Robust H_∞ cost guaranteed integral sliding mode control for the synchronization problem of nonlinear tele-operation...

Area of Science:

• Robotics
• Control Systems Engineering
• Mechatronics

Background:

• Tele-operation systems face challenges with time-varying delays, disturbances, and uncertainties, impacting stability and performance.
• Existing methods often require pre-selected controller gains, limiting design flexibility.
• Accurate modeling of environment and human operator forces is crucial for robust tele-operation.

Purpose of the Study:

• To develop a robust synchronization method for tele-operation systems with time-varying delays, disturbances, and uncertainties.
• To design controllers with enhanced freedom by deriving controller gains rather than selecting them.
• To achieve less conservative stability conditions using advanced mathematical techniques.

Main Methods:

• Utilizing Linear Matrix Inequalities (LMIs) for delay-dependent sufficient conditions for integral sliding surfaces.
• Employing Wirtinger-based integral inequality and reciprocally convex combination techniques for Lyapunov-Krasovksii Functional (LKF) construction.
• Integrating the H-infinity (H∞) design method to account for environmental and human operator forces, ensuring H∞ stability.

Main Results:

• Established delay-dependent sufficient conditions for global stability of tele-operation systems with known upper bounds on time-varying delays.
• Successfully designed controller gains, increasing design degrees of freedom compared to previous approaches.
• Achieved less conservative stability conditions through advanced LKF construction techniques.
• Demonstrated the effectiveness of the combined sliding mode control and H∞ design for robust synchronization via simulation.

Conclusions:

• The proposed method effectively guarantees global stability for tele-operation systems despite time-varying delays and uncertainties.
• The integration of sliding mode control with H∞ design offers a robust and flexible solution for complex tele-operation scenarios.
• The developed techniques provide less conservative stability criteria, advancing the field of robust control for tele-operation.