改进的基于霍夫曼编码的故障诊断策略

Improved fault diagnosis strategy based on Huffman coding

针对电子系统的可测试性设计和故障诊断中测试排序问题,提出了一种改进的优选测试点和故障诊断树生成算法。在相关性矩阵模型的基础上,以平均测试代价最小和平均测试步骤最少为设计目标,采用基于霍夫曼编码的启发式函数优选测试点,提出了一步回溯的与或树启发式搜索算法生成诊断树,并给出了诊断策略优化方法的具体实现步骤。实例表明该方法可行,能以较小的平均测试代价和较少的平均测试步骤隔离系统的故障状态。

Aiming at the test sequencing problem in testability design and fault diagnosis of electronic system, an improved optimal test point seletion and diagnosis tree generation algorithm was presented. On the basis of the dependency matrix, with minimizing test cost and steps as the design goal, the algorithm used the heuristic function based on Huffman coding to select test points. And it put forward one-step-backward AND/OR tree heuristic search algorithm for diagnosis generation and offered the specific implementation steps of optimal method for fault diagnosis strategy. An example shows that the algorithm is feasible and can isolate the fault states of systems by using less test cost and steps.