A nonlinear design method of robust PI control by using adaptive backstepping control for web winding system of reversible cold rolling mill.

The metal manufacturing industry employs the reversible cold rolling mill, which is a machine used to process and shape various metal products such as steel sheets, aluminum sheets, and copper sheets. High accuracy control of web velocity and web tension is essential in the manufacturing process for preventing the web from bending or breaking during the entire manufacturing process. In this work, we introduce a control law design method using PI control with unknown parameters for the web winding system to ensure that the final product will not be affected by deformation or breakage. In the first step of the adaptive backstepping procedure, the integral action is obtained by adding the integral of the tracking error to the error considered. The stability of the control design is ensured by the Lyapunov stability theorem. It verifies that the trajectory dynamics are asymptotically stable. To illustrate the effectiveness and performance of the proposed controllers, simulation studies using the MATLAB/Simulink environment are presented. [ABSTRACT FROM AUTHOR]