Integrated and efficient cutter-workpiece engagement determination in three-axis milling via voxel modeling

This paper presents a new and highly efficient voxel modeling method to determine cutter-workpiece engagement (CWE) in three-axis milling. The method voxelizes both the workpiece and milling cutter in a voxel-based machining simulation space. This allows workpiece model update during machining to be done without the intensive intersection calculations between the cutter and workpiece. In addition, unlike the existing methods that update workpiece and compute CWE individually, the updated workpiece model and CWE are computed in an integrated fashion in the present work. This further reduces the involved computational load. At each cutter location, a voxel model of the cutter surface is created first by slicing the cutter surface by the voxel layer boundary planes to obtain a sequence of circles along the cutter axis. A main contribution of this work is the development of a unique fast increment and decrement scheme to voxelize each circle. Workpiece update and CWE determination can then be done simultaneously from the created voxel model of the cutter surface. A series of case studies have been performed to demonstrate the effectiveness of the proposed method. It can be seen that the proposed method is able to compute CWE very efficiently while maintaining accuracy comparable to the specified voxel size.