Multirotor aerial vehicles are versatile flying robots that perform hovering, vertical take-off and landing, and aggressive maneuvers in a 3D environment. Due to their underactuated nature, the aerial vehicles' position and orientation cannot be controlled independently. For this reason, most of the quadrotors' tasks involved position tracking or regulation tasks. This paper focuses on the position-tracking problem of quadrotors using the reduced orientation of the vehicle, meaning that only two degrees of freedom of the robot's orientation are controlled. We propose an almost global exponential reduced attitude control law that aligns the aerial robot's thrust direction with the desired force that drives the robot along the desired position trajectory. For the translational subsystem, we propose a dynamic control law that drives the position and velocity of the quadrotors asymptotically to the desired trajectories. The proposed attitude control law is computationally simple, and thus, it is suitable to run on board. Finally, we provide experimental results performed on a low-cost quadrotor and a comparison study with a full-attitude controller to illustrate the performance and advantages of the proposed control laws.

中文翻译：

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四旋翼飞行器的位置和降低姿态轨迹跟踪控制：理论与实验


多旋翼飞行器是多功能飞行机器人，可在 3D 环境中执行悬停、垂直起飞和降落以及激进机动。由于飞行器的驱动不足性质，无法独立控制飞行器的位置和方向。出于这个原因，四旋翼飞行器的大部分任务都涉及位置跟踪或调节任务。本文重点介绍了使用车辆减少方向的四旋翼飞行器的位置跟踪问题，这意味着只控制机器人方向的两个自由度。我们提出了一个几乎全局的指数降阶姿态控制定律，该定律将空中机器人的推力方向与驱动机器人沿所需位置轨迹的所需力对齐。对于平移子系统，我们提出了一个动态控制定律，该定律将四旋翼的位置和速度渐近地驱动到所需的轨迹。所提出的姿态控制定律在计算上很简单，因此适合在船上运行。最后，我们提供了在低成本四旋翼飞行器上进行的实验结果以及与全姿态控制器的比较研究，以说明所提出的控制律的性能和优势。