Resuming Milling Process after Intra-Operational Interruptions Based on the Enhanced NC Simulation

In this thesis, a methodology for generating the virtual workpiece (VWP) by means of swept volume (SV) of prevailing cutting tools undergoing simultaneous five-axis motion is proposed and proved to be amenable for practical purposes through a series of tests. The exact and complete SV, which is closed from the tool bottom to the top of the tool shaft, is generated by interpolating envelope profiles calculated by the Gauss map. Furthermore, the engagement of the cutter undergoing self-penetration is analyzed in an in-depth manner. To verify the proposed method, a cutting simulation kernel for five-axis machining is developed.
Based on the proposed method, a collision-free re-approaching tool path is generated. Thereby, a visibility cone is calculated via VWP from which inward spherical offsets are generated. The deepest point, which is the point determined by maximal offset radius, from the boundary of the visibility cone is determined as a re-approaching tool axis to resume milling process of the intra-operational interruptions. The strategy enables the machine operator to tackle unwanted machining conditions, e. g. tool breakage which has been demonstrated by a planned scenario.