捷联制导旋转弹制导信息提取研究CSCD

以捷联式半主动激光导引头为研究对象,研究其应用在旋转弹上制导信息的提取方法。根据坐标转换关系得到旋转弹惯性系视线角解耦模型,由于导引头和速率陀螺仪具有测量误差特性,直接解耦得到的制导信息会产生较大的误差。基于视线角解耦模型的非线性,采用扩展卡尔曼滤波(EKF)的方法对测量信息进行滤波处理,估计出目标的位置,从而得到捷联式半主动激光导引旋转弹的制导信息。将扩展卡尔曼滤波方法与α-β滤波方法进行对比分析,得到扩展卡尔曼滤波方法对捷联式半主动激光导引旋转弹制导信息的估计精度更高,收敛更快。     

基于视线角序列的机动目标视线角速率计算

 依据拦截弹与机动目标间的相对位置关系,采用导引头球面模型,基于当前统计模型,实现了强跟踪状态自适应滤波,计算出了可用于制导的视线角速率。该算法利用导引头球面模型,将测角信息转换成距离信息,进行方差自适应调整和卡尔曼滤波。在只给出视线角序列信息的情况下,根据相对状态滤波结果求出所需的视线角速率。     

Relative targeting architectures for captive-carry HIL missilesimulator experiments

Captive-carry electronic warfare (EW) tests evaluate the response of hardware-in-the-loop (HIL) missile seekers to an actual environment (test-range) including the presence of electronic attack. This paper describes a relative targeting architecture that displays the test-range results in geodetic coordinates using only the sensors available on board the captive-carry platform (GPS, INS, seekers). To derive the target position in geodetic coordinates, a lever-arm correction process is described that determines the position of each seeker and the corresponding pitch and yaw of the simulator. Combining the positional parameters of the seeker with its targeting variables, the seeker track point is displayed in geodetic coordinates, A track tagging algorithm is presented to identify the true target from the EW disruption using the drift angle from the inertial navigation system (INS), To eliminate the scintillation noise present in the track image, a Kalman filter in sensor coordinates is applied to the targeting variables allowing optimization of the track tagging. Experimental results from a recent EW field test using antiship cruise missile simulators are shown to demonstrate the feasibility of the approach for determining EW effectiveness in near real-time. Targeting accuracy is also quantified by comparing the derived target position with the true Global Positioning System (GPS) test-range position of the ship in the absence of electronic attack     

基于对数极坐标变换的快速相关匹配算法

成像制导过程中,需要在导引头获得的图像中搜索目标所在位置。基于对数极坐标变换的相关匹配算法能够有效处理在尺度、旋转等情况下目标的匹配问题,但是计算量大、匹配效率低,因此提出一种基于对数极坐标变换的多分辨率快速相关匹配算法。首先,通过定义主梯度方向,并将该方向作为对数极坐标变换的角度变换基准,有效避免了模板与目标特征矩阵基准不同的问题;其次,在多分辨率金字塔搜索过程中,采用图像方差作为判断依据,跳过同质区域和杂乱区域等非目标区域,加快搜索效率。仿真结果表明,该算法相比传统多分辨率相关匹配算法能够保证匹配精度并提高算法对于非线性光照变化的鲁棒性,匹配效率显著提高,具有实时处理的潜力。     

基于结构不确定性的非线性鲁棒制导律设计

根据多普勒雷达导引头和红外成像导引头多模制导导弹弹道中段制导信息精度的特点,以非线性鲁棒控制理论为依据,设计了一种制导律.仿真结果表明,该制导律对弹目相对距离测量干扰有较好的鲁棒性,对目标大机动也有鲁棒性.因此,这种制导律可以作为多普勒雷达导引头和红外成像导引头多模制导导弹弹道中段的制导律使用.     

考虑捷联导引头最小视场角约束的制导策略

针对高超声速飞行器捷联导引头,提出导引头最小视场角（FOV）约束问题。首先分析了导引头视线角变化规律,指出在攻击固定目标时,导引头最小视场角约束在弹道末段无法被满足,导引头将丢失目标。在此基础上,基于缩短导引头丢失目标距离的目标,提出一种满足导引头最小视场角约束的制导策略。该策略不依赖于末制导律形式,当最小视场角约束无法被满足时,改变原有制导指令,主动改变弹道轨迹以增加弹体视线角,避免超出视场范围。其次,针对飞行器过载约束,设计了制导策略切换点,在到达切换点时该制导策略将结束工作,避免末端过载过大超出约束。通过对比仿真验证了所提出制导策略有效性,能够大幅度减少导引头丢失目标距离,工程上有利于提高末端命中精度。     

Coning motion instability of spinning missiles induced by the delay of strap-down seeker

The strap-down seeker, which combines the seeker’s and the onboard gyro’s measurements to obtain the target information, has been extensively applied by spinning missiles. The response delay of the strap-down seeker, a novel factor that could result in crosscoupling between the acceleration commands in the pitch and yaw channels and subsequently cause the significant deterioration in dynamic stability of the spinning missile equipped with a rate loop, is noted in this paper. The sufficient and necessary stability conditions are also analytically established based on the system equation with complex coefficient, which are further verified by numerical simulations. It could be indicated that the response delay of the strap-down seeker will greatly deteriorate the dynamic stability of the whole guidance system designed by the conventional method. It is also noticed from analysis that the stable region of the combined guidance coefficient is shrunken significantly with the increase of the spinning rate.     

