A systematic procedure to synthesize interval observers for nonlinear discrete-time systems is proposed. The feedback gains and other matrices are found from the solutions to semidefinite feasibility programs. Two cases are considered: (1) the interval observer is in the same coordinate frame as the given system, and (2) the interval observer uses a coordinate transformation. The conditions where coordinate transformations are necessary are detailed. Numerical examples are provided to showcase the effectiveness of the interval observers and demonstrate their application to sampled-data systems.
Interval Observer Design Using Observability Decomposition for Detectable Linear Systems
University of Illinois Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校）；Conservatoire National des Arts et Métiers (CNAM)（国立工艺学院）；Harbin Institute of Technology（哈尔滨工业大学）
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