H∞ filtering for a class of nonlinear systems

This paper investigates the problem of H_∞ filter design for a class of nonlinear systems. Attention is focused on solving the H_∞ fuzzy filter designed problem for interval type-2 (IT2) fuzzy systems. By using Lyapunov stability theory, an IT2 filter is designed such that the filtering error system is asymptotically stable with the prescribed H_∞ performance levels. The existence condition of the IT2 filter is expressed as the convex optimization problem and the filter parameters in the condition can be solved by the standard software. It is not requited that the IT2 fuzzy model and IT2 fuzzy filter share the same lower and upper membership functions. Finally, a numerical example is provided to show the effectiveness of the proposed results.