Tension Regulation of Roll-to-roll Systems with Flexible Couplings

Web transport system can be found in various applications, such as paper manufacture and printing process. Due to elasticity of web materials and changing in roll inertia, the challenge regarding tension control is still increasing. Moreover, the web handling system is connected to driving motor through limited stiffness shafts. Non-rigid nature of the shafts induces un-wanted vibration to the system, making the tension control complicated. The paper presents a control solution for a roll-to-roll web-transport system with flexible couplings. The web-transport system coupled with motors through non-rigid driving shaft is formed as a two-mass system. In this paper, the thickness of web material is assumed to be conscious in order to achieve a simple calculation of roll inertia momentum. Based on a backstepping control technique, control laws for unwinding and rewinding roll are derived. The control schemes ensure a linear velocity and tension tracking performance of the system. Extensive numerical simulations are carried out to verify the feasibility of the proposed control strategy.