Online monitoring system and method for stainless steel train body laser welding quality

The invention discloses an online monitoring system for the stainless steel train body laser welding quality. The online monitoring system comprises a workpiece, a laser generator, a signal pickup device, a signal processing circuit and a data collecting and signal analyzing circuit. The laser generator is arranged over the workpiece. The output end of the signal pickup device is connected with the input end of the signal processing circuit. The output end of the signal processing circuit is connected with the input end of the data collecting and signal analyzing circuit. The laser generator is used for machining a workpiece, the signal pickup device is used for accurately obtaining information reflecting the workpiece processing quality in the laser generator processing process and transmitting the information to the signal processing circuit. The signal processing circuit is used for converting sensing signals or amplifying and conveying the sensing signals to the data collecting and signal analyzing circui