一种双倾斜式全驱动六旋翼无人机的建模与控制

Modeling and control of a fully-actuated hexarotor with double-tilted rotors

常规旋翼无人机大都采用共线设计,只能产生竖直方向的推力,极大地限制了旋翼无人机在涉及物理交互任务时的应用。针对此问题,研究了一种双倾斜式全驱动六旋翼无人机,采用旋翼转轴非共线的设计方法,可以实现位置与姿态的独立控制。提出了一种抑制抖振的改进型积分滑模控制器,并与PID控制器、积分反演控制器和传统积分滑模控制器进行对比。仿真结果表明,所提出的改进型积分滑模控制器能够实现旋翼无人机位置与姿态的独立控制,并能够有效克服自身模型参数的不确定性以及外部的风场扰动完成定点悬停与复杂的轨迹跟踪。实物样机实验结果表明,该设计的全驱动旋翼无人机在长距离横向运动时能够保持水平姿态,俯仰角和滚转角误差控制在±2°以内。

Conventional rotor unmanned aerial vehicles(UAV)mostly adopt the collinear design.It can only generate thrust in the vertical direction,which greatly limits its application in the physical interaction tasks.To solve this problem,this article studies a fully-actuated hexarotor with double-tilted rotors.It can realize independent control of position and attitude by adopting the design method of non-collinear rotor shaft.An improved integral sliding mode(ISM)controller with chattering suppression is proposed.It is compared with the PID controller,integral backstepping(IB)controller and traditional integral sliding mode controller.Simulation results show that the proposed improved ISM controller can achieve the independent control of the position and attitude of the rotor UAV,which can effectively overcome the uncertainty of its own model parameters and the external wind field disturbance to complete the fixed-point hovering and complex trajectory tracking.Experimental results of the implemented prototype show that the designed fully-actuated rotor UAV can maintain the horizontal attitude during the long-distance lateral motion.The pitch and roll angle errors are controlled within two degrees.