Abstract
Although machining operation monitoring may significantly enhance manufacturing performance, industries remain hesitant to implement complex external sensor systems. We previously proposed a sensor-less method for monitoring the tool condition based on disturbance observer theory, but the applicability of this theory to tool wear monitoring has not yet been proven. The present paper advances and applies disturbance observer theory to tool wear monitoring during drilling. The experimental results showed the feasibility of determining wear-induced increases in the cutting load. Future research will involve extending the wear monitoring approach to other manufacturing processes.
