The problem of trajectory tracking of aerial vehicles with four rotors and dynamic parameter uncertainties is addressed in this article. By exploiting the cascade structure of the translational and attitude dynamics of the quadrotor, a nonlinear hierarchical adaptive control is proposed. The attitude control law is designed based on the unit quaternion, therefore, the singularities of the Euler angles and angle‐axis representation are avoided. Instead of relying on the stability properties of time‐varying cascade systems, the stability of the whole closed‐loop system is proven by an appropriate Lyapunov function. In addition, a novel method to compute the desired orientation based on the desired Cartesian trajectories and position control inputs is proposed. A set of simulations results are presented to assess the performance of the proposed adaptive controller.

中文翻译：

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基于四元数的四旋翼无人机轨迹跟踪自适应控制

本文解决了具有四个旋翼和动态参数不确定性的飞行器的轨迹跟踪问题。通过利用四旋翼的平移和姿态动力学的级联结构，提出了一种非线性的分层自适应控制方法。基于单元四元数设计了姿态控制律，因此避免了欧拉角的奇异性和角轴表示。无需依赖时变级联系统的稳定性，而是通过适当的Lyapunov函数证明了整个闭环系统的稳定性。另外，提出了一种基于期望的笛卡尔轨迹和位置控制输入来计算期望方位的新颖方法。