This work presents a novel control strategy for the trajectory tracking control of the quadrotor unmanned aerial vehicle (UAV) with parameter uncertainties and external unknown disturbances. As a stepping stone, two fixed-time extended state observers (ESOs) are proposed to estimate the external disturbances and/or the parameter uncertainties for the position and attitude subsystems, respectively. Then, the fast terminal sliding mode-based improved dynamic surface control (DSC) approaches are developed. To eliminate the problem of “explosion of complexity” inherent in backstepping method-based controllers, the finite-time command filters and an error compensation signals are used in the design of the dynamic surface controllers. Subsequently, the practically finite-time stability of the closed-loop tracking system is guaranteed by utilizing the proposed control scheme. The simulation results are obtained to demonstrate the effectiveness and fine performance of the proposed trajectory tracking control approaches.

中文翻译：

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基于扩展状态观测器的四旋翼无人机轨迹跟踪有限时间动态曲面控制

这项工作提出了一种新的控制策略，用于具有参数不确定性和外部未知干扰的四旋翼无人机（UAV）的轨迹跟踪控制。作为垫脚石，提出了两个固定时间扩展状态观测器（ESO）来分别估计位置和姿态子系统的外部干扰和/或参数不确定性。然后，开发了基于快速终端滑模的改进动态表面控制（DSC）方法。为了消除基于反步法的控制器固有的“复杂度爆炸”问题，在动态表面控制器的设计中使用了有限时间命令滤波器和误差补偿信号。随后，通过利用所提出的控制方案，保证了闭环跟踪系统的实际有限时间稳定性。仿真结果证明了所提出的轨迹跟踪控制方法的有效性和优良性能。