Automatic generation of part programs for milling sculptured surfaces

In recent years, a large number of commercially available CAD/CAMCAE packages as well as computer numerically controlled machine tools have been imported into Iranian manufacturing industry. However, there has been no easy-to-use link or interface between the two. In this paper, an attempt is made to establish a simple but effective software to link CAD packages and CNC machine tools. To achieve this, a software package was developed capable of exploring Initial Graphics Exchange Specifications (IGES) files of simple or free-form surfaces created on any CAD package. The data extracted from IGES files is used to graphically simulate tool path due to centre and tip of a ball nose tool and a filleted cutter as well as tip of a flat end mill cutter. Depending on the size of created surfaces, various dimensions of cutting tools should be selected by the user. Other features included in this package are the ability to automatically detect the correct machining direction and correct machining side of surface, calculation of tool compensation and tool step. Obviously, its main feature is its ability to automatically generate part programs for machining sculptured surfaces. Number of such surfaces were created on CAD systems and the generated tool path were successfully simulated and a few are presented in this paper.