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时间协同攻击是提高弹道导弹突防能力和作战效能的一种重要手段。由于发动机推力偏差等干扰因素造成导弹的飞行时间偏差较大,为精确控制弹道导弹的飞行时间,运用BP神经网络算法,建立了一种适用于较大飞行时间偏差修正的飞行时间调控模型。该模型用视加速度偏差表征推力偏差等干扰的影响,根据视加速度偏差调整导弹飞行中某一时段的程序角来实现对飞行时间的精确控制。由BP神经网络建立满足飞行时间偏差要求下视加速度与飞行程序角速率、转弯结束时间之间的映射关系。导弹实际飞行时,根据实际视加速度,由BP神经网络在线计算出飞行程序角速率及转弯结束时间,使导弹在干扰条件下仍以预定飞行时间到达目标。最后,通过仿真验证了该模型的有效性和可行性。 相似文献
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The automatic flight control computer was a revolutionary development in the early days of flight, even in its primitive electromechanical form. It evolved into an electronic computing device, starting as an analog computer and maturing into software run on a digital, general-purpose microprocessor. The current accepted industry standard is to use a dedicated microprocessor in its own enclosure for this function that is essentially firewalled from the rest of the systems on the aircraft. This paper will explore the opportunity to integrate the flight control function into an integrated processing platform, which is a robustly partitioned platform that supports multiple functions of dissimilar design assurance levels. This approach provides all of the benefits of an integrated system, while still maintaining the separation provided by a stand-alone unit. The paper will consider both the advantages and disadvantages of this approach. The discussion will describe each of the alternatives in general and then focus specifically on autopilot and flight control functions that have potential for integration. The end goal of the paper is to impress on the reader an understanding of the different alternatives available for autopilot, flight control, and avionics modernization in general. This includes the development of a selection matrix that will assist the reader in making decisions on how best to implement these functions according to criticality and the volatility of their future requirements 相似文献
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发展了一种集成旋翼状态反馈(Rotor-State Feedback,RSF)控制的飞行控制系统,以提升直升机在大气紊流环境中低速飞行时的飞行品质。基于经典显模型跟踪控制系统,对机体和旋翼状态反馈增益进行协同设计,以综合优化旋翼/机体耦合动稳定性和直升机在飞行品质相关频率范围(1~12rad/s)内的紊流缓和能力。同时,设计了一个旋翼前馈控制以增强直升机的操纵响应特性。对直升机飞行品质的线性分析表明:RSF控制的引入能够在实现旋翼/机体耦合动稳定性控制的同时使滚转和俯仰通道的指令跟踪延迟时间分别降低21.87%和25.82%,扰动抑制带宽分别提升243.22%和72.56%。最后以飞行试验验证的高阶非线性飞行动力学模型进行数值模拟验证控制系统。结果表明:RSF控制的引入使直升机滚转、俯仰角速率对紊流响应的标准差分别降低55.68%和26.81%。集成RSF的控制系统能够提升直升机在紊流中的飞行品质。 相似文献
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提出了常规试飞应把握的三个环节(做好试飞准备、掌握试飞方法、严格试飞标准)和常规试飞的主要项目(测试和调整旋翼与尾桨震动度、检查和调整旋翼自转转速、检查和调整操纵系统间隙与摩擦力、检查和校验发动机功率)及方法,为直升机试飞员和有关工程技术人员提供参考。 相似文献
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《中国航空学报》2023,36(4):409-422
The flight-structural dynamics of a high-aspect-ratio wing challenge the flight control design. This paper develops a reduced model of coupled dynamics with stability consideration. The structural dynamics are formulated with dihedrals, and the central loads drive the deformation. The control-oriented model with essential coupled dynamics is formulated. Modal sensitivity analysis and input–output pairing are performed to identify the control structure. Besides, an example of flight control design is provided to discuss the necessity of considering structural dynamics in controller design. Analytical coupled flight dynamics provide a system-theoretic approach for stability and facilitate model-based control techniques. Simulation results reveal the characteristics of flight-structural coupled dynamics and demonstrate that the influence of flexible modes should be considered in control design, especially in lateral dynamics. 相似文献
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《中国航空学报》2016,(3):596-607
To analyze the parachute dynamics and stability characteristics of precision airdrop system,the fluid–structure interaction(FSI) dynamics coupling with the flight trajectory of a parachute–payload system is comprehensively predicted by numerical methods.The inflation behavior of a disk-gap-band parachute is specifically investigated using the arbitrary Lagrangian–Euler(ALE) penalty coupling method.With the available aerodynamic data obtained from the FSI simulation,a nine-degree-of-freedom(9DOF) dynamic model of a parachute–payload system is built and solved to simulate the descent trajectory of the multi-body dynamic system.Finally,a linear five-degree-of-freedom(5DOF) dynamic model is developed,the perturbation characteristics and the motion laws of the parachute and payload under a wind gust are analyzed by the linearization method and verified by a comparison with flight test data.The results of airdrop test demonstrate that our method can be further applied to the guidance and control of precision airdrop systems. 相似文献
