An Adaptive Decoupling Register Control Method for Roll-to-Roll Printing Systems

Abstract Model-based decoupling control methods have been widely used in the register control of Roll-to-Roll (R2R) printing systems due to their advantage in dealing with couplings. While they achieve a certain decoupling effect, their registrations are influenced by the accuracy of the model and decoupling compensation. In this paper, a hybrid model is presented to calculate an appropriate compensation to eliminate the complex velocity-error relations in the R2R system, which consists of a general register error model and a data-based supplement model. Then, an adaptive decoupling control (ADC) method is proposed, in which the feedback gains are determined by solving a Riccati equation. The effectiveness of the hybrid model is validated by experiments, while the superior performance of the ADC is demonstrated by simulations. The results indicate that the hybrid model is more accurate than the general model and ADC method can rapidly reduce the register errors into a range of ±10 μm. In addition, simulated comparisons of ADC, direct decoupling proportional differential (DDPD), and improved DDPD control methods also show that the ADC owns the highest register precision and smoothest control signal.