Overall fault diagnosability evaluation for dynamic systems: A quantitative–qualitative approach

The issue of overall fault diagnosability evaluation is addressed to provide a standard for system design from the fault diagnosis perspective. An overall fault diagnosability measure is first defined statistically by combining quantitative and qualitative evaluation results. On this basis, a randomized algorithm-based method is developed for estimating this quantitative–qualitative measure with a preset accuracy. Then, a tractable method for computing the lower bound of the measure is created, which provides a way to assess fault diagnosis performance without a large computational burden. Finally, a spacecraft attitude control system is used to verify the effectiveness of the proposed methods.