Control Engineering at the Crossroads.

Control engineering, in a wider sense process automation, is at the crossroads. This point is characterized by rising requirements for the processes and thus also for the means of automation including theory. A special characteristic of the crossroads situation is on the one hand the advent of the so-called ″large scale systems″ and on the other hand the already starting development of decentralized automation systems that should be suitable for feedforward and feedback control of ″large scale systems″ . Many problems are still unsolved. With this contribution an analysis of the situation is given, perspectives for the near future are pointed out. To begin with, a historic survey highlights the development since 1950 and makes clear that the new means of automation will have a similarly decisive impact as the introduction of measuring transducers and standard signals in those days. Possibilities and limits of currently available methods and theories are discussed. Some challenges for a new theory of decentral systems are outlined.