A high-precision prescribed-time guidance law is developed for a quadrotor to accomplish precise path following at predesigned time T. Firstly, a new control structure is proposed for a quadrotor to perform fixed-velocity back-to-turn flying mode by introducing four controllers, which can realize a non-sideslip and bank-to-turn flight scheme just like a fixed-wing unmanned aerial vehicle. Then, prescribed-time guidance law is presented based on fixed-velocity back-to-turn flying mode via combining sliding mode control with a compensation function p t to improve tracking precision of conventional methods. Compensation function p t is designed to make state error achieve convergence at prescribed time exactly. Meanwhile, global sliding mode is established to enhance robustness of the system. Then, the stability and characteristic of prescribed-time convergence are proved strictly. Finally, simulations with a 6-degree-of-freedom quadrotor model are carried out to demonstrate the effectiveness and superiority of prescribed-time guidance law by comparing with traditional guidance law.

中文翻译：

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四旋翼高精度规定时间轨迹跟踪

提出了四旋翼高精度定时制导律，在预定时间T完成精确路径跟踪。首先，提出了四旋翼定速返航飞行模式的新控制结构，引入四个控制器，可以像固定翼无人机一样实现无侧滑和倾斜转弯的飞行方案。然后，通过将滑模控制与补偿函数pt相结合，提出了基于定速返航飞行模式的规定时间制导律，以提高传统方法的跟踪精度。补偿函数 pt 旨在使状态误差准确地在规定的时间达到收敛。同时，建立全局滑模以增强系统的鲁棒性。然后，严格证明了规定时间收敛的稳定性和特性。最后，通过六自由度四旋翼模型进行仿真，通过与传统制导律的对比，验证了规定时间制导律的有效性和优越性。