Delay-Dependent Feedback Control of Printing Positioning in Multi-Color Printing Lines

This paper focus on design of control schemes for multi-color printing press which is a typical web handling system. In the printing press consisting of multi printing units, the dynamics between two neighboring printing units are coupled, and the coupling effects propagate to downstream units with delay. This paper presents a model-based nonlinear control strategy for printing positioning control in a three-color printing press. First, a nonlinear coordinate change is introduced to a state space model. Then, based on the new dynamical model, two feedback control schemes are proposed. A state feedback controller is designed such that tension error and printing error converge to zero. The state feedback controller requests the tension of the web to be measurable. In order to avoid the constraint, an observer-based feedback controller is proposed with stability analysis. Furthermore, the effectiveness of the proposed control scheme is demonstrated through simulation.