This paper presents the trajectory planning of an under-actuated quadcopter unmanned aerial vehicle. To control the complete structure of the rotorcraft, the main model is divided into two sub-models, namely inner model and external model. The inner model is for the attitude control model controlled by the sliding mode controller and the outer model is altitude control model governed by the extended state observer. The quadrotor unmanned aerial vehicle is a type of multivariable, multi-degree-of-freedom and nonlinear in nature. Planning the trajectory of the unmanned aerial vehicle and stabilizing its flight are complex tasks because of its ability to maneuver quickly. Due to these stated issues, the tuning of this type of dynamic system is a difficult task. This paper deals with these issues by designing the aforementioned dual controller scheme. In addition, the effectiveness of the proposed controller is apparent in simulations performed in MATLAB, Simulink 2016. The designed controller shows better results and robustness than traditional controllers do.

中文翻译：

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基于扩展状态观测器的滑模控制四旋翼飞行器轨迹规划

本文介绍了欠驱动四旋翼无人机的轨迹规划。为了控制旋翼机的完整结构，主模型分为内部模型和外部模型两个子模型。内模型为滑模控制器控制的姿态控制模型，外模型为扩展状态观测器控制的高度控制模型。四旋翼无人机本质上是一种多变量、多自由度、非线性的飞行器。规划无人机的轨迹并稳定其飞行是一项复杂的任务，因为它具有快速机动的能力。由于这些陈述的问题，调整这种类型的动态系统是一项艰巨的任务。本文通过设计上述双控制器方案来解决这些问题。