变体飞行器LPV建模与内外环鲁棒控制

LPV modeling and robust control of inner and outer loops for morphing aircraft

变体飞行器能够根据复杂的任务、环境等信息自适应地改变本体气动布局,从而达到特定飞行条件下的最优性能。针对一类翼展可自由伸缩的飞行器,研究了基于线性变参数(Linear Parameter Varying,LPV)系统的变体飞行器内外环鲁棒控制问题。采用Jacobian线性化方法建立变体飞行器LPV模型,将双环控制技术拓展到LPV模型中,采用线性二次型最优控制法(Linear Quadratic Regulator,LQR)设计内环控制器,并引入粒子群优化算法(Particle Swarm Optimization,PSO)求出二次型系统的最优权值矩阵,在保证飞行器速度、高度稳定的基础上,有效降低了系统的超调量,提高了控制器的收敛速度。外环加入鲁棒H∞状态反馈控制器,并将输入变量扩展到系统状态中,进一步解决了变体过程中导致的舵偏指令过大的问题,保证了飞行器在变形过程中能够平缓过渡,并证明了该控制器满足二次Lyapunov稳定的线性矩阵不等式(Linear Matrix Inequality,LMI)条件。仿真结果表明:当存在一定的外部干扰时,所设计的内外环鲁棒控制器能够保证飞行器在整个形变过程中具有良好的稳定性和鲁棒性。

According to complex tasks,environment and other information,the morphing aircraft could adaptively change its aerodynamic layout of the body to achieve optimal performance under specific flight conditions.For a type of aircraft model with a free-retractable wingspan,the robust control of the inner and outer loops of a morphing aircraft based on a linear parameter varying(LPV) system is studied.A LPV model of the morphing aircraft is developed based on the Jacobian linear method.The dual-loop control technology is extended to the LPV model.The inner-loop controller is designed by using the linear quadratic regulator(LQR) method,and the particle swarm optimization(PSO) algorithm is used to obtain the optimal weight matrix of the quadratic system,which can effectively reduce the overshoot of the system and improve the convergence speed of the controller on the basis of ensuring the stability of the speed and height of the aircraft.A robust H∞state feedback controller is added to the outer loop,and the input variables are extended to the system state,which further solve the problem of excessive rudder deflection commands caused by the deformation process,ensuring that the aircraft can transition smoothly during the deformation process,and proving that the controller sufficiently satisfies the quadratic Lyapunov stable linear matrix inequality(LMI) condition.The simulation results illustrate that when there is a certain external disturbance,the designed inner and outer loop controller can assure good stability and robustness in the entire deformation process of the aircraft.