Feature recognition methodology for shearing operations for sheet metal components

In this paper, a feature recognition methodology has been proposed for recognizing shearing operations for 2D sheet metal components created by a wireframe model. The methodology initially processes geometric data for identifying different entity groups. The entity groups are classified into a raw material feature set, a boundary feature set and an inside feature set. Inside feature set elements belonging to boundary feature set elements are identified uniquely. Components (i.e. elements of the boundary feature set along with its elements of the inside feature set) are arranged lexicographically. Manufacturing features are identified based on the proposed classification system for shearing operations and using different feature sets. The above methodology, along with its principles, is illustrated with examples. This is implemented in the C language on a PC-AT, and the geometric data are obtained from AutoCad's DXF output file.