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Reconfigurable Flight Control Design for Combat Flying Wing with Multiple Control Surfaces 总被引:2,自引:2,他引:0
With control using redundant multiple control surface arrangement and large-deflection drag rudders,a combat flying wing has a higher probability for control surface failures.Therefore,its flight control system must be able to reconfigure after such failures.Considering three types of typical control surface failures(lock-in-place(LIP),loss-of-effectiveness(LOE) and float),flight control reconfiguration characteristic and capability of such aircraft types are analyzed.Because of the control surface redundancy,the aircraft using the dynamic inversion flight control law already has a control allocation block.In this paper,its flight control configuration during the above failures is achieved by modifying this block.It is shown that such a reconfigurable flight control design is valid,through numerical simulations of flight attitude control task.Results indicate that,in the circumstances of control surface failures with limited degree and the degradation of the flying quality level,a combat flying wing adopting this flight control reconfiguration approach based on control allocation could guarantee its flight safety and perform some flight combat missions. 相似文献
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《中国航空学报》2023,36(3):357-367
Flight delay prediction has attracted great interest in civil aviation community due to its significant role in airline planning, flight scheduling, airport operation, and passenger service. Flight delay is affected by numerous factors and irregularly propagates in air transportation networks owing to flight connectivity, which brings critical challenges to accurate flight delay prediction. In recent years, Graph Convolutional Networks (GCNs) have become popular in flight delay prediction due to the advantage in extracting complicated relationships. However, most of the existing GCN-based methods have failed to effectively capture the spatial–temporal information in flight delay prediction. In this paper, a Geographical and Operational Graph Convolutional Network (GOGCN) is proposed for multi-airport flight delay prediction. The GOGCN is a GCN-based spatial–temporal model that improves node feature representation ability with geographical and operational spatial–temporal interactions in a graph. Specifically, an operational aggregator is designed to extract global operational information based on the graph structure, while a geographical aggregator is developed to capture the similar nature among spatially close airports. Extensive experiments on a real-world dataset demonstrate that the proposed approach outperforms the state-of-the-art methods with a satisfying accuracy improvement. 相似文献
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H_∞控制理论在飞行力学中的应用 总被引:1,自引:0,他引:1
对 H∞ 控制理论在飞行力学中的应用进行了研究。以典型战斗机的横航向飞行机动为例,介绍了将飞行控制系统设计问题转化为标准的 H∞ 控制问题,继而进行 H∞ 控制器设计,以提高其机动特性的鲁棒性。采用显模型跟踪技术,飞行品质的要求包含在反映状态变量侧滑角、稳定轴角速率对指令输入响应的理想模型中,通过使理想模型输出和实际对象输出之间的加权误差最小,同时保证控制面不饱和来达到控制的目的。计算结果表明,在飞机模型气动参数存在不确定性的情况下,增广系统达到了期望的性能指标,显示出良好的鲁棒性。 相似文献
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《中国航空学报》2021,34(1):50-67
