飞机超低空投弹安全性研究

建立了某型飞机超低空投弹的数学模型,分别研究了本体飞机投弹后的动态响应、自动驾驶仪打开时飞机投弹后的动态响应以及在风扰动下投弹后的动态响应。研究结果表明,飞机超低空单侧投弹在自动驾驶仪打开时飞机纵向和横航向动态响应较小,可以满足投弹的要求;超低空飞行风扰动对飞机动态响应有一定的影响,但飞机仍具有投弹的能力。给出了超低空投弹的安全操纵策略,对工程应用有一定的参考价值。     

非对称投弹及非对称挂载补偿控制技术研究

针对战斗类飞机非对称投弹和非对称挂载这类情况,分析了投弹时横向扰动及纵向机动时横向耦合的机理,描述了其对飞行安全的威胁;通过引入所投弹质量、位置以及飞机法向过载,设计了非对称投弹/非对称挂载补偿控制律.仿真验证结果表明:该补偿控制律可消除上述两种情况下的横向扰动,有助于非对称投弹时飞机状态的保持,更重要的是提高了非对称挂载情况下着陆的安全性.     

内埋武器投放分离相容性的风洞投放试验预测与评估

采用基于运动动力学相似的风洞投放试验对先进战斗机内埋武器投放分离相容性进行预测与评估，给出载机在不同飞行马赫数、攻角、弹舱长深比及舱内武器剩余数量、不同弹射力、折叠翼是否展开下，内埋导弹从载机弹舱投放分离后的运动轨迹和俯仰姿态角变化规律，研究这些因素对内埋导弹投放分离相容性的影响。结果表明：处于超声速飞行状态下（马赫数为1.5）的载机，攻角处于0°、2°、3°时投放内埋导弹后弹体俯仰角处于低头状态，利于攻击载机前下方敌方目标；在给定的初始分离条件下，对于两种不同的弹舱长深比，内埋导弹均能安全分离，但对内埋导弹俯仰方向运动影响较为显著；弹舱内武器剩余数量对内埋导弹分离特性影响较小，导弹能快速地远离载机干扰流场，投放分离后弹体俯仰角一直处于低头状态；随着内埋导弹初始分离速度增大，可使弹体快速地穿过载机的下洗流场，有利于内埋导弹与载机的安全分离；导弹的不同气动布局对内埋导弹分离相容性有一定的影响。     

基于建模仿真的飞机桶滚机动规避空空导弹效果及原因分析

基于飞机桶滚机动规避空空导弹攻击的作战背景,建立了导弹与飞机的空间交会模型。以导弹脱靶量、过载以及舵偏角速率为依据,对桶滚机动不同机动时机、周期下的规避效果以及规避原因进行了仿真分析。研究结果表明,导弹脱靶量与机动时机的关联性较弱,可随着机动周期的增大而减小。当机动周期为 2~3 s时,导弹脱靶量较大,飞机规避效果较好。飞机桶滚机动规避导弹的原因不仅在于导弹交会过程中过载的增大,而且还在于导弹交会过程中舵偏角速率的增大。     

外挂物投放问题的二维非结构动态网格技术研究

以动态网格守恒型方程为控制方程,在二维非结构网格基础上发展了弹簧式光顺法和局部网格重构法两种动态网格变形技术。结合运动轨迹计算方程,将动态网格法应用于飞机外挂物投放问题中,成功模拟了导弹自由投放的整个过程,获得了详细的包括弹体运动速度、运动轨迹和受力情况等在内的丰富的流场信息。成功的应用不仅验证了动态网格法的可行性;而且也表明,动态网格法的进一步完善与发展将成为解决外挂物投放问题的有力工具。     

作战飞机悬挂发射技术面面谈

悬挂发射系统是飞机与机载武器之间的连接部分,它与机载火控系统配合,承担肴导弹、航空炸弹等悬挂物的运载及投射功能。飞机挂载炸弹、水雷、鱼雷等武器的配套装置称作悬挂投放装置;     

