Establishing And Application Of The Detecting And Analysis Of Arc Welding Electric Parameters Based On ARM Microprocessor

The paper developed a Detecting and Analyzing System of CO2 Gas Shielded arc Welding based on droplet short-circuiting transfer process. The system made a progress in the cross-subject field by combining the welding with the three advanced technologies such as 32 -bit ARM microprocessor, USB (Universal Serial Bus) interface device and Visual Instrument and so on.The hardware circuit of the system consisted of the Hall voltage sensor, the Hall current sensor and the circuit of signal debug, the LPC2142 Pack base on ARM chip and the other needed components. Because of USB controller and A/D unit embedded in LPC2142 Pack, the hardware design was more convenient and easier. the system had higher transmission speed in virtue of both characteristics of ARM microprocessor and the plug&play. Besides, Compared with general data acquisition card, it is much cheaper, more flexible.The software system was composed of the LPC2142 microprocessor firmware program, the USB driver program and the user application program. The microprocessor firmware program was developed by C language and assemble language. Both the USB driver program and user application program were created by LabVIEW (Laboratory virtual instrument engineering workbench), a virtual instrument programming software which developed by American National Instrument Corporation, and made the whole developing process more easily and low-cost.The system was successful in acquiring and process the signal of the current and voltage of the CO2 gas shielded droplet short-circuiting transfer. It meaned that one could implement signal real time acquisition, dynamically display, data save and draw instantaneous U-I curve, get probability density distribution about arc voltage and welding current and gain frequence-distribution curve about arc cycle and short-circuit cycle and so on. All of these could serve to the quality detect online of the current and voltage of the CO2 gas shielded droplet short-circuiting transfer. And it also provided an easy way to evaluate the welding process stability directly and precisely.In the end, the system was tested by CO2 gas shield droplet short-circuiting transfer experiment. Two workpieces were select to be welded with different welding parameters. The system could perform well in the acquiring function and analysis function. Contrasting the two different results, the reliability and practicability of the system was validated.