On Line Monitoring of Micro End Tool Wear Based on One-dmensional Fractal

Abstract

Based on the theoretical derivation of one-dimensional fractal, a new method to realize on-line tool wear monitoring of micro end tool is proposed. First, several different wear conditions of micro end tool are chosen as comparison samples, which includes the wear rate of micro end tool is 0, 10, 20, 30, $i$ and tipping respectively. The vibration signals of all samples are collected in time domain, and the range $k$ of each wear status is obtained based on one-dimensional fractal. Secondly, the vibration status of tested tool is monitored and analyzed, and its one-dimensional fractal is extracted. Finally, comparing the one-dimensional fractal of the tested tool with the fractal dimension range $j$ of the comparison samples, the status of tested tool is detected. In order to verify the above monitoring method, a small triaxial vertical testing machine is used. The results show that the one-dimensional fractal of each monitored micro end tool falls within the range of fractal dimension corresponding to actual wear.