Cutting State Estimation via Chatter Mark on End Milled Surface and Analysis of Its Formation Mechanism Using Voxel Model Simulation

Abstract

Abstract When chatter vibrations occur during cutting, a characteristic pattern called chatter mark appears on the machined surface. In our previous studies, it was estimated that this chatter mark is formed by the tool (or workpiece) vibration in the normal direction with respect to the machined surface. We thus proposed a method to inversely analyze the chatter vibration information during cutting through the chatter mark using two-dimensional discrete Fourier transform. Previous studies confirmed that the analysis results of this method are in good agreement with those of the information obtained via conventional sensing. However, the correctness of the pattern formation mechanism is yet to be directly verified, as it is difficult to measure the cutting phenomenon directly. In this study, the chatter vibration during cutting was measured by the displacement of the tool-shank. Then, based on the results obtained in the static stiffness test, the movement of the tool edge was estimated. A cutting simulation using a voxel model was executed based on this tool-edge movement. When the simulation using the chatter vibration in the normal direction was performed, a chatter mark appeared on the simulated surface. It could thus be confirmed more directly that the analytical model is correct compared with the previous methods.