关键词: 固定时间干扰观测器, 非奇异快速终端滑模, 抗扰控制, 重心偏移, 空中机器人

Abstract: In this paper, we propose a sliding mode control strategy based on a fixed-time disturbance observer to address the high-precision trajectory tracking control problem for air robots under compound disturbances. First, considering the coupled effects of centroid offset after target grasping and turbulent wind fields, we establish a six-degree-of-freedom dynamic model using the Newton-Euler formula and design a fixed-time convergent compound disturb-ance observer for disturbance estimation. Second, for the position control subsystem, a nonsingular fast terminal sliding mode controller based on a novel reaching law is designed, which can effectively avoid the system falling into a singular state while enhancing the system's dynamic response performance; for the attitude control subsys-tem, a hybrid control strategy integrating integral backstepping is proposed to improve the system's robustness against external disturbances. Finally, simulation comparisons are conducted to validate the effectiveness of the proposed approach.

Key words: fixed-time disturbance observer, nonsingular fast terminal sliding mode control, anti-disturbance control, barycentric offset, aerial robots