Modeling and conventional/adaptive PI control of a Lathe cutting process

A mathematical model for predicting dynamics between the feedrate and cutting force in the lathe cutting process is presented. The model comes from combinations of a parameter identification technique and geometrical consideration for chip thickness time variation. The model prediction of transient responses is in good agreement with the experimental results. The model is used for tuning a PI controller for regulating the cutting force as well as to show performance limitations of the conventional PI controller. A simple adaptive control scheme that makes use of the model structure is proposed. Experimental results from laboratory evaluation of the proposed controllers are presented.