Stability indices for the global analysis of expert control systems

The stability of rule-based expert control systems is studied. A control structure with a nonlinear plant and a nonlinear controller, designed on the basis of logical rules incorporating the experience of designers and human operators, is considered. Two classes of indices are presented: one related to the relative stability of the equilibrium point at the origin, and the other to the global stability of the system. These indices can be used for the analysis and design of expert control systems. Some examples are included to illustrate the approach