Five-axis NC machining of compound sculptured surfaces

Five-axis milling machines have been used mostly to cut special mechanical parts, such as aircraft parts, impellers, propellers, and so on. Recently, it has started to use them in more general applications, such as the machining of sculptured surfaces in dies and molds. This is because 5-axis machines offer better cutting efficiency and improved surface finish as well as the machinability of vertically hidden surfaces over the conventional 3-axis machines. However, problems still exist in the 5-axis machining of sculptured surfaces. While the additional two rotational axes offer more flexibility, it is not easy to control them properly in practice. In this research, practical methods to generate cutter paths for the 5-axis machining of compound surfaces are developed. A compound surface is a part surface model that consists of multiple elements. Free-form objects are often designed by compound surfaces. The research is focused on the following three major issues: (1) Setup-orientation determination in 5-axis machining, (2) Cutter-path generation for 5-axis side milling, and (3) Cutter-path generation for 5-axis face milling. A compound surface is first checked if it can be cut by the target 5-axis machine. The feasible setup orientation of the surface is also determined. Cutter paths are then generated. The cutter-surface interference is avoided during the cutter-path generation. By developing methods for cutting both the vertical and horizontal compound surfaces, most of the applications of 5-axis sculptured surface machining are covered. The compound surface model is inputted using IGES files