Algorithm Development for Tool Path Generation for Three-axis Sculptured Surface Machining

Abstract

The sculptured surfaces are widely used in aerospace wings, car bodies, gas-turbine blades, ships, die and mold making, medical parts etc. Manufacturing of these parts requires high degree of accuracy and surface finish because of their aero and fluid dynamic properties. The strategy of tool paths have big impact on machining of sculptured surface. There are many methods had been developed for 3-axis and 5-axis machines to deal with accuracy, surface finish and total machining time. In this dissertation, the Iso-planar method is selected to generate tool path because of its simplicity and robustness. This iso-planar method is applied to any polyhedral model to generate tool path for 3-axis CNC machines. The .STL file was created from polyhedral model to generate triangular facets from model. A MATLAB programme is developed to gather all the vertices and facet normal data. The drive planes are introduced throughout the triangular surface to get the intersection points between plane and triangular facets which is known as CL data for tool path. Rough cut paths and finish cut paths are then generated for complete machining. The G code file executed by MATLAB programme has been validated with NX CAM software as well as experimental setup on VMC machine.