Method for Unit Self-Diagnosis at System Level

Abstract

This paper suggests unconventional approach to system level self-diagnosis. Traditionally, system level self-diagnosis focuses on determining the state of the units which are tested by other system units. In contrast, the suggested approach utilizes the results of tests performed by a system unit to determine its own state. Such diagnosis is in many respects close to self-testing, since a unit evaluates its own state, which is inherent in selftesting. However, as distinct from self-testing, in the suggested approach a unit evaluates it on the basis of tests that it does not performs on itself, but on other system units. The paper considers different diagnosis models with various testing assignments and different faulty assumptions including permanent and intermittent faults, and hybrid-fault situations. The diagnosis algorithm for identifying the unit's state has been developed, and correctness of the algorithm has been verified by computer simulation experiments.