Comprehensive Tool Wear Estimation in Finish-Machining via Multivariate Time-Series Analysis of 3-D Cutting Forces

In finish-machining, geometric accuracy and surface quality m adversely affected by the tool wear at the minor flank and nose area. This paper describes an investigation into "comprehensive" tool wear estimation, including flank-, crater-. minor flank-, and nose-wear, based on an analysis of dynamic cutting force in oblique machining. The force, measured in terms of its three orthogonal components, was used to develop trivariate Autoregressive Moving Average Vector (ARMAV) time series models. Based on these, dispersion analysis (DA) was used to extract featurcs sensitive to the rate of various types of wear. The results show that minor flank wear reaches a critical value first in finish-machining, so that optimum cutting conditions or an appropriate tool change smtegy must be determined on the basis of minor flank wear. The results also show that the method is a feasible means for on-line tool wear monitoring in finish-machining.