Implementation of tactical maneuvers with maneuver libraries

This study creates and combines the general maneuver libraries for fixed-wing aircraft to implement tactical maneuvers. First, the generalized maneuver libraries are established by analyzing the characteristics of tactical maneuvers required in battlefields. The 7th order polynomial is applied to both the creation of the maneuver libraries and the generation of the trajectories or flight paths for modal inputs. To track the desired trajectory, we design the Attitude Command Attitude Hold (ACAH) system and the Rate Command Rate Hold (RCRH) system using Model Following Controller (MFC). Moreover, the Line-of-Sight (LOS) guidance law is designed. In particular, the CONDUIT® is employed to optimize the gains so that the control systems meet the aircraft Handling Qualities (HQ) criteria. Finally, flight simulations are performed for the longitudinal loop, immelmann-turn, and climb-slalom-descent maneuvers to verify that tactical aggressive maneuvers are realizable via the combination of maneuver libraries. This study can contribute to the development of flight techniques for aircraft tactical maneuvers and to the revision of air force operational manuals.     

导弹靶弹弹道机动变轨通用控制指令设计

导弹进行一定强度的机动飞行,就能够提高突防能力,因而,在军事训练中需要具有末端机动变轨能力的靶弹.针对靶弹机动变轨弹道的设计问题,提出变轨通用控制指令设计形式,利用此设计可使靶弹位移与过载指令控制信号协调配合,控制靶弹实现跃升机动、蛇行机动、摆式机动和螺旋机动等变轨形式.通过仿真证明,此设计的变轨弹道通用控制指令,可以满足靶弹跃升机动、蛇行机动、摆式机动和螺旋机动等各种变轨形式的弹道设计要求.     

无人机栖落机动建模与轨迹优化

对固定翼无人飞行器栖落机动的纵向运动进行了气动特性建模与轨迹优化设计。通过运动捕捉系统测量获得试验滑翔机实时飞行数据,并结合统计学原理和平板气动理论建立了气动模型和动力学模型。针对所建立的模型采用GPOPS优化工具箱设计了栖落机动标称轨迹。优化结果表明,不同初始速度条件下执行栖落机动的空间需求不同,但最终都可以实现以相同的栖落速度落到同一位置。     

ANALYTICAL MODEL OF HELICOPTER AIRCOMBAT AND MATHEMATICINVERSE SOLUTION

ＡＮＡＬＹＴＩＣＡＬＭＯＤＥＬＯＦＨＥＬＩＣＯＰＴＥＲＡＩＲＣＯＭＢＡＴＡＮＤＭＡＴＨＥＭＡＴＩＣＩＮＶＥＲＳＥＳＯＬＵＴＩＯＮＣａｏＹｉｈｕａ（ＩｎｓｔｉｔｕｔｅｏｆＦｌｕｉｄＭｅｃｈａｎｉｃｓ，ＢｅｉｊｉｎｇＵｎｉｖｅｒｓｉｔｙｏｆＡｅｒｏｎａｕ...     

浅析飞机的大攻角气动问题及其研究方法

本文分析了现代战斗机的发展趋势,阐明了进行大攻角/过失速机动的必要性,指出解决至今威胁着飞行安全的失速/尾旋问题仍为当代空气动力学家的重任;论述了各种研究大攻角气动问题的方法之优劣;对我国开展大攻角气动问题研究的技术途径提出了一些建议。     

非对称动力机动飞行的载荷研究

通过对一架装有４台涡轮螺旋桨发动机飞机的算例分析,研究了多发动机飞机非对称动力机动飞行的载荷确定方法,指出了影响其飞行载荷的主要因素,给出了非对称动力模拟机动飞行的试飞方法。此外,发现国军标《军用飞机强度和刚度规范》有关条文规定中存在的错误,且提出了相应的修改意见。     

国军标规范飞机气动载荷计算软件研制及其应用

介绍在使用国军标规范《军用飞机强度和刚度规范》中对于急剧俯仰机动、滚转改出及滚转机动机翼载荷计算时所遇到的困难、解决办法及其软件研制。     

NONLINEAR INVERSE SIMULATION FOR THE MANEUVERING FLIGHT OF COAXIAL ROTOR HELICOPTERS

ＮＯＮＬＩＮＥＡＲＩＮＶＥＲＳＥＳＩＭＵＬＡＴＩＯＮＦＯＲＴＨＥＭＡＮＥＵＶＥＲＩＮＧＦＬＩＧＨＴＯＦＣＯＡＸＩＡＬＲＯＴＯＲＨＥＬＩＣＯＰＴＥＲＳＣａｏＹｉｈｕａ（ＩｎｓｔｉｔｕｔｅｏｆＡｉｒｃｒａｆｔＤｅｓｉｇｎ，ＢｅｉｊｉｎｇＵｎｉｖｅｒｓｉｔ...     

Hierarchical global search for fuel-optimal impulsive transfers between lunar libration orbits

The attention to the periodic orbit in the Earth-Moon restricted three-body system continues to grow due to its special environment and locations. This research investigates the feasibility of constructing fuel-optimal single and multiple impulse transfers between unstable periodic orbits at L₁ and L₂ points. Invariant manifolds, which could provide the appropriate initial trajectories for optimization, are analyzed deeply to enable previously unknown orbit options and potentially to reduce mission cost. A global search strategy based on comparing the orbital state of the unstable and stable manifolds, incorporated with low-thrust techniques, is performed to seek a suitable matching point for maneuver application. Then the sequential quadratic programming (SQP) is adopted to further optimize the velocity increment and obtain the single/multiple impulse optimal transfers. The associated constraint gradients are derived to achieve higher accuracy and rapidity of the algorithm. To highlight the effectivity of the transfer scheme, three-dimensional low-energy transfers between different types and spatial regions of performing single and multiple impulses are explored. The total Delta-V required varies between a few meters per second and tens of meters per second, and the related flight time is about several weeks, mainly depending on the energy of periodic orbits and the invariant manifold structure. The results obtained in this paper can provide a useful reference for the selection of escape and capture site along the manifolds, maneuver magnitude and transfer time.     

由稳态飞行确定纵向气动导数

研究了从稳态对称飞行数据估计气动导数的一种方法，要估计的导数是纵向静稳定性和操纵性导数，尾翼产生的阻尼导数、速度对升力和俯仰力矩系数影响的导数，其方法是基于扩展的纵向静稳定性和操纵性理论以及相应的飞行试验数据表示方法，对于大多数气导数，假设飞行测量数据是以平衡曲线和ＣＬ（α）曲线形式给出的，导数估计表达式是由已知常数，直接或非直接测量量的代数关系式构成，估计精度用结果标准误差或系统误差带表示。所研