一种带有观测器的高速飞行器预测滑模控制方法

A Predictive Sliding Mode Control Method for Hypersonic Vehicle with Observer

针对高速飞行器巡航段的速度和高度指令跟踪控制问题,提出了一种基于线性扩张状态观测器的预测滑模控制方法。首先,对飞行器模型进行反馈线性化,在此基础上设计了速度通道和高度通道的跟踪滑模面,利用Taylor展开对跟踪滑模面进行预测;其次,利用优化性能指标推导出预测滑模控制律,使用Lyapunov稳定性理论证明其稳定性,所设计控制律可避免使用不连续切换函数,有效抑制抖振;然后,利用飞行器速度、高度和俯仰角的测量值,设计基于反正切跟踪微分器在线估计飞行器的航迹倾角和攻角;最后,针对带有飞行器状态估计误差以及飞行器参数偏差的动力学系统,将这些内外干扰视为系统“总扰动”,通过线性扩张状态观测器对其进行观测并加以补偿,通过对比仿真验证了所提方法的有效性。

The predictive sliding mode control(PSMC) method based on linear extended state observer(LESO) is proposed to solve the speed and altitude command tracking problem of hypersonic vehicle in the cruise phase. Firstly, the vehicle model is linearized by feedback, and then the tracking sliding mode surfaces of velocity channel and altitude channel are designed and Taylor expansion is used to predict the tracking sliding mode surfaces. Secondly, the predictive sliding mode control law is derived from the optimized performance index, and its stability is proved by Lyapunov stability theory. The designed control law can avoid using discontinuous switching functions and effectively suppress chattering. Then, based on the measured values of aircraft speed, altitude and pitch angle, an arctangent tracking differentiator is designed to estimate the aircraft’s track inclination and angle of attack online. Finally, Regarding dynamic systems with vehicle state estimation errors and vehicle parameter deviations, these internal and external disturbances are regarded as “total disturbances” of the system, which are observed and compensated by using a linear extended state observer. The effectiveness of the proposed method is verified by comparative simulation.