一种用于干扰效果评估的闭环制导模拟方法

针对干扰效果评估需求,提出了一种简便易行的闭环制导模拟方法,即将导引头装在飞艇上,利用导引头测量输出的目标信息,按照导引律的要求,实时引导和控制飞艇向目标方向做制导飞行,以模拟闭环制导控制过程.利用电视导引头搭载飞艇,设定直接瞄准法导引律,完成了多个航次的闭环制导飞行试验.结果表明：飞艇飞行航迹与直接瞄准法导引律要求的理论航线基本一致,飞艇纵轴与目标视线的夹角以及导引头测量输出的离轴角均小于1°,也满足直接瞄准法导引律的要求,从而初步验证了所提出闭环制导模拟方法的可行性.这种作制导飞行的飞艇和导引头,可形象直观地演示、验证干扰效果.     

Optimal guidance of extended trajectory shaping

To control missile＇s miss distance as well as terminal impact angle, by involving the timeto-go-nth power in the cost function, an extended optimal guidance law against a constant maneuvering target or a stationary target is proposed using the linear quadratic optimal control theory.An extended trajectory shaping guidance（ETSG） law is then proposed under the assumption that the missile-target relative velocity is constant and the line of sight angle is small. For a lag-free ETSG system, closed-form solutions for the missile＇s acceleration command are derived by the method of Schwartz inequality and linear simulations are performed to verify the closed-form results. Normalized adjoint systems for miss distance and terminal impact angle error are presented independently for stationary targets and constant maneuvering targets, respectively. Detailed discussions about the terminal misses and impact angle errors induced by terminal impact angle constraint, initial heading error, seeker zero position errors and target maneuvering, are performed.     

无导引头也无惯导导弹的协同制导

为了在不依赖导弹间实时通信与导弹绝对位置信息的情况下实现无导引头也无惯导导弹的"发射后不管",考虑为无导引头也无惯导导弹安装两个捷联探测器,从而可对有导引头导弹上的两个特定目标点进行探测。在此基础上,针对静止点目标分别采用一般的负反馈控制方法以及有限时间收敛原理设计了2种协同末制导律,并针对静止面目标采用动态逆控制设计了1种协同末制导律。上述协同制导律均可在有导引头导弹命中目标前实现无导引头也无惯导导弹的速度方向指向其攻击目标,而此后无导引头也无惯导导弹只需要作直线运动即可命中其攻击目标。仿真结果验证了上述协同制导律的有效性以及优势。     

基于视觉引导的无人直升机着舰技术研究

以无人直升机为被控对象,根据实际着舰流程研究了视觉引导系统的软硬件架构。在硬件上通过在摄像头加装云台,避免了无人机因姿态改变造成视野中目标图像的丢失,提高了位姿解算的精度。提出一种以红外灯设计的合作目标图案为着舰目标的视觉引导着舰系统,能够在不同光线强度、复杂周边环境下成功识别合作目标,具有良好的抗噪能力。研究设计了一套图像处理与位姿解算的引导系统,通过实验验证姿态参数的误差在2°以内,位置参数的误差小于2cm,能够满足着舰的精度要求;每帧图像的处理速度在30ms左右,具有良好的实时性。     

射手模型优化与辨识及其对图像制导的影响

基于数据链通信的人在回路制导模式额外引入了射手动力学而且存在图像信号延时,含有射手动力学的控制回路会对目标在视场（LOS）中的误差角进行跟踪补偿,从而提升图像制导弹药的制导控制性能。为探究射手动力学和图像信号延时对人在回路制导性能的影响,基于真实的图像导引头模型及参数,设计校正网络以满足导引头稳定回路的性能需求;引入两类射手模型,针对射手模型2,优化模型结构并通过贴近真实环境的辨识实验得到动力学参数,弥补了现有建模的不足。基于射手对不同图像信号延时的适应性,对比研究了两类射手模型与不同图像信号延时对导引头控制系统稳定性、快速性和人在回路比例导引制导精度的影响。仿真结果表明：图像信号延时越长,导引头跟踪速度越低、误差角越大,制导系统的收敛时间越长;优化后的射手模型2及其参数辨识更准确地描述了射手的操作行为,对制导系统的影响较低且满足系统性能要求。     

