Abstract:

From the basic definition and analysis of fault isolation rate as a beginning, aiming at the early stage of weapon system development, after giving the percent of fault isolation, how to determine and optimize the corresponding fault isolation ambiguity group size is explored. Firstly, with the help of the multi-signal flow graph （MSFG） in the testability analysis and a typical example, and with different distribution of the fault isolation’s ambiguity group in the testability design, the full measurement of the fault isolation ambiguity group size is found out, that it should be a group of sizes included maximum, minimum and average size. And a single size, currently being used by people, should be considered as an average value. To qualitative analyze when lacking information, with a typical example, the method and principle to determine we presented maximum, minimum and average size of the fault isolation ambiguity group size, on the condition of giving the fault isolation percent. To quantitative analyze, through analyzing the process of equipment repairing and fault isolation, a general optimization model about the fault isolation ambiguity group size is established. As how to get the optimization solution, firstly the general model by the background of engineering practice is simplified, and the condition that the optimization solution exist is presented. Then through the logical and mathematics analysis, taking typical equipment’s repairing as an example, a method of step-by-step seeking for the optimization solution and an algorithm based on dynamic programming are completed. Using the models and methods, one can obtain the optimized accurate value of maximum, minimum and average size of the fault isolation ambiguity group size, on the condition of giving the fault isolation percent. So the problem about the fault isolation’s ambiguity group size can be solved entirely on the engineering background.