近空间可变翼飞行器多模态切换控制研究

发布时间：2018-10-11 11:52

【摘要】：近空间飞行器(Near Space Vehicle,NSV)工作在20~100km的近空间区域,具有高效费比、长滞空时间、高分辨率、强机动性等优点,因此目前对近空间飞行器的研究工作受到世界各军事强国的高度重视。近空间可变翼飞行器(Near Space Morphing Vehicle,NMV)不仅具有强非线性、激烈快时变、强耦合以及严重不确定性的特点,而且还存在小翼伸缩变化问题,因此对近空间可变翼飞行器各模态的控制以及模态切换控制的研究都是极具挑战性的工作。本文针对近空间可变翼飞行器的非线性模型建立、不同飞行模态以及小翼状态下的飞行控制、不同飞行模态和小翼伸缩变化的切换控制等问题进行研究。具体研究内容如下:首先,根据国内外公布的近空间飞行器的模型的数据,结合可变翼的特点建立具有伸缩小翼的近空间可变翼飞行器非线性模型。由于飞行器飞行环境的复杂多变的特性和不同模态飞行任务的差异,建立了大气环境模型和不同模态的发动机推力模型,并分析飞行器的开环特性,为飞行器的飞行控制和切换控制的研究奠定坚实的基础。其次,由于近空间飞行器飞行包络大,不同飞行模态飞行器的特性和控制要求都具有一定的差异。因此,基于飞行任务的差异和小翼状态对近空间可变翼飞行器的模态进行划分,分析各模态约束条件以及小翼状态对气动力和力矩的影响。考虑到滑模控制方法在处理不确定性问题的优点以及抖振的缺点,针对反馈线性化后的等效模型,提出双幂次趋近律滑模控制方法,并设计爬升和巡航模态的飞行控制器。本文首先从理论上证明双幂次趋近律滑模控制方法的稳定性,然后通过仿真验证证明该方法对不同飞行模态控制的有效性和鲁棒性。然后,考虑到模态切换时飞行状态会发生突变,极易造成飞行器的不稳定。因此,针对近空间可变翼飞行器爬升/巡航模态的切换过程,分析直接切换的控制效果,说明设计切换控制律的必要性。考虑到滑模控制方法具有较好的鲁棒性,提出一种基于惯性环节的双幂次趋近律滑模切换控制算法,通过数值仿真分析该方法与传统的惯性环节切换控制方法的优劣。最后,鉴于本文研究对象的特殊性,分析小翼不同状态对飞行控制的影响,对不同小翼状态下的控制系统进行研究。由于小翼状态的变化导致气动参数的变化,因此将基于惯性环节的双幂次趋近律滑模切换控制算法应用到小翼收回/伸出的切换过程,数值仿真验证说明了该方法具有较好的控制效果以及良好的鲁棒性。综上所述,本文针对近空间可变翼飞行器不同模态的飞行控制、飞行模态的切换以及小翼伸缩切换等问题进行研究,提出一种新型的切换控制算法,保证模态切换过程的稳定和平滑。
[Abstract]:The near space vehicle (Near Space Vehicle,NSV) works in the near space area of 20~100km. It has the advantages of high efficiency cost ratio, long lag time, high resolution and strong maneuverability. Therefore, the research work of near space vehicle has been attached great importance to by the military powers all over the world. Near-space variable wing aircraft (Near Space Morphing Vehicle,NMV) not only has the characteristics of strong nonlinearity, intense and fast time-varying, strong coupling and serious uncertainty, but also has the problem of small wing expansion and expansion. Therefore, it is very challenging to study the modal control and modal switching control of the near space variable wing aircraft. In this paper, the nonlinear model establishment, flight control under different flight modes and wings, and switching control for different flight modes and wing expansion changes are studied in this paper. The specific research contents are as follows: firstly, according to the data of the model of the near space vehicle published at home and abroad, the nonlinear model of the near space variable wing with the telescopic wing is established according to the characteristics of the variable wing. Because of the complex and changeable characteristics of the flight environment and the differences of different modes of flight missions, the atmospheric environment model and the engine thrust model of different modes are established, and the open-loop characteristics of the aircraft are analyzed. It lays a solid foundation for the research of flight control and switching control of aircraft. Secondly, because of the large flight envelope, the characteristics and control requirements of different flight modes are different. Therefore, based on the mission difference and the small wing state, the modal of the near space variable wing aircraft is divided, and the influence of each modal constraint condition and the small wing state on the aerodynamic force and torque is analyzed. Considering the advantages of sliding mode control (SMC) in dealing with uncertain problems and the disadvantages of buffeting, a double power approach law sliding mode control method is proposed for the equivalent model of feedback linearization, and flight controllers for climbing and cruising modes are designed. In this paper, the stability of the sliding mode control method is proved theoretically, and then the effectiveness and robustness of the method for different flight modes are proved by simulation. Then, considering the sudden change of flight state during mode switching, it is easy to cause instability of the aircraft. Therefore, in view of the switching process of climbing / cruising mode of the near space variable wing aircraft, the control effect of direct switching is analyzed, and the necessity of designing switching control law is explained. Considering the robustness of the sliding mode control method, a sliding mode switching control algorithm based on the inertial link is proposed. The advantages and disadvantages of this method and the traditional inertial link switching control method are analyzed by numerical simulation. Finally, in view of the particularity of the research object, the influence of different states on flight control is analyzed, and the control system under different wing states is studied. Because the aerodynamic parameters change due to the change of the wing state, the double power approach law sliding mode switching control algorithm based on the inertia link is applied to the transfer process of the wing retraction / extension. Numerical simulation shows that the method has good control effect and good robustness. To sum up, a new switching control algorithm is proposed in this paper, which focuses on the flight control, flight mode switching and flanking switching of the near-space variable wing aircraft. The mode switching process is stable and smooth.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：V249.1

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