Simulation and performance evaluation of metal cutting processes from NC programs

Abstract

Existing NC verification tools concentrate on graphical display of tool path and collision detection only. The objective of this work is to demonstrate that information regarding the nature of machining being performed can be extracted from NC code, work and tool material properties, and initial geometric profile of workpiece. Based on this information, values of performance measures (such as cutting force, tool wear, cutting temperatures, chip formation and surface finish) can be estimated using theoretical or empirical models. A software simulation tool is developed to demonstrate this. The software tool runs under X-Windows on a Sun workstation. It generates the following output: graphical display of tool path, cutting forces, tool-chip interface temperature, flank wear of cutting tool, surface finish generated and nature of chip formation. At every stage of simulation, the current profile of workpiece resulting from each machining operation is computed, by finding regions of intersection of previous workpiece profile and current tool path. In its present version, this software tool is capable of simulating performance measures for turning operations only. However it can perform graphical display of 3-D toolpath.