This paper presents new relaxed stability conditions and LMI(linear matrix inequality) based designs for both continuous and discrete fuzzy control systems. They are applied to design problems of fuzzy regulators and fuzzy observers. First, Takagi and Sugeno’s fuzzy models and some stability results are recalled. To design fuzzy regulators and fuzzy observers, nonlinear systems are represented ...

In this note, the problem of states and unknown inputs estimation of nonlinear descriptor system is considered. The methodology is based on the use of Proportional Integral and Unknown Input Observers. The considered nonlinear descriptor system is transformed into an equivalent multi-models form by using the Takagi-Sugeno (T-S) approach. In this paper, the design methods of both proportional in...

We propose a redesign paradigm for stable estimators by introducing saturation or dead-zone nonlinearity with adaptive thresholds on the output injection term. Such nonlinearities allow improving sensitivity to measurement noise in different scenarios (impulsive disturbances persistent such as sensor bias), while preserving asymptotic convergence properties of original observer. These redesigns...