of this review paper is limited to sheet metal bending as performed on numerically controlled press brakes, with special focus on air bending. Automatic process planning requires a good understanding of the material behaviour under process conditions. Therefore some space has been reserved for an overview of bend modelling efforts and, directly linked to this, in-process measurement and adaptive control methods. Part representation and feature classification methods for bent sheet metal parts are also discussed. Sections are dedicated to the core problems of fully automated process planning in sheet metal bending: bend sequencing, collision detection, tolerance verification and tool selection. The state-of-the-art review is completed with an overview of ergonomic analysis methods for process plan evaluation.