Conductance sensor for micromachining. A case study on monitoring tool-workpiece contact

This paper proposes a conductance sensor and a procedure for real-time monitoring of micromaching processes. This procedure is based on a computationally efficient method to detect both the state of tool-workpiece contact dynamic and tool breakage. The measurement of electrical voltage drop is done by supplying an AC current through the contact impedance and this is the main input signal of the algorithm. The design of a conductance sensor is verified experimentally. The assessment of the prototype demonstrates a success rate of 90% in detecting the cutting states. These results are the basis for developing and implementing embedded system for real-time and tool condition monitoring of micromachining processes at industrial level.