Fault Evolution Model of Manufacturing System Based on Small-world Networks

Manufacturing system is a multi-level complex dynamic system composed of different types of machines, and machine fault is a major factor of manufacturing system’s reliability. Hence, identification of fault evolution path and intensity is the prerequisite of fault prevention for complex manufacturing system. In this paper, a new multi-level model of fault evolution in manufacturing system is proposed. Based on the multi levels of manufacturing system, fault evolution path of manufacturing system has two types.One is physical evolutionpath within a single machine, and the other is flow evolutionpath during manufacturing process. Physical evolution has small-world characteristics, its intensity is the product of fault evolution probability and fault-load between fault nodes. Flow evolutionis judged by production relationships between machines, its intensity is production loss of manufacturing system due to unexpected shutdown of machines. Therefore, the integrated intensity of fault evolution within manufacturing system isthe comprehensive result of physical evolution and flow evolution.Then, ant colony algorithm isapplied to search fault evolution path with maximum intensity, sorting steps of fault evolution intensity is given to support decision making of fault prevention in manufacturing system. In the end, a case study of headstock manufacturing system is provided to verify the efficiency of the proposed method.