Study on real-time measurement of nugget diameter for resistance spot welding using a neuro-fuzzy algorithm

Resistance spot welding (RSW) is still the most successful sheet metal joining method in the automobile industry. However, an effective quality evaluation method has not yet been developed. Real-time quality inspection of RSW is necessary in order to deal with all kinds of problems during welding. This paper developed an experimental system using for measuring electrode displacement. Accordingly based on electrode displacement curve proposes a neuro-fuzzy algorithm to inference nugget diameter online. Inference results showed that among the total number of specimens, 88% were successfully inferred within a range of 1.5% error.