Process industries versus discrete processing: How system characteristics affect operator tasks
Despite an increasing level of automation, human operators still play a central role in industrial production. They need to monitor and adjust plant operations, compensate for process deviations, and step in when abnormal situations cannot be handled by the automation but require diagnosis and adaptive intervention. Based on a literature review, the article presents a cross-domain comparison of operator tasks and the associated knowledge and information requirements for process control in the process industries and discrete processing. While the process industries are characterized by a transformation of uniform, shapeless materials in physical or chemical processes, discrete processing is concerned with all subsequent steps in the mass production of consumer goods. It is argued that operator roles in these domains differ considerably. First, we compare technical system characteristics with regard to complex interactions, production processes, materials and products, faults and abnormal situations, and the information available to operators. Second, we describe how these technical system characteristics lay the foundation for similarities and differences in operator roles, focusing on qualification and training, routine task characteristics, dealing with abnormal situations, and the associated challenges for operators. We discuss implications for operator empowerment and operator support by assistance systems.