Algorithms for Design Feature Data Extraction From DXF Files

Feature recognition is the key linking element between CAD and CAPP. Different CAD/geometric modeling packages store the design related information in their own databases. Structures of these databases are different from each other. Automatic Feature Recognition (AFR) is the process of extracting such feature data for use in the other stages of product life cycle viz., process planning, CNC code generation and inspection etc. This paper presents different algorithms to extract the design data stored in the form of Data Exchange Format (DXF) files and to store such data in an orderly form.. A software program is developed in ‘C++’, for extraction of the features (entity) data from the DXF file. The flow chart of the program is given as an appendix. The paper demonstrates the working of the algorithms using a set of examples.