The invention relates to a vehicle body
assembly quality online diagnosis method based on component measuring point distance
abnormality judgment, which combines the vehicle body
assembly process relation and the clamp positioning
process information, extracts out-of-tolerance measuring points in measuring data of a
tail end detection
station, and achieves determination of defective components. The positioning of the faulty
station is realized by discriminating the potential faulty stations related to the defective components from top to bottom and judging and analyzing the difference between the actual distance and the
standard distance of the measuring points on the defective parts. In the fault
station, the relative distances between the key points on the defective parts are different, so as to achieve the diagnosis of the parts' defects. Meanwhile, according to the in-station deviation relation model and the
estimation method, the element positioning deviation is solved, so as to achieve the fault diagnosis of the clamp and to guide the making of the
assembly system maintenance strategy. With the method, the diagnosis precision is improved, the
system fault source can be found more timely based on the single-vehicle fault diagnosis, thereby reducing loss caused by the process
system fault.