Printing Pressure Uniformization Through Adaptive Feedforward Control in Roll-to-Roll Printing Process

Printed electronics is a technology for making electronic devices using functional ink and flexible material film. The roll-to-roll printed electronic process is a next-generation process that is environmentally friendly and mass-productive at low cost. However, if the printing pressure between two rolls cannot be made uniform in the roll-to-roll process, it is difficult to commercialize the printed electronics due to the degradation of the printing quality. Previous study has proposed a method to select the initial condition that minimizes the printing pressure change using shape information of the roll and minimized printing pressure is verified by using the load cell signal. However, repetitive pressure errors that occur as the roll rotates require printing pressure uniformization control. In this paper, the printing pressure is predicted by using the shape information of the roll, and adaptive feedforward control is performed based on the predicted result to uniformize the printing pressure. Then, the experimental results are verified using a load cell signal.