A framework illustrating decision-making in operator assistance systems and its application to a roll forming process

Abstract

The transformation from contemporary, mechanically dominated and experience based manufacturing processes such as forming to digital and fully automatic ones requires extended knowledge about defect detection along with target-oriented selection of adjustments. According to existing models, operator assistance systems can support the choice of expedient adjustment on the basis of correlations between sensor signals, process conditions, and required adjustments. However, the general understanding of the term and the operation of operator assistance systems varies widely. A comprehensive knowledge on these issues is required for the future development of assistance systems. Therefore, this paper introduces a comprehensive framework describing the decision-making in assistance systems. According to this model, assistance systems compare real-time process data such as sensor data to the desired process status. If a mismatch is observed, the assistance system evaluates its cause and suggests expedient adjustments. In order to create a common understanding of the operations executed by the system, the complex decision-making process within these systems is simplified in a model relying on matrix multiplications. The theoretical framework is applied to a roll forming process. This application illustrates how operator assistance systems successfully contribute to the continuous improvement of roll forming processes with respect to product quality and energy efficiency.