关键词: 层次系统, 测试性设计, 分层顺序测试, 启发式函数, 搜索算法, 故障诊断

Abstract: Aiming at the problem of fault isolation in hierarchical systems, an optimization method of hierarchical sequential testing was presented. Firstly, a mathematic model was constructed to deal with fault isolation. This model mainly considered the associations among fault sources and available testing of hierarchical system, the affiliation of faults with replaceable units in different levels, the prior probability of fault sources and the available testing costs. Secondly, a quasi multi-step look-ahead search algorithm was presented which employed the information gain as its heuristics. This algorithm could realize optimization of testing sequence in different isolation levels. Finally, a satellite power system was given to verify the method. Experimental result showed that the method could remarkably improve the efficiency of fault isolation in hierarchical systems.

Key words: hierarchical systems, design for testability, hierarchical sequential testing, heuristic function, search algorithm