Simulation parameters.

This paper addresses the problem of predefined-time attitude tracking control for rigid spacecraft subject to external disturbances and unknown inertia parameters. First, a predefined-time non-singular sliding surface is designed to ensure that the closed-loop system converges within a predefined time. Second, to tackle the unwinding problem inherent in quaternion-based modeling, a potential function is introduced in the controller design to guarantee anti-unwinding performance even outside the sliding surface. The proposed controller not only suppresses chattering but also ensures both anti-unwinding behavior and predefined-time convergence. Then, an event-triggered mechanism is developed to reduce communication burden while avoiding Zeno behavior. The proposed control method can make the attitude tracking error converge to an arbitrary predefined residual set. Finally, simulation results verify the effectiveness of the proposed method.

本文针对受外部扰动与未知惯性参数影响的刚性航天器预设时间姿态跟踪控制问题展开研究。首先，设计预设时间非奇异滑模面，确保闭环系统可在预设时间内收敛。其次，为解决基于四元数（quaternion）建模固有的解旋问题（unwinding problem），在控制器设计中引入势函数，即便在滑模面（sliding surface）之外也能保证抗解旋性能。所提出的控制器不仅可抑制抖振，同时能够确保抗解旋行为与预设时间收敛特性。随后，提出事件触发机制（event-triggered mechanism）以降低通信负载，同时规避芝诺行为（Zeno behavior）。所提控制方法可使姿态跟踪误差收敛至任意预设残差集。最后，仿真结果验证了所提方法的有效性。