Fault detection observer design for Takagi-Sugeno fuzzy systems with finite-frequency specifications.

This paper addresses robust fault detection observer design for a class of discrete-time Takagi-Sugeno fuzzy systems with finite-frequency specifications. A novel design method is presented based on finite-frequency H_-/H_∞ indices and peak-to-peak analysis. The finite-frequency H_- and H_∞ indices are utilized to characterize fault sensitivity and disturbance robustness, respectively. Peak-to-peak analysis is used to derive a dynamic threshold. To further reduce the conservatism caused by predefined parameters, an iterative algorithm is developed. Both theoretical proof and simulation results show that the performance of the proposed method is not worse than the existing works.