New Method of On-Line Monitoring Tool Wear States Based on Fractal Dimension

On the basis of the theory of fractal geometry, the fractal dimension characters of AE signal at different tool wear states were analyzed, an algorithm was provided to decide the scale range which is necessary to calculate the dimension of non fully fractal form. The experiments showed that the fractal dimension of AE signal is slightly effected by the changes of cutting parameters; The variance of the fractal dimensions, which reflects the geometric characters of AE signals, has the same tendency as that of the flank wear, The monitoring system, which takes the fractal dimension of the AE signal as the feature, can identify the different tool wear states more correctly under different cutting conditions.