Adaptive H_∞ Tracking Control Of Multiple Input Multiple Output Nonlinear Systems

Since most of the practical systems are nonlinear and uncertain, so the robust tracking control of nonlinear uncertain systems is an important topic in the field of control. In the last decade, the approach of H_∞ optimal control has been widely discussed for its robustness and capability of disturbance attenuation in linear and nonlinear control systems involving external disturbances. The related generalization of H_∞ control for nonlinear systems has also received a great deal of attention in the recent years. Various feedback control schemes have been developed by many researchers. However, in these conventional H_∞ tracking control, the plant models must be known. If the plant models have large uncertainties, the conventional H_∞ tracking control will meet additional difficulties. Therefore, an additional approach (for example, adaptive control technique) must be incorporated into the pure H_∞ tracking control design for nonlinear systems with uncertainties and external disturbances.At the same time, due to various reasons, unmodeled dynamics can be produced in practical systems. One of the reasons is that it is very difficult to find the accurate models of systems. On the other hand, some dynamic properties of systems will be lost when simplifying the model to acquire the convenience of research. Unmodeled dynamics exist in any...