导弹攻击机机载雷达的选择

机载雷达是导弹攻击机火力控制系统的重要组成部分。它可使飞机在昼夜和复杂气象条件下具有独立作战的能力。导弹是一种远航程的武器,飞机借助雷达能远距离发现、跟踪目标之特性,及早发现、识别目标,占据有利战术位置,发射导弹,对目标进行攻击。 本文根据发射导弹的技术要求,对雷达的主要战术技术指标,雷达在飞机攻击过程中的战术使用,国内雷达的技术性能比较、选型等方面进行讨论。     

某型导弹的地面模拟方法研究

为了更好地在地面保障时验证飞机挂弹系统逻辑的正确性,设计了一种便携式导弹模拟系统。该系统在传统导弹模拟系统的基础上采用FPGA作为主控单元,通过制定通信协议控制离散IO模块采集飞机至导弹的控制指令以及继电器模块模拟导弹至飞机的响应信号,实现模拟真实导弹准备过程、发射前后控制指令等信号处理流程。该系统通过了在机上进行的实际验证,效果较好,能够满足地面保障使用。     

低空多目标点连续精确快速空投路径规划

正当自然灾害、事故发生时,救援任务就变得十分迫切,其中救援物资的投放是救援任务中不可或缺的一部分。然而,在很多情况下,车辆、船舶等救援运输工具不能快速甚至不能到达事故现场,因此,采用空投方式投放救援物资就变得非常关键。采用空投方式进行救援物资的投放,必然要对飞机在飞行过程中的投放点进行规划,之前有专家、学者对此做过分析研究,对飞机的飞行轨迹进行了规划[1],如图1     

低价位的全天候精确制导武器

在现代战争中，精确制导武器的作用越来越突出，因为它充分体现了“伤其十指不如断其一指”，集中力量进行攻击的作战原则。所谓精确制导武器一般是指带有制导装置的炸弹、滑翔炸弹和空面导弹。美国在越南战争时所投的精导武器只占投弹总量的约０．２％，在海湾战争所占的比例也不到１０％。而在最近的科索沃冲突中，美国空投的大部份武器都是精确制导武器。采用精导武器还可提高载机的生存力。随着地面空防系统的改进，以及攻击飞机数量的减少，精导武器在对地攻击中将越来越重要。采用精导武器的前提是要有很强的情报和侦察能力，需用卫星…     

Evaluation on novel architecture for harmonizing manual and automatic flight controls under atmospheric turbulence

Pilot uncertainty in aircraft response under automatic flight control has triggered aircraft accidents/incidents in the past. This uncertainty compels a pilot to disengage autopilot and switch to manual control. However, the decision to disengage autopilot and when to do it can be difficult: especially if there is not enough time to monitor the cockpit displays, for instance while countering atmospheric turbulence. Against this background, we proposed the “human as a control module” architecture for harmonizing pilot and autopilot controls. The architecture blends pilot maneuver with autopilot control instead of switching between them when simultaneous inputs are given to the aircraft. By automatically adjusting pilot and autopilot control inputs, the architecture avoids overlaps of both control authorities and helps to circumvent the effect of conflicting actions. This paper applies the architecture to the situations of past aircraft incidents which had been caused by the transfer from autopilot control to pilot maneuver after encountering atmospheric turbulence. The effectiveness of the architecture is evaluated via simulation study for the specific incident examples. Furthermore, this paper extends the architecture with an Extended Kalman Filter (EKF) based observer and evaluates its robustness under errors in wind estimation.     

某型飞机角位移自动驾驶仪比例式控制规律设计与仿真

现代飞机越来越复杂的飞行任务对飞机控制系统性能提出了更高要求,而飞机控制系统性能的好坏与飞机自动驾驶仪控制规律设计的优劣关系密切.为此,对某型飞机自动驾驶仪的比例式控制规律进行了分析和设计,仿真研究了控制规律中的速率反馈及位置反馈的作用和选取原则,进而设计出性能良好的飞机角位移自动驾驶仪比例式控制规律.通过大量仿真比较...     

