Towards an object approach for quality monitoring and diagnosis on a galvanizing line

An integrated object approach for quality monitoring and diagnosis on a galvanizing line is presented. The aim is to diagnose the quality problems concerning the coated strip at the exit of the line. The diagnosis is mainly based on a “causal tree”, which associates to each symptom the possible explanations. These causes can often be considered as new abnormalities to detect, forming so the nodes of the tree, to which causes are also associated, and so on until the causes considered as primary. The route in the tree then links for each node new cycles of detection-diagnosis, taking into account specific models and variables. This study presents an organisation of knowledge of a diagnosis system based on an object approach using the object modelling technique