Sliding-Mode Control for Perturbed MIMO Systems With Time-Synchronized Convergence.

Area of Science:

• Control Systems Engineering
• Nonlinear Control Theory
• Robotics and Automation

Background:

• Multi-input-multi-output (MIMO) systems are prevalent in various engineering applications.
• Achieving simultaneous and synchronized convergence of all outputs in MIMO systems under disturbances is a significant control challenge.
• Existing control methods often struggle with complex dynamics and external perturbations.

Purpose of the Study:

• To introduce a novel terminal sliding-mode control (TSMC) approach for MIMO systems.
• To achieve time-synchronized convergence of all output dimensions in the presence of disturbances.
• To categorize MIMO systems into input-dimension-dominant and state-dimension-dominant for tailored controller design.

Main Methods:

• Classification of MIMO systems based on signal dimensions into input-dominant and state-dominant categories.
• Development of adaptive controllers using terminal sliding-mode designs and Lyapunov stability conditions for the input-dominant case.
• Integration of a multivariable disturbance observer with a super-twisting structure to handle system perturbations.

Main Results:

• The proposed TSMC controller ensures simultaneous convergence of all output dimensions for input-dimension-dominant systems.
• Comparative simulations demonstrate shorter output trajectories and reduced energy consumption compared to existing methods.
• For state-dimension-dominant systems, numerical examples validate the semi-time-synchronized convergence property.

Conclusions:

• The novel TSMC approach effectively addresses time-synchronized convergence in MIMO systems under disturbances.
• The controller design, incorporating a disturbance observer, enhances system performance by reducing trajectory length and energy usage.
• The study provides a robust framework for controlling complex MIMO systems with distinct dynamic characteristics.