A delta approach adaptive observer for on-line tool wear estimation in turning

On-line tool wear estimation in turning is essential for on-line cutting process optimization. In this paper, a delta approach adaptive observer, based on cutting force measurement, is used for a reliable on-line flank wear estimation. The adaptive observer design combines optimal state estimation and a recursive least squares method as the adaptation algorithm. For model validation, the flank wear is estimated using a nonlinear model. The proposed approach improves the results previously proposed in other research works particularly concerning the number of identified parameters.