Abstract: As abundant information sources, arc spectrum, which reflects all sorts of physical process, makes us sense and control metal transfer perfectly. On the basis of embedded study on spectrum emission of welding arc and reception system, the spectrograph and complicate light route system are abandoned and the filter and light spectrum window are selected substitutively. And the spectral sensor is designed and manufactured here, by which the metal transfer of project transfer arc are observed and controlled precisely. The success of the study provides a new way to control the welding process.

Key words: Arc spectrum, Control, Metal transfer, Sensing