This application relates to a
machine learning-based method and
system for
quality monitoring of self-piercing riveted joints. The method includes: acquiring dynamic physical process diagrams of
acoustic emission events during the self-piercing riveting process, and summarizing these events chronologically to obtain a sequence of dynamic physical process diagrams; constructing and training a multimodal spatiotemporal graph convolutional
network model based on a physical constraint
loss function; inputting the sequence of dynamic physical process diagrams into the trained graph convolutional
network model, outputting a three-dimensional
residual stress field, and mapping it onto the geometric model of the riveting area to obtain a three-dimensional stress cloud map and perform
quality assessment to obtain the joint quality grade; combining the spatial coordinates of the three-dimensional stress cloud map, the joint quality grade, and the maximum residual tensile stress value to obtain the joint
quality monitoring result. This method, by embedding a
network model with physical constraints, can still output a physically consistent
stress field distribution even in the absence of a large amount of
labeled data, significantly improving the depth and reliability of monitoring.