Conductance sensing for monitoring micromechanical machining of conductive materials

• A sensoring system for real time tool-workpiece monitoring was presented.
• A sensor designed to monitor conductance along the tool edge-workpiece was employed.
• The effectiveness of the conductivity sensor was verified in micromilling operations.
• Measurement the drop in the AC current voltage the contact resistance was calculated.
• A success rate of 90% of the prototype to detect the cutting states was demonstrated.

A sensoring system is presented for high-precision monitoring in real time of tool-workpiece interaction and cutting detection in micromachining operations. It employs a sensor designed to monitor conductance along the tool edge and the material. The results are theoretically applicable to all machining and milling operations on conductive materials. Contact resistance is calculated by measurement of the drop in the AC current voltage flowing through the interaction impedance of the spindle, the tool and the workpiece. The effectiveness of the conductivity sensor is experimentally verified in several micromachining operations. An assessment of the prototype demonstrated a success rate of 90% in detecting the cutting states. These results hold the potential to improve the implementation of embedded systems for real-time tool-condition monitoring of micromachining processes at an industrial level.