近空间可变翼飞行器主动控制技术研究

发布时间：2018-06-22 11:42

本文选题：近空间飞行器 + 主动控制技术　；参考：《南京航空航天大学》2016年硕士论文

【摘要】：近空间可变翼飞行器具有大飞行包络和高空高超声速飞行的能力,这些特点存在的同时也带来了更多的研究难点。飞行器高超声速飞行时气动焦点会大幅度后移,将产生很大的稳定裕度,形成很大的负俯仰力矩,需要尾翼提供抬头俯仰力矩以平衡。一方面机翼升力除了要与飞行器重量平衡,还要平衡尾翼的负向升力,使总升力减少;另一方面飞行器高速飞行段的机动性能也因为稳定裕度大大增加而变坏。同时本文研究的近空间可变翼飞行器要求实现自主水平起降,然而由于其采用大后掠翼细长比结构,低速飞行过程时升力系数较常规飞行器明显偏小,将严重影响飞行器起飞性能。针对上述问题,本文提出采用放宽静稳定性技术改善近空间可变翼飞行器升力特性不足、高速机动性能不佳的问题,采用直接力技术解决飞行器起飞性能不佳的问题。本文的主要研究内容包括:(1)定性和定量的分析放宽静稳定性对近空间可变翼飞行器升力特性及机动性能的影响收益,定量得到在保证高速巡航段飞行器机动性能良好前提下需要放宽的静稳定度,并分析实现放宽指定静稳定度的工程实现方法,为工程实现提供解决思路。(2)放宽静稳定性后的飞行器在亚声速阶段变为静不稳定,本文分别采用基于经典反馈的线性控制方法和基于动态逆-PID的非线性控制方法为亚声速飞行器设计增稳控制系统。仿真结果表示,后者能够使飞行器具有更良好的稳定性。(3)飞行器在高超声速阶段外部干扰频繁、内部变化剧烈,呈现严重的非线性特性。本文利用回馈递推方法在处理非线性问题上的独特优越性,设计基于回馈递推的智能非线性控制器,并用其对放宽静稳定后的飞行器在高超声速段进行跟踪控制,仿真结果说明控制器具有良好的跟踪性能和鲁棒性能。(4)本文最后定量研究采用矢量喷管与鸭翼协同配合产生直接力对改善近空间可变翼飞行器水平起飞性能的收益。仿真结果表明,该方法明显改善了飞行器的起飞性能。
[Abstract]:Near-space variable wing aircraft has the capability of large flight envelope and hypersonic flight at high altitude. These characteristics also bring more research difficulties. During hypersonic flight, the aerodynamic focus will move backward by a large margin, which will produce a large stability margin, and form a large negative pitch moment, which requires the tail wing to provide a lift pitch moment to balance. On the one hand, the lift of the wing must be balanced with the weight of the aircraft, but also the negative lift of the tail should be balanced to reduce the total lift. On the other hand, the maneuverability of the high-speed flight section of the aircraft is also deteriorated because of the increase of the stability margin. At the same time, the near-space variable wing aircraft studied in this paper requires autonomous horizontal take-off and landing. However, the lift coefficient in low speed flight process is obviously smaller than that of conventional aircraft because of its large swept wing slenderness ratio structure. Will seriously affect the aircraft takeoff performance. Aiming at the above problems, this paper puts forward the problem of using relaxation static stability technology to improve the lift characteristics of near space variable wing aircraft and poor performance of high speed maneuverability, and using direct force technology to solve the problem of poor take-off performance of aircraft. The main contents of this paper are as follows: (1) qualitative and quantitative analysis of the impact of relaxation of static stability on lift characteristics and maneuverability of near-space variable wing aircraft; The static stability degree which needs to be relaxed under the premise of good maneuverability of the aircraft in high-speed cruising section is obtained quantitatively, and the engineering realization method to realize the relaxation of specified static stability degree is analyzed. It provides a solution for engineering implementation. (2) after relaxation of static stability, the aircraft becomes static instability in the subsonic phase. In this paper, the linear control method based on classical feedback and the nonlinear control method based on dynamic inverse pid are used to design the stability enhancement control system for the subsonic vehicle. The simulation results show that the latter can make the aircraft have better stability. (3) the external interference of the aircraft in hypersonic phase is frequent, the internal changes are severe, and the aircraft presents serious nonlinear characteristics. In this paper, an intelligent nonlinear controller based on feedback recursion is designed based on the unique superiority of feedback recursive method in dealing with nonlinear problems, and it is used to track and control the aircraft at hypersonic speed after relaxation of static stability. The simulation results show that the controller has good tracking performance and robust performance. (4) in the last part of this paper, the direct force generated by the coordination of vector nozzle and duck wing is quantitatively studied to improve the horizontal take-off performance of the near-space variable wing aircraft. The simulation results show that this method can improve the take-off performance of the aircraft.
【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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