Control of Fluctuational Tension in Roll-to-Roll Manufacturing Systems under Acceleration and Deceleration Conditions

The roll-to-roll system is widely known for its ability to achieve high-speed mass production through continuous web transfer during printing processes. Typically, this system comprises multiple driven rolls and idle rollers that rotate alongside the transported web. In a roll-to-roll system, the influence of the moment of inertia between the driven rolls is more significant during acceleration and deceleration than at a constant speed. Consequently, the difference in the moment of inertia between two driven rolls within the span can result in variations in the linear speed. Such speed differences between the driven rolls generate significant tension disturbances in the roll-to-roll system, which can cause unintended pattern degradation if excessive. This study presents the development of a feed-forward tension control method designed to compensate for the difference in the moment of inertia, aimed at minimizing tension disturbances during deceleration and acceleration. The experimental results demonstrated a 75.8% improvement in tension control performance after compensating for tension disturbances based on the difference in the moment of inertia between the driven rolls. This performance enhancement enables the mass-produced pattern to achieve reduced and more uniform resistance, which is a critical requirement for the highly promising roll-to-roll green manufacturing processes.