基于空中发射点的在线诸元计算方法研究

现代战争的快节奏要求弹道导弹具有快速机动发射能力,采用伪卫星组合制导的弹道导弹随机快速发射需要诸元在线计算。提出了一种基于空中发射点的在线诸元计算方法,该方法具有计算量小、制导方法误差小的特点,可用于陆基机动弹道导弹或潜射弹道导弹的快速发射。     

基于NBF网络的导弹航向平面滑模控制导引一体化

提出了一种反舰导弹针对水面机动目标的航向平面控制导引一体化设计方案。建立了航向平面的一体化控制导引模型,然后基于NBF网络切换增益调节和滑模控制的思想进行了控制导引律的设计,为了验证该一体化设计的有效性和正确性,进行了仿真计算。仿真结果表明,针对高机动的水面目标命中精度很高。     

To estimation of control law parameters for the lateral motion of aircraft taking into account wind disturbances

We consider the problem of adjusting the gear ratios of the aircraft autopilot without data on bank taking into account wind disturbances caused by atmospheric turbulence. The theory of Markov processes and extremal challenges is used to solve the problem. We present an example of adjusting autopilot gear ratios for the aircraft—autopilot dynamics system under wind disturbances.     

Missile autopilot design via functional inversion and time-scaled transformation

This paper presents a new approach to acceleration control of STT (Skid-To-Turn) missiles. In the design and stability analysis of our autopilot, we assume perfect roll-stabilization but consider fully all other nonlinearities of the missile dynamics including the coupling effect due to bank angle. Our autopilot controller consists of a partial-linearizing controller and a dynamic compensator. The partial-linearizing controller along with a time scaled transformation can convert the nonlinear missile dynamics to the so-called normalized system which is completely independent of Mach number and almost independent of air density. The dynamic compensator is designed based on this normalized system. This normalized system greatly simplifies the design process of an autopilot controller regardless of flight conditions. Our autopilot controller can provide fast and exact set-point tracking performance but without the slow-varying conditions on angle of attack and side-slip angle required often in the prior works.     

New criterion for aircraft susceptibility to infrared guided missiles

This paper assesses aircraft susceptibility from the first principles, with respect to the threat posed by passively guided infrared homing missiles; with an objective of gaining insight into the comprehensiveness of the relationship between aircraft susceptibility and aircraft infrared signature level. The conventional criterion of aircraft susceptibility assessment based on its lock-on envelop is found to be inadequate, and a new criterion termed here as the Lethal Envelop is presented. The proposed susceptibility assessment criterion is more relevant for coming generation of infrared-guided missiles, because of advancements in the infrared detection technology. A threshold infrared signature level is also proposed as benchmark to be satisfied by all infrared signature suppression systems; if aircraft susceptibility to infrared guided missiles is to be reduced. This analysis is vital for gauging the effectiveness of infrared signature suppression systems. A typical air-to-air combat situation is simulated, and the results that lead to aircraft susceptibility assessment are obtained from this model, which illustrates the comprehensiveness of the redefined aircraft susceptibility assessment approach.     

Nonlinear autopilot for high maneuverability of bank-to-turnmissiles

This paper presents a novel approach to autopilot design for highly maneuvering bank-to-turn (BTT) missiles. In the design and performance analysis of the proposed nonlinear autopilot, all nonlinearities of missile dynamics including the coupling between roll, yaw, and pitch channels as well as the asymmetric structure of missile body are taken into full account. It is shown that through a kind of feedback linearization technique along with a singular perturbation-like technique, the input/output (I/O) dynamic characteristics of pitch, yaw, and roll channels are made linear, decoupled, and independent of flight conditions such as air density and missile velocity. In particular, the proposed autopilot controllers can provide excellent set-point tracking performance for roll and pitch channels while keeping the side-slip angle negligible. The generality and practicality of our approach are demonstrated through mathematical analysis and various simulation results using an ILAAT missile     

“长空”超低空无人驾驶飞机的飞行控制系统

 本文介绍“长空”超低空无人驾驶飞机的飞行控制系统。这是我国首次将单片计算机应用到无人机的飞控系统。文中对方案选择,控制规律以及为满足超低空飞行高度精度的要求所采取的技术措施作了详细的阐述,通过试飞,鉴定、供靶,说明这一套数模混合式飞控系统的设计是完全成功的。