推力矢量可倾转四旋翼自抗扰飞行控制方法

Active disturbance rejection flight control method for thrust-vectored quadrotor with tiltable rotors

中文关键词  推力矢量  可倾转旋翼  自抗扰控制器  控制分配  飞行器

英文关键词  thrust vector  tiltable rotors  active disturbance rejection controller  control allocation  aircraft

中文摘要

      针对常规四旋翼难以实现位置和姿态独立控制问题, 研究了一种具有全向推力矢量的可倾转四旋翼飞行 器系统. 为克服系统的大范围不确定性、强耦合性及外部风扰影响, 设计了基于自抗扰控制(ADRC)技术的飞行控 制器. 通过建立风扰下的系统动力学模型, 分析阵风对旋翼气动力的影响. 接着将系统解耦为六通道单回路结构并 分别设计自抗扰控制器, 引入扩张状态观测器估计系统的内外扰动, 利用非线性状态误差反馈律输出扰动补偿控 制. 在此基础上, 通过变量代换线性化控制分配矩阵, 将控制器输出直接映射到旋翼转速和倾转角. 仿真结果表明, 所设计的自抗扰飞行控制器具有良好的位置和姿态独立控制能力, 能够有效地估计和补偿紊流风扰动, 同时对系统 的部分动力失效故障有较强的鲁棒性.

英文摘要

      To solve the problem that standard quadrotors are difficult to control position and orientation independently, this paper develops a thrust-vectored quadrotor with tiltable rotors. A flight control system based on active disturbance rejection control (ADRC) technology is designed to reduce the effects of large scale uncertainties, strong coupling and external disturbances, such as varying wind. Firstly, a dynamical system of quadrotor with tiltable rotors under wind is derived, taking into account aerodynamical effects induced by crosswind. Secondly, the system is decoupled into six channels of single-loop structure, and the corresponding controller is designed separately for every channel. An extended state observer is applied to estimate the entire disturbances of the system. Subsequently, the nonlinear state error feedback law is utilized to compensate the disturbance. Thirdly, the control allocation matrix is linearized with variable substitution, so that the output of the designed controllers are directly mapped to the rotor speeds and tilting angles. Simulation results illustrate the great ability of developed active disturbance rejection flight controller to decouple control of position from control of orientation. Its effectiveness of the turbulent flow disturbance estimation and compensation, and robustness under actuator faults are also shown.