Recent Advances in Resistance Spot Welding Control

Resistance spot welding is one of the most important welding procedures. Therefore, a lot of research is done in order to increase its cost effectiveness and ensure the quality of the welds. One of the areas within the field of resistance spot welding which directly addresses these goals is the development of the appropriate control algorithms. Common algorithms which work fine with mild steel prove to be inappropriate with new advanced materials. This paper presents recent advances in the development of control strategies. Due to the highly complex nature of the process an emphasis is given on artificial intelligence based control algorithms such as neural networks and fuzzy logic. This approach makes it possible to easily fuse information from different signals such as welding voltage, welding current, welding force, electrode displacement, etc. It therefore gives a more reliable estimation of weld quality or enables the application of better real time control algorithms. A very promising field of research within resistance spot welding seems to be the application of machine vision. A short introduction to this very interesting field is given in the paper as well.