Knowledge-based robust control of complex systems

In this paper we integrate a knowledge-based system into an algebraic controller, namely, a variable structure controller. The resulting knowledge-based controller has two hierarchical levels. The highest level consists of a knowledge-based system which contains a qualitative domain knowledge which is expressed in terms of a set of linguistic statements in the form of fuzzy if-then rules. These fuzzy rules qualitatively describe how the variable structure control functions should be executed in order to achieve a better performance. The lowest level consists of a variable structure control algorithm. The rationale for the integration of knowledge-based techniques into variable structure control approach was originally discussed by the authors. In this paper the structure of the knowledge-based controller is further explored within the framework of intelligent control. To verify the performance of the proposed knowledge-based controller, the latter is applied to the control of a robot manipulator