高超声速飞行器抗干扰反步滑模控制

Disturbance rejection sliding mode control of hypersonic vehicle based on backstepping method

针对存在参数不确定及外部扰动下的高超声速飞行器轨迹跟踪控制问题,研究了一种基于反步法的抗干扰滑模控制设计方法.将非线性高超声速飞行器动力学模型表达为严反馈形式分步进行设计.采用滑模控制方法进行每步的控制器设计,并提出采用扩展状态观测器(ESO,Extended State Observer)方法实现对参数不确定及外部扰动产生的内外干扰进行估计,继而在控制中补偿.扩展状态观测器能保证对干扰的估计收敛到真值附近的邻域内,从而能够保证较好的补偿效果.通过0.5°附加干扰攻角和25%的气动参数偏差下的非线性高超声速飞行器动力学模型仿真结果验证了该抗干扰滑模控制方案对内外干扰的抑制效果和闭环系统良好的跟踪性能.

A kind of disturbance rejection sliding mode control based on backstepping method was studied for trajectory tracking control problem of hypersonic flight vehicle in the presence of uncertain parameters and external disturbances. The nonlinear hypersonic vehicle dynamics model was translated into the strict feedback form under reasonable hypothesis. Slidingmode control was used in the design of each step. The parameters uncertainty and external disturbances were regarded as disturbance to the system. Directed at the disturbances problem, the estimate method using extended state observer was put forwards. The disturbances were compen sated in the controller based on the value estimated. The estimate value of disturbance from extended state ob server was in a small neighborhood of the true value, so that the compensating effect can be guaranteed. The simulation based on the nonlinear model under 0.5° additional angle and 25% aerodynamic coefficient offset validates the disturbances rejection ability and good tracking performance of the closed loop system.