A New System-Level Approach to Diagnosability.

This paper presents a new approach to determine the conditions that ensure diagnosability properties in complex systems. In previous approaches, a fault-test relationship is assumed and all diagnosability conditions depend on both this relationship and the desired diagnosability property. In our approach, such assumptions are not required, so that diagnosability conditions depend only on the desired diagnosability property. This method uses a new system-level fault model having both internal and observable test outcomes and allowing multiple test outcomes to be associated with each fault situation. By defining different sets of internal test outcomes, one can represent the desirable diagnostic properties of the model. In this paper, diagnosability conditions for models possessing morphic properties are given. As an example, the conditions are applied to the fault model of Preparata, Metze and Chien. The results obtained demonstrate that 1 new diagnosability conditions can be determined and 2 the previous diagnosability conditions can be reconstructed and applied to a larger class of fault models. Author