This paper proposes a novel hybrid algorithm called Fractional-order Particle Swarm optimization Gravitational Search Algorithm (FPSOGSA) and applies it to the trajectory planning of the hypersonic lifting reentry flight vehicles. The proposed method is used to calculate the control profiles to achieve the two objectives, namely a smoother trajectory and enforcement of the path constraints with terminal accuracy. The smoothness of the trajectory is achieved by scheduling the bank angle with the aid of a modified scheme known as a Quasi-Equilibrium Glide (QEG) scheme. The aerodynamic load factor and the dynamic pressure path constraints are enforced by further planning of the bank angle with the help of a constraint enforcement scheme. The maximum heating rate path constraint is enforced through the angle of attack parameterization. The Common Aero Vehicle (CAV) flight vehicle is used for the simulation purpose to test and compare the proposed method with that of the standard Particle Swarm Optimization (PSO) method and the standard Gravitational Search Algorithm (GSA). The simulation results confirm the efficiency of the proposed FPSOGSA method over the standard PSO and the GSA methods by showing its better convergence and computation efficiency. 相似文献
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《中国航空学报》2022,35(10):95-105
The Stopped-Rotor (SR) UAV combines the advantages of vertical take-off and landing of helicopter and high-speed cruise of fixed-wing aircraft. At the same time, it also has a unique aerodynamic layout, which leads to great differences in the control and aerodynamic characteristics of various flight modes, and brings great challenges to the flight dynamics modelling and control in full-mode flight. In this paper, the flight dynamics modelling and control method of SR UAV in full-mode flight is studied. First, based on the typical flight profile of SR UAV when performing missions, using the theory and method of fuzzy mathematics, the T-S flight dynamics model of SR UAV in full-mode flight is established by synthesizing the flight dynamics model of each flight mode. Then, an explicit model tracking and parameter adjusting control system based on fuzzy theory is designed to enhance the stability of the inner loop of SR UAV in full-mode flight, which effectively reduces the coupling between axes and improves the control quality of the system. Finally, the outer loop control system is designed by using classical control method, and the control law of SR UAV in full-mode automatic flight is obtained. The simulation results show that the proposed control system design method is feasible and effective, which lays a solid foundation for the subsequent engineering implementation of the SR UAV. 相似文献
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The drive for greater cost-effectiveness and improved safety/security in an environment of increasing air movements calls for improved availability of accurate and consistent flight data to stakeholder systems. Studies conducted by EUROCONTROL in 2001-2003 indicate significant levels of inconsistency between flight data available to aircraft operators, air traffic control (ATC), air traffic flow management (ATFM), airports and military systems, causing unnecessary workload, inefficient use of resources, and unnecessary delays. Eurocontrol's new flight data interoperability concept is intended to resolve this problem. Having passed through the initial feasibility phase, this concept is now entering the development phase, in which it will become the basis for the development of a draft interoperability standard to be used in Europe for the specifications of new flight data processing systems deployed from 2007 onwards, and potentially to be proposed to the International Civil Aviation Organisation (ICAO) for global standardisation. 相似文献
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具有过失速机动能力的战斗机在近距空战中能够取得快速占位、先敌瞄准、有效规避攻击的战术优势,是先进战斗机的标志性性能要求。模型飞行试验技术作为空气动力学研究三大手段之一,在解决飞行器技术难题、实现技术创新方面发挥了重要作用。本文介绍了中国空气动力研究与发展中心利用带动力自主控制模型飞行试验平台发展的过失速机动模型飞行试验技术,以及开展的先进战斗机构型典型过失速机动模型飞行试验,分述了在大迎角非定常气动建模、宽量程气流系参数测量、大迎角非线性控制、推力矢量控制、大迎角非定常气动参数辨识方面的研究工作与解决这些关键问题的技术途径。通过此项研究,在国内首次实现了先进战斗机构型缩比模型典型过失速机动飞行,相关研究成果可为先进战斗机实现过失速机动飞行能力提供有力的技术支撑。 相似文献
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近20年来,变结构系统(VSS)理论的发展日益引人注目。本文旨在将变结理论引入到飞行控制系统的设计,并提出一种新的设计方法和工程实现的方案,通过系统仿真,证实了这种方法和方案是可行的。 在变结构飞行控制系统的设计上,Anthong J.Calise和Friedrich S.Kramer以及C.M.Derling先后研究了在一定飞行状态下变结构系统对相对飞行模型误差的鲁棒性的影响。本文将讨论飞行状态(空域,速度等)变化情况下,VSS的控制效果,并以某型无人机为例,与传统的PD控制结果进行比较。研究将集中于飞机的纵向运动控制。 相似文献
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讨论了涡轮螺桨飞机阻力极曲线值得注意的一些特点,并介绍了根据这些特点而提出的试飞确定涡桨飞机飞行性能和升阻特性的一种“等质量法”该方法先把各种飞行条件下获得的试飞数据算到的标准条件,然后利用参数组合的线性关系来简化数据处理,具有简单易行的优点。 相似文献