Dynamic event-triggered fault-tolerant control of rigid spacecraft with prescribed performance

Area of Science:

• Aerospace Engineering
• Control Systems Theory
• Robotics

Background:

• Spacecraft attitude control is crucial for mission success.
• Actuator faults, parameter uncertainties, and environmental disturbances pose significant challenges.
• Existing control methods often struggle with rapid convergence and disturbance rejection.

Purpose of the Study:

• To develop a novel fixed-time disturbance observer (DO)-based dynamic event-triggered fault-tolerant control (DETFTC) framework.
• To achieve prescribed performance for rigid spacecraft attitude tracking under various uncertainties and faults.
• To minimize control updates while ensuring rapid and precise attitude stabilization.

Main Methods:

• A fixed-time disturbance observer (DO) is proposed to accurately estimate lumped perturbations.
• A dynamic event-triggered fault-tolerant control (DETFTC) strategy is designed to optimize control signal transmissions.
• Integration of fixed-time performance functions with barrier Lyapunov functions ensures bounded-time convergence of tracking errors.

Main Results:

• The proposed framework guarantees practical fixed-time stability for all closed-loop system signals.
• Attitude tracking errors are constrained within predetermined boundaries.
• Zeno behavior is effectively excluded, ensuring practical implementation.

Conclusions:

• The developed DETFTC framework with a fixed-time DO offers an effective solution for spacecraft attitude control.
• The methodology demonstrates robustness against actuator faults, parameter uncertainties, and external disturbances.
• Case studies validate the practical applicability and effectiveness of the proposed approach.