Applying testability analysis for integrated diagnostics

The use of measures that evaluate system testability at a specific time during system design is demonstrated. The measures were detailed in a previous article (see ibid., vol.9, no.1, p.40-54 (1992)). The measures improve testability as part of an interactive process. The objective in applying the testability measures is to minimize ambiguity in replaceable unit groups while minimizing the amount of testing and the number of tests. The problems of excess information provided by a test set, ambiguity arising from deficiencies in the test set, multiple failure, and the test set's effect on false-alarm tolerance are examined. The analysis techniques are applied to a specific example, the antitank missile launcher, and the ways in which the testability of that system might be improved are discussed.<<ETX>>