Paper:

# Monitoring and Adaptive Process Control of Wire Electrical Discharge Turning

## Mu-Tian Yan and Pai-Hung Hsieh

Department of Mechatronic Engineering, Huafan University, No.1, Huafan Rd. Shihding Dist., New Taipei City 223, Taiwan R.O.C.

This paper presents a novel pulse discriminating and control system for the identification of spark gap states, process monitoring and control of Wire Electrical Discharge Turning (WEDT). The relation between the proportion of open circuit, normal spark, arc discharge, short circuit to total sparks (defined as open circuit ratio, normal spark ratio, arc discharge ratio and short circuit ratio, respectively), ignition delay time and metal removal rate were experimentally studied and analyzed. A fuzzy logic controller was proposed to control both the arc discharge ratio and ignition delay time at optimal levels by on-line regulation of table feed-rate and pulse off-time for adaptive control optimization of WEDT. Experimental results show that the developed process monitoring and control system results in faster machining and better machining stability as compared with a conventional servo feed control scheme for the WEDT process.

*Int. J. Automation Technol.*, Vol.8, No.3, pp. 468-477, 2014.

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