Integration of feature recognition and CNC code generation for AXI symmetric rotary parts in a typical CIM environment

Abstract

In the current global business environment the focus is on increased quality and reduced cycle times. In spite of advanced manufacturing and automation technology, the link between CAD and CAM is still not as integrated as desired. Although in most circumstances CAD data can be processed within the CIM environment by integrated software components to produce information like manufacturing data, assembly data, etc., there are a significant number of cases where an external CAD resource needs to be processed for further integration with CAM. In this context, this research work aims at developing a novel approach to integrate CAD and CAM, specifically for the rotary parts drawn in any CAD environment and finally to generate a CNC part program for the same. The proposed system is developed in four phases. The first phase involves, getting a CAD model of 2D upper half profile of the required component drawn in any CAD environment and converted to DXF data structure. The second phase is about Data extraction system which is used to extract the useful geometrical data pertaining to the component from its corresponding DXF file. The third phase, Feature Recognition system, is used to organize the data extracted from the DXF file and present the same in the form of a more meaningful data, called as design features, using syntactic pattern recognition technique. Feature Mapping is performed to map the design features in to thecorresponding predefined manufacturing features. Rule-based process sequencing is performed to sequence the machining operations. The final phase involves the generation of CNC part Program. Several algorithms were developed to translate the design data to the corresponding CNC codes. A software program in ?C? is developed for extraction of the feature data from the related DXF file and for the generation of the part program. The output of the program is given in the form of text files. Based on the proposed novel approach simulation runs are carried out and the results were found to be satisfactory.