The system described in this article is currently working in the field at the Sales Department of EKATO, one of the world's most successful manufacturers of industrial mixing machines. It was developed in close cooperation with the Fraunhofer Institute for Information and Data Processing (IITB) during a three-year period. Industrial mixing machines, better known as agitators, are widely used in industrial manufacturing. They are especially useful for the chemical and pharmaceutical industries, food production, and biotechnology. The basic structure of an industrial agitator is shown in figure 1.

Although there are designers who claim design is a mysterious activity not amenable to scientific examination, research into design continues Although there are publications by designers on how to design dating back to Roman times, notably by Vitruvius, the nineteenthcentury design thinkers actually began work on articulating design as a process (Durand 1802). However, it was not until the 1960s that major research programs were initiated. These programs were originally founded on the systems view and used concepts from operations research (Jones and Thornley 1963). More recently, information-processing models founded on AI concepts have provided an impetus for renewed research into design in its various aspects (Simon 1969; Coyne et al. 1990). Many foundational ideas in AI are proving to be useful in developing formal models of design as an activity.

COMIX (configuration of mixing machines) is a system that assists members of the EKATO Sales Department in designing a mixing machine that fulfills the requirements of a customer. It is used to help the engineer design the requested machine and prepare an offer that's to be submitted to the customer. During the process of routine design, some design decisions have to be made with uncertainty. The success of the system can be measured by the increase in the quantity and the quality of the submitted offers.