Abstract: In view of the expensive and time-consuming shortcomings of traditional gain scheduling technology in many UAV applications,through the six-degree-of-freedom nonlinear model of a fixed-wing UAV,under the condition of known the aerodynamic coefficient,aircraft moment of inertia and thrust coefficient,the linear parameter varying (LPV) aircraft model is derived from the six-degree-of-freedom nonlinear model by using Jacobian linearization method.The tensor-product (TP) model transformation method is used to transform the longitudinal nonlinear parameter-dependent LPV model of UAV into TP convex polyhedron model.The robust H_∞ controller design method of gain scheduling output feedback is applied to the TP convex polyhedron model,and the robust gain predictive autopilot flight control system of conventional fixed-wing UAV is designed.A full six-degree-of-freedom aircraft simulation test of the control system is carried out in MATLAB SIMULINK environment.The results show that the closed-loop control system has good command followed,interference suppression ability,good stability and robustness in the given flight envelope,which verifies the effectiveness of the proposed flight control system.

Key words: fixed-wing unmanned aerial vehicles, nonlinear mathematical model, tensor product (TP) approach, linear parameter varying (LPV) model, robust H_∞ control

摘要： 针对传统增益调度技术在许多无人机(unmanned aerial vehicle,UAV)应用中存在的昂贵和耗时的缺点,通过某型固定翼无人机的6自由度非线性模型,在已知气动系数、飞机转动惯量和推力系数的情况下,利用雅可比线性化方法从6自由度非线性模型推导出线性变参数(linear parameter varying,LPV)飞机模型。应用张量-乘积(tensor product,TP)模型变换方法将无人机纵向非线性参数依赖的LPV模型变换为TP型凸多面体模型形式,将增益调度输出反馈鲁棒H_∞控制器设计方法应用于所得到的TP凸多面体模型,设计了常规固定翼无人机的鲁棒增益预测自动驾驶仪飞行控制系统。在MATLAB SIMULINK环境下对该控制系统进行了全六自由度的飞行器仿真试验,结果表明闭环控制系统具有良好的指令跟随性和干扰抑制能力,在定义的飞行包线范围内具有较好的稳定性和鲁棒性,验证了所提出的飞行控制系统设计方法的有效性。

关键词: 固定翼无人机, 非线性数学模型, TP方法, LPV模型, 鲁棒H_∞控制