The aim of this thesis is to analyze the stability of a important class of control systems, namely, feedback systems whose forward path contains nonlinear time-invariant or nonlinear time-varying subsystems and whose feedback path contains a memory less time-invariant nonlinearity (fuzzy logic controller). Stability condition in the sense of Liapunov for each system configuration is given. These conditions can be used for the analysis and design of fuzzy control systems. The drawback of previous work (can't include plant-nonlinearity) on the stability analysis of the fuzzy logic control system is overcome. Some examples are included to illustrate the approach.
