阻力方向舵在飞翼式高空长航时无人机中的应用

根据飞翼式高空长航时无人机的风洞实验结果,分析了全机尤其是阻力方向舵的气动和操稳特性,据此采用经典方法设计了阻力方向舵的控制律,提出用阻力方向舵进行航向控制和速度控制的方案,并指出由于存在操纵耦合,有必要进行阻力方向舵和升降舵交联控制。非线性飞行仿真结果表明,阻力方向舵具有满意的航向和速度操纵能力,采用交联控制后速度响应更平稳,并可减小33的高度偏差和56的俯仰角偏差。

Exploring Utilization of Drag Rudder in Stability and Control of Flying Wing High Altitude Long Endurance(HALE)UAV

According to the wind tunnel testing of a flying wing HALE UAV,we analyze the aerodynamic,control and stability properties of this UAV equipped with drag rudder.In section 1 of the full paper,we describe the special features of such a flying wing,using the U.S.B-2 as an example.In section 2,we give Fig.2 to show that both the drag and lateral force of the flying wing increase approximately linearly with increasing deflection angle of the drag rudder,thus increasing the yawing moment.Fig.2 also shows that the nonlinear change of lift subsequently brings about the nonlinearities respectively of the pitch moment and the roll moment of the flying wing.Also in section 2,we give Fig.3 to demonstrate that at the small angle of attack,the aerodynamic coefficient does not change appreciably,while at the large angle of attack,it changes remarkably and the pitch moment,in particular,decreases sharply.In section 3,we design the control law of the drag rudder.In doing so,we propose controlling the direction and velocity of the flying wing with the drag rudder.We point out that the deflection of the drag rudder produces rather big pitch moment.Therefore,it is necessary to use both the drag rudder and the elevator to perform interactive control.In section 4,we carry out the computer simulation of the drag rudder utilization.The simulation results,shown in Figs.5 through 7,indicate preliminarily that the drag rudder can satisfactorily control the direction and velocity of the flying wing and that the interactive control has stable response speed,with the altitude error reduced by 33% and the pitch angle error by 56% respectively.