Digital control: what do we want and what can we now achieve?

After reviewing at a simple level what the subject of control engineering deals with, several general control engineering challenges are described with the aid of examples - the challenge of complexity, as illustrated by flight control design, the challenge of achieving robustness, as illustrated by a guided vehicle control system, and the challenge of achieving adaptivity, as illustrated by sugar mill and alumina calciner control problems. The controller implementation challenge - of obtaining a simple computer-based controller to work with a complex plant - is also described.