Correlating Control Inputs and Web Roll Quality in a Roll-To-Roll System for Digital Twins

The dynamics of winding systems in roll-to-roll processes critically influence the roll quality. As direct measurement of web parameters near the winder and rewinder is often impractical due to cost and complexity, the state of the roll remains unknown. To overcome this challenge, this paper presents a novel condition monitoring methodology that estimates variations in web roll parameters such as thickness, roll density, and inertia. This eventually facilitates the computation of internal stresses in the web roll. This methodology integrates physics-based modeling with real-time data, which is made possible with a digital twin platform, thus enabling precise quality tracking in real time. Compared to conventional monitoring techniques, the proposed approach reduces reliance on physical sensors and provides a scope for the user to utilize real-time feedback to integrate a product-level control. Experimental validation demonstrates the effectiveness of the methodology by identifying roll quality and hence provides scope for optimizing the process control.