Event-triggered adaptive predefined-time anti-unwinding attitude tracking control for spacecraft.

Area of Science:

• Aerospace Engineering
• Control Systems Theory
• Robotics

Background:

• Spacecraft attitude control is critical for mission success.
• Existing methods face challenges with external disturbances, unknown inertia, and the quaternion unwinding problem.
• Efficient communication strategies are needed to reduce data transmission load.

Purpose of the Study:

• To develop a spacecraft attitude tracking controller with predefined-time convergence.
• To address the unwinding phenomenon in quaternion-based spacecraft modeling.
• To implement an event-triggered mechanism for reduced communication burden.

Main Methods:

• Design of a predefined-time non-singular sliding surface for rapid convergence.
• Introduction of a potential function to ensure anti-unwinding behavior.
• Development of an event-triggered control mechanism to avoid Zeno behavior and reduce communication.

Main Results:

• The closed-loop system achieves convergence within a predefined time.
• The controller effectively suppresses chattering and guarantees anti-unwinding performance.
• The event-triggered mechanism reduces communication load without compromising system stability.
• Attitude tracking error converges to a predefined residual set.

Conclusions:

• The proposed control method offers robust predefined-time attitude tracking for rigid spacecraft.
• The integrated approach effectively handles disturbances, unknown parameters, and the unwinding problem.
• The event-triggered mechanism provides an efficient communication solution for spacecraft control systems.