Criteria for the complementary allocation of functions in automated work systems and their use in simultaneous engineering projects

Abstract

A crucial step in any system design concerns the allocation of functions between human and machine. In simultaneous engineering, function allocation is potentially an issue both in product design — if the product is a technical system itself — and in process design. It is argued that well-founded function allocation decisions in relation to the production process are of particular importance in simultaneous engineering as less and less time is allowed for compensation for inadequate or missing decisions which will impede production effectiveness. The focus of recent methods for the allocation of functions is to operationalize the concept of complementarity, meaning to provide guidelines for complementing humans by technical systems instead of replacing them gradually as technical systems become more and more sophisticated. As systems design becomes more complex, involving more and faster changes and placing higher demands on engineers as well as system operators, the idea of complementary gains importance because it stresses the need to allocate functions in a way that supports human control over the production process and the development and maintenance of the necessary skills. Looking at existing methods and instruments for the complementary allocation of functions, one is at first sight confronted with a multitude of criteria for complementarity, but to date neither a fixed set of criteria, comparable to software usability criteria, nor widely accepted methods for their measurement exist. As part of a research project concerned with the development of guidelines whose objective is to assist engineers in designing work systems according to the complementarity principle, four central criteria for complementary function allocation were identified: dynamic coupling, process transparency, human decision authority, and flexibility. These criteria and their application in a design process are illustrated by means of a case study and discussed in terms of other approaches to complementary design as well as their use for simultaneous engineering projects. Relevance to industry Adequate allocation of functions between human and machine is crucial for the effectiveness of any production system. With more complex and faster design processes in simultaneous engineering projects, the need for methods supporting prospective analysis and design of human-machine systems has increased even more. The article presents such a method based on the principle of complementarity between human operator and technical system and illustrates its use by means of a case study.