Cutting tool wear monitoring for reliability analysis using proportional hazards model

Aiming at operational reliability analysis and assessment based on condition monitoring information, a methodology of reliability modeling and assessment based on feature extraction from cutting tool vibration signals using proportional hazards model is proposed in this paper. Root mean square and peak of time domain index from vibration signals, which are closely related to cutting tool wear degradation states, are selected as covariates introduced to proportional hazards model for the cutting tool wear reliability analysis. The proposed approach shows considerable advantages of establishing significant association relationship between the cutting tool condition monitoring information and the life distribution of cutting tool wear. It is appropriate to provide individual cutting tool operational reliability assessment effectively. The experimental study on a CNC lathe turning process is given to validate the effectiveness of the proposed method. The results show that the approach is desirable and gives a good estimation of the reliability for cutting tool wear degradation states.