State Feedback Decoupling Control of Web Tension, Velocity and Lateral Displacement in Unwinding System

The coupling and control of the web tension and lateral displacement is the key problem in flexible high-precision roll-to-roll manufacturing process. The web tension and lateral displacement are modeling independently with distributed control in current research, which is hard to solve the coupling between the web tension, velocity and lateral displacement for the reason of the model uncertainties, such as time varying radius of the unwinding roll, velocity variations, and so on. To solve the above problems, this paper establishes a three inputs and three outputs coupling model of an extended unwinding system with three axes. A state feedback decoupling control method with pole placement is presented to decouple of the web tension, velocity, and lateral displacement. The transient response of the decoupled system is achieved with pole placement method based on integral of time multiplied by absolute error (ITAE) optimal principles. This approach achieves dynamic decoupling of the web tension, velocity and lateral displacement of the unwinding system. The simulation results show well performance of the decoupled system.