Abstract:Diagnostic strategy design is an important part of equipment testability work, which is of great significance to improve performance monitoring and fault diagnosis ability of equipment, reduce test and maintenance resource requirements, and reduce life cycle cost. By analyzing and summarizing the research results and relevant literatures at home and abroad, this paper systematically introduces the principle and classification of two kinds of diagnostic strategy design methods: AND/OR heuristic search method and intelligent optimization algorithm. The research status of diagnostic strategy design methods under complex conditions such as multiple fault condition, multiple valued test and unreliable test condition is analyzed and summarized. On this basis, the future research direction of diagnostic strategy design is discussed from three aspects.