Multicontroller-Based Fault-Tolerant Control for Uncertain High-Order Sub-Fully Actuated Systems.

Area of Science:

• Control Systems Engineering
• Nonlinear Dynamics
• Fault-Tolerant Control

Background:

• Fully Actuated Systems (FAS) offer powerful nonlinear control but face challenges in sub-FAS stabilization due to control singularity.
• Actuator faults (multiplicative and additive) and nonlinear uncertainties complicate the control of high-order sub-FASs.

Purpose of the Study:

• To develop a novel multicontroller-based fault tolerance method for global stabilization of uncertain high-order sub-FASs with actuator faults.
• To address and overcome the control singularity issue inherent in sub-FAS stabilization.

Main Methods:

• A high-order nonlinear system model incorporating multiplicative and additive actuator faults was developed.
• The state space was analytically divided into regions using linear singular set and singularity function concepts.
• Three distinct control strategies (FAS-based stabilizing, singularity-avoid tracking, singularity-free switching) were designed based on initial system states.

Main Results:

• The proposed method effectively overcomes control singularity and achieves global stabilization for uncertain sub-FASs.
• The closed-loop response of the faulty system demonstrated ultimate uniform boundedness under all considered scenarios.
• A numerical example validated the effectiveness of the developed fault-tolerant control strategies.

Conclusions:

• The novel multicontroller-based fault tolerance method provides a robust solution for stabilizing uncertain high-order sub-FASs with actuator faults.
• The analytical division of the state space and tailored control strategies successfully manage control singularity.
• The findings contribute to advancing fault-tolerant control for complex nonlinear systems.