Finite-time velocity sensorless integral sliding mode control for roll-to-roll systems under matched disturbances

Area of Science:

• Control Systems Engineering
• Manufacturing Process Optimization
• Nonlinear Dynamics

Background:

• Roll-to-Roll (R2R) systems face productivity and quality issues due to model uncertainty and external interference.
• Achieving consistent high performance in industrial R2R processing is a significant challenge.
• Economic losses are substantial due to reduced output quality and productivity.

Purpose of the Study:

• To propose a novel control strategy for enhancing the performance of industrial Roll-to-Roll (R2R) systems.
• To address challenges posed by model uncertainty and external interference in R2R manufacturing.
• To ensure consistently high tracking performance for critical system parameters like transport speed and material surface tension.

Main Methods:

• Integration of a finite-time integral terminal sliding mode controller with a finite-time extended state observer.
• Development of a three-component observer for dual estimation of velocity states and disturbances/uncertainties in unwinder, guide, and rewinder rolls.
• Application of Lyapunov stability theory to prove the ultimate uniform boundedness of observational errors and the stability of the overall control framework.

Main Results:

• The proposed controller demonstrates high tracking performance for transport speed and material surface tension.
• Observational errors are proven to be ultimately uniformly bounded, ensuring reliable state and disturbance estimation.
• The integrated control framework, combining the observer and controller, is validated for stability using Lyapunov theory.

Conclusions:

• The finite-time integral terminal sliding mode control with a finite-time extended state observer offers a robust solution for industrial R2R systems.
• The proposed method effectively mitigates the impact of model uncertainty and external interference, improving system performance.
• Comparative analyses confirm the superior efficiency of the proposed control strategy over existing nonlinear controllers.