Cooperative compensate register control for mechanical shaft driven roll-to-roll printing system with dancer rolls

Abstract

In mechanical shaft driven roll-to-roll (R2R) printing systems, tension propagation caused by the regulation of dancer rolls increase the control difficulty of the whole system. In this paper, a cooperative compensate control (CoComC) method is proposed for the R2R printing systems to attenuate tension fluctuation and reduce the register errors. Specifically, a mechanical model is established to quantify the relationship among the web tension, linear velocity of dancer roll and register error. Based on the model, a well-tuned feedback control law is designed for each dancer roll, and a cooperative matrix is proposed to coordinate the feedback control to attenuate the tension fluctuation and reduce the register error in the corresponding printing unit. Further, the stability and convergence condition of the proposed control system are provided and proved via Lyapunov stability theory. The effectiveness of the proposed control method is demonstrated by experiments. Comparisons of the existing control method are carried out to show the superior performance of CoComC, i.e., higher register accuracy, superior fluctuation attenuation performance and less waste of printing material.