高超声速飞行器末端导引与控制一体化研究

针对高超声速飞行器末制导阶段参数不确定性和耦合性强的特点,提出了导引与控制协调的一体化设计思路,建立了非线性受扰动的导引与控制一体化控制模型。结合自适应比例导引律特点,通过分段对模型简化,降低了控制律的设计难度。针对气动模型非线性不精确问题,给每段设计了鲁棒自适应BackStepping滑模控制器,再将各段控制律在时间上融合。针对控制回路饱和与延迟特性,提出一种将导引指令缩放和相位提前的修正方法。仿真结果表明,所提方法可行有效,鲁棒性强。     

太阳能无人机能源系统的关键技术与发展趋势

作为探索临近空间领域的新兴飞行器，太阳能无人机（SUAV）在性能、技术及任务航时均呈现出不同于传统飞行器的新特点。其中，太阳能无人机能源系统的比能量、比功率是影响飞机整体性能的核心因素。因此，本文首先对太阳能无人机的太阳电池、储能电池的发展现状进行了阐述，然后针对能量获取多元化、能源系统管理高效化、能源载荷一体化方向对太阳能无人机能源系统的未来发展趋势进行了展望。     

可重复使用运载器再入轨迹与制导控制方法综述

可重复使用运载器（RLV）是未来实现快速、可靠及廉价进出空间的必然趋势，也是当前航空航天领域的研究热点。对RLV再入段的轨迹优化、制导及控制方法进行了综述。在RLV再入轨迹优化方法上，分别从间接法、直接法以及伪谱法等方面进行了综述，在深入分析每类方法特点的基础上，对其未来发展趋势进行了展望；在RLV再入制导方法上，分别从离线标称轨迹制导、在线轨迹重构制导、预测校正制导等方面进行了综述，对每类再入制导方法进行了优缺点分析，并对未来发展方向进行了总结；在RLV再入姿态控制方法上，分别从线性控制方法、非线性控制方法、智能控制方法等方面对其进行了综述，并对其特点和未来发展趋势进行了分析。最后，对RLV再入制导控制一体化方法进行了综述，指出了未来RLV制导控制一体化研究中亟需解决的关键问题。     

带减阻杆高超声速飞行器外形气动特性研究

采用高超声速风洞测力试验方法测量钝头飞行器头部减阻杆的高超声速气动特性,研究减阻杆的气动减阻原理,分析了多组不同构型减阻杆的减阻效果。结果表明,减阻杆显著减少了钝头飞行器高超声速的阻力,最大的减阻率达到60％之多;减阻效果与减阻杆构型和迎角状态密切相关;减阻杆会诱发稳定性、“热斑”以及非定常脉动等不利问题。     

基于光学导引的无人机自动着陆控制系统设计

针对目前无人机采用的某些着陆导引方式存在的覆盖面积小、易受干扰等缺点,设计了基于光学导引系统的无人机自动着陆控制系统.建立了某型无人机的纵向和横侧向的线性方程,结合光学导引系统的性能指标提出了光学导引自动着陆系统的总体结构,设计了理想下滑轨迹和自动着陆控制律方案,将光学导引系统和自动着陆控制系统结合在一起,运用经典PI...     

Stability analysis of explicit guidance laws for space launch vehicles with varying thrust integrals

In this study, a stability analysis of the explicit guidance laws for space launch vehicles is performed with consideration of varying thrust integrals. Among various forms of explicit guidance, linear tangent guidance in its general form is selected and six different acceleration profiles are considered for this numerical experiment. A linear system modeling which includes all of the significant dynamic elements of a space launcher is performed to analyze the effect of the characteristics of thrust integrals on stability margins. Numerical results show that in an aspect of guidance stability, it is advantageous to have thrust integrals derived from increasing acceleration profiles, such as constant thrust case, which may be considered in the development of propulsion systems. Finally, time-domain simulation with the original nonlinear models is performed to verify the approach and the result shows that the nonlinear dynamics of the system is conserved well in the linear model.     

高超声速滑翔飞行器摆动式机动突防弹道设计

 为提高大升阻比高超声速滑翔飞行器机动突防能力,提出了一种侧向摆动式机动弹道的设计方法。基于动态逆的思想,建立了侧向摆动式机动弹道的弹道形式和所需倾侧角间的关系模型;在平衡滑翔假设下,将包括动压、过载和热流在内的飞行约束转化为迎角约束,从而确定了迎角-速度飞行走廊;在此基础上,设计了平衡滑翔情况下满足侧向摆动式机动及飞行约束所需的迎角变化规律。根据所设计的迎角和倾侧角,即可实现平衡滑翔情况下预定机动模式的侧向机动。以HTV(Hypersonic Technology Vehicle)为例进行仿真分析,结果表明该方法能够快速设计出预定机动幅度和机动频率的侧向摆动式机动突防弹道。     

可重复使用助推器调姿转弯段的控制系统设计

针对可重复使用助推器（RBV）强非线性、强耦合、多输入/多输出的特点,在姿态变化剧烈及空域变化广的调姿转弯阶段,采用非线性动态逆控制方法设计RBV的姿态控制系统。根据时标分离原则及奇异摄动理论,将系统分为快慢两回路子系统。对所需的总控制力矩进行控制分配,由空气舵和反作用控制系统（RCS）共同执行。仿真结果表明：由该法可获得较好的动态性能和鲁棒性。     

基于滑模控制的末端能量管理方法

简要介绍了末端能量管理的研究情况,然后对末端能量管理段进行轨迹规划。在轨迹规划的基础上,设计基于滑模变结构控制的制导律,对轨迹进行跟踪,对能量进行管理。仿真结果表明,滑模变结构控制在末端能量管理制导中合理、有效,具有很强的鲁棒性。     

Three-dimensional path planning for unmanned aerial vehicle based on interfered fluid dynamical system

This paper proposes a method for planning the three-dimensional path for low-flying unmanned aerial vehicle(UAV) in complex terrain based on interfered fluid dynamical system(IFDS) and the theory of obstacle avoidance by the flowing stream. With no requirement of solutions to fluid equations under complex boundary conditions, the proposed method is suitable for situations with complex terrain and different shapes of obstacles. Firstly, by transforming the mountains, radar and anti-aircraft fire in complex terrain into cylindrical, conical, spherical, parallelepiped obstacles and their combinations, the 3D low-flying path planning problem is turned into solving streamlines for obstacle avoidance by fluid flow. Secondly, on the basis of a unified mathematical expression of typical obstacle shapes including sphere, cylinder, cone and parallelepiped, the modulation matrix for interfered fluid dynamical system is constructed and 3D streamlines around a single obstacle are obtained. Solutions to streamlines with multiple obstacles are then derived using weighted average of the velocity field. Thirdly, extra control force method and virtual obstacle method are proposed to deal with the stagnation point and the case of obstacles’ overlapping respectively. Finally, taking path length and flight height as sub-goals, genetic algorithm(GA) is used to obtain optimal 3D path under the maneuverability constraints of the UAV. Simulation results show that the environmental modeling is simple and the path is smooth and suitable for UAV. Theoretical proof is also presented to show that the proposed method has no effect on the characteristics of fluid avoiding obstacles.