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This thesis is aimed at enhancing the accuracy and the sustainability of the micro Milling Electrical-Discharge Machining process. A framework for the simulation and validation of tool wear compensation models is developed. An on-line tool wear compensation method based on discharge counting and tool wear per discharge is proposed. The mean discharge energy and the variability of the characteristics of the discharges acquired during a pocketing operation are analysed. Optimal trigger values for discharge counting are defined. A custom hardware interface and software protocol to command the micro EDM machine from Matlab programming language is developed and tested. A strategy to perform on-machine volume measurement is developed and the repeatability and uncertainty of measures are studied. An evaluation of the errors affecting micro EDM on-machine measurements is carried out. The custom communication interface and the on-machine measurement procedure are employed in automatic assessment of material removal and tool wear per discharge. The procedure is tested in a wide range of process parameters and the variability of MRD and TWD values are evaluated. A material removal simulation tool for accurate workpiece representation of the machined geometry, based on MRD and counted discharges, is developed and validated. Finally, a low-cost, modular framework for remote energy monitoring, based on open-hardware and open-source software is developed and employed for the energy efficiency analysis of the micro EDM machine. Expedients to improve the energy efficiency of the micro EDM machine and of the process are suggested. |
