ABSTRACT
The aim of this introduction is to guide the reader through the content of subsequent chapters, offering a high-level presentation of the underlying concepts and ideas that appear all throughout the book. The most basic requirement for the controller K is internal stability, which means that all the relations in H are stable. Some basic problems with internal model control are related to servo/regulation issues. Apart from considering the inherent compromise between robustness and performance, extra design parameters will be finally introduced into the weight to deal with the trade-off between the servo and regulatory performance. In addition, the extension to plants with complex conjugate poles is addressed; for oscillating plants, it is especially important to distinguish between the servo and regulatory tasks.
