|Unknown Input Observer Design for Takagi-Sugeno Fuzzy Stochastic System
Shenghui Guo, Fanglai Zhu, and Liyun Xu*
International Journal of Control, Automation, and Systems, vol. 13, no. 4, pp.1003-1009, 2015
Abstract : This paper deals with the unknown input observer design for Takagi-Sugeno (T-S) fuzzy models subjected to measurement noise and stochastic noise. The method applies the singular system theory by considering the measurement noise as an augmented system state, and then an unknown input observer based on the techniques of singular systems is developed to estimate both the system states and measurement noise simultaneously. Under a necessary assumption, the error dynamic system of the observer is free from the unknown inputs. And the observer gain matrix is determined by means of minimum covariance matrix of state residual. Two simulation examples are given to illustrate the correctness and effectiveness of the proposed method.
Keyword : Covariance matrix, singular system, stochastic system, T-S fuzzy models, unknown input observer.