基于模糊控制的高超声速飞行器二阶滑模姿态控制

Second-order sliding mode attitude control based on fuzzy control for hypersonic vehicle

考虑高超声速飞行器飞行过程中气动参数变动导致的不确定,将模糊控制与二阶滑模控制相结合,形成自适应模糊二阶滑模控制器,用于控制高超声速飞行器姿态的飞行系统中.依据奇异摄动理论,设计快速和慢速双闭环系统控制角速率和姿态角.设计二阶滑模控制器用于有效地衰减抖振,同时对姿态角指令实现准确和快速跟踪.采用自适应模糊逻辑逼近高超声速飞行器动力学和运动学模型中的不确定部分,以对控制器进行有效补偿,基于Lyapunov稳定性理论,推导模糊规则参数的自适应律,确保整个闭环控制系统的稳定.仿真结果表明,所提出的高超声速飞行器的自适应模糊滑模控制系统能够有效抑制气动参数摄动的影响,对姿态角指令有较好的跟踪性能.

Considering the uncertainties caused by aerodynamic parameters variation during flight, fuzzy control and second-order sliding mode control are combined to constitute fuzzy sliding mode controllers for attitude control of hypersonic vehicles. According to the singular perturbation theory, the fast and slow double closed loop syetem is designed to control angle velocity and attitude angles. The second-order sliding mode controller is designed, so as to attenuate the chattering phenomena and achieve enhanced tracking accuracy with a finite-time convergence. Then the uncertain part of the hypersonic vehicle model is approximated by the adaptive fuzzy logic to compensate for the controller effectively. Based on the Lyapunov stability theory, the adaptive law of fuzzy rule parameters is deduced and the stability of the entire control system is proved. The simulation results show that the fuzzy sliding mode control of the hypersonic vehicle can restrain the influence of the change of aerodynamic parameters effectively and track the expected attitude angle quickly and accurately.