Gas Metal Arc Welding: Sensing

Sensoring Fusion Data from the Optic and Acoustic Emissions of Electric Arcs in the GMAW-S Process for Welding Quality Assessment

“…In KF fusion method there are two broad approaches: measurement fusion and state-vector fusion. State-vector fusion is preferable in such practical situations [ 12 ]. In such a system, each sensor uses an estimator that obtains an estimate of the state vector and its associated covariance matrices from the data of that associated emission sensor.…”

“…Figure 1(b) shows the infrared radiation response and as it can be seen, infrared emissions do not match the arc voltage and welding current behavior (see Figure 1(a) ), but by monitoring IR emissions, it is possible to monitor features such as bead width and penetration [ 1 , 12 , 13 ]. In the next section it will be shown that the infrared radiation has a direct relation with the welding arc power.…”

Robust estimation of arc length in a GMAW process by an adaptive extended Kalman filter

“…Among many types of welding methods, gas metal arc welding (GMAW) is very attractive because of its high speed, and both manual and automatic modes of operation for the wide range of ferrous and non-ferrous metal parts. In a GMAW process, the heat is generated by an electric arc and incorporates a continuously feed consumable electrode shielded by an externally supplied gas (Naidu et al, 2003). Like other types of electrical arc based welding, arc current (welding current) and arc length are important variables in GMAW.…”

“…Arc current can be measured by a current shunt or by Hall sensors (Naidu et al, 2003), but an accurate measurement of arc length is not easy; for example, the measuring of droplet size requires some expensive and complicated sensors. Usually these measurements are time consuming and are not suitable for online control purposes (Mousavi Anzehaee and Haeri, 2011b).…”

“…The second method is based on the measurements of non-inherent external signals, such as sound and light emitted from the welding (Madigan, 1994). In Li and Zhang (2001), Masumoto et al (1983), Naidu et al (2003), Richardson and Edwards (1995), Ushio and Mao (1994), and Wang and Li (1997), some methods such as machine vision, measuring through the light and sound of the arc, and also through-the-arc sensing methods were introduced to determine the arc length. The machine vision-based methods are expensive and time consuming because of their high computational requirements.…”