中文摘要：

针对存在外部干扰的刚体航天器姿态控制问题，提出一种有限时间姿态稳定控制器．采用修正罗德里格参数描述航天器姿态，基于齐次性理论与方法和一个新颖饱和函数，设计一类新颖航天器有限时间姿态稳定控制器，并利用饱和函数保证控制力矩受限．利用Lyapunov理论证明了所设计控制器能够对闭环系统在无干扰的情况下有限时间内达到稳定，且在有干扰的情况下达到渐近稳定．最后，将提出的算法应用于刚体航天器姿态稳定控制中，仿真结果验证了方案的有效性和可行性，在完成有限时间姿态稳定控制的同时，也能保证控制输出满足受限的要求．

英文摘要：

In this paper, a novel finite-time control scheme is investigated for a rigid spacecraft with attitudes represented by the modified Rodrigues parameters under external disturbances. Firstly, a new saturation function is presented so that the control torques saturation constraint can be taken into account explicitly. Then a novel finite-time attitude stabilization control scheme for a rigid spacecraft is proposed based on the homogeneous method using the saturation function. Lyapunov stability analysis shows that the resulting closed-loop attitude system is proven to be stable in finite time without disturbances, and asymptotically stable with disturbances. Finally, numerical simulation examples are also presented to demonstrate that the control strategy developed is feasible and effective, and able to robust against to external disturbance under limited saturation values.