Tool path linearization algorithm and postprocessor for five-axis CNC machine

Abstract

When cutter location (CL) data are generated by the CAM system, it is assumed that the tool path between two CL points is a straight line relative to the workpiece. However, this is only the case for the simultaneous motion in three linear axes, for the case of five-axis machine, due to the rotary axes, the tool path between two blocks in the NC program will be non-linear relative to the workpiece, reducing the accuracy of the tool path. This paper presents a tool path linearization algorithm and a postprocessor for five-axis CNC machine that allows to reduce the tool path error. A windows-based software module written in Visual Basic was developed according to the presented method. The five-axis CNC milling machine tool with two rotary axes on the table (Deckel Maho DMU 70 eVoluion) was used to demonstrate and validate the linearized CL data generated by the proposed method and postprocessor. The simulation result shows that the proposed method can reduce the error of the tool path; the postprocessor is reliable and can be customized to apply for any types of five-axis CNC machine configuration.