导弹红外导引头火箭橇试验评估方法

从武器发展的趋势和红外导引头对外场试验的需求出发,提出了一种能真实模拟红外导引头与目标交会条件的试验方案,介绍了试验系统组成和试验原理,概述了系统的静态标定及联调、开环和闭环试验、抗干扰试验方法。该试验方案可实现红外导引头对高速运动目标的识别,检验其与模拟制导系统结合后对目标的捕获、锁定与跟踪性能。同时,也可有效考核其抗干扰能力,对提高红外导引头和导弹制导控制系统试验技术水平和能力具有重要的技术支撑作用。     

Optical guidance for autonomous landing of spacecraft

An autonomous rendezvous guidance scheme for spacecraft to descend to small celestial bodies by using optical information is presented. First, a new guidance, navigation, and control (GNC) method based on fixation-point (FP) inheritance is proposed. A spacecraft can safely descend toward the target point on the celestial body by tracking and autonomously renewing the FPs on the surface. Next, we deal with the method of extracting the FPs. A spatial band-pass filter (BPF) is applied to pictures taken to enhance features having comparable size with the tracking window. Local variance of the filtered image is used as a criterion of the extraction. Then, the relative information between the spacecraft and the celestial body (position, velocity, attitude, etc.) is calculated from the image coordinates and the range measurements of the FPs from the spacecraft. To suppress observation noise and improve navigation accuracy, an application of the extended Kalman filter is also presented. Finally, simulations are conducted to verify the guidance precision and the fuel consumption of the proposed guidance scheme     

捷联激光制导的视线信号提取方法

提出了一种弹目视线角信号的提取方法,该方法采用UKF解耦,针对捷联激光制导炸弹需要攻击移动目标却不能测量弹目相对距离和速度的情况,建立了弹目相对运动模型,解耦过程不需要相对距离信息,能够更方便地应用于工程实践.经仿真验证,此方法可以较好地估计出弹目视线角以及角速率信息,能够满足捷联激光制导炸弹工程应用的需要.     

激光半主动航空制导武器半实物仿真研究

介绍了激光半主动航空制导武器制导控制系统的系统组成、半实物仿真试验方法、关键参试设备、仿真工作流程及半实物仿真误差干扰因素,通过某型激光半主动制导武器半实物仿真试验验证,结果表明该仿真方法具有很高的可操作性和科学性,能全面地对制导控制系统进行考核,节约了试验成本和仿真时间,对制导控制系统整体性能评估和加快研制进度有重要的意义。     

FDEKF在反辐射无人机抗目标雷达关机中的应用

基于捷联惯导/反辐射导引头组合抗目标雷达关机制导方案,研究了有限差分卡尔曼滤波(FDEKF)方法在对目标雷达被动定位中的应用。考虑反辐射导引头测角存在非线性特性,提出了一种基于扩展状态变量维数的方法实现了目标状态估计和导引头非线性特性补偿。仿真结果表明,FDEKF是一种具有良好性能的非线性滤波方法,可以代替传统的EKF解决反辐射无人机对目标雷达的被动定位问题。     

基于改进RPG方法的MUAVs协同目标跟踪

多无人机(MUAVs)协同Standoff目标跟踪制导律由保持距离的横侧向制导律和保持相对相位角的纵向制导律组成。无人机(UAV)进行Standoff目标跟踪的横侧向制导律采用参考点制导(RPG)方法。针对UAV在基于RPG方法的制导律下存在参考视线与相对速度方向夹角需要保持为锐角、转弯速率在UAV运动方向远离目标情况下太小的不足,提出了改进RPG方法。设计了基于改进RPG方法的MUAVs协同Standoff目标跟踪横侧向制导律和纵向制导律,分析了制导律的稳定性和收敛性,并验证了改进方法的可行性。采用原始RPG方法和改进RPG方法对UAV分别跟踪静止目标和跟踪运动目标进行仿真的结果表明,UAV处于任意初始位置及飞行方向都能快速进入到期望飞行轨迹,应用改进RPG方法可使UAV围绕目标顺时针飞行或者逆时针飞行,验证了改进RPG方法比原始RPG方法的效率更高。     

三维空间拦截的前置追踪变结构制导律(英文)

This article aims to develop a head pursuit （HP） guidance law for three-dimensional hypervelocity interception, so that the effect of the perturbation induced by seeker detection can be reduced. On the basis of a novel HP three-dimensional guidance model, a nonlinear variable structure guidance law is presented by using Lyapunov stability theory. The guidance law positions the interceptor ahead of the target on its tlight trajectory, and the speed of the interceptor is required to be lower than that of the target, A numerical example of maneuvering ballistic target interception verifies the rightness of the guidance model and the effectiveness of the proposed method.     

Differential-game-based guidance law using target orientation observations

Modern 4th generation air-to-air missiles are quite capable of dealing with today's battlefield needs. Advanced aerodynamics, highly efficient warheads and smart target acquisition systems combine to yield higher missile lethality than ever. However, in order to intercept highly maneuverable targets, such as future unmanned combat air vehicles (UCAV), or to achieve higher tracking precision for missiles equipped with smaller warheads, further improvement in the missile guidance system is still needed. A new concept is presented here for deriving improved differential-game-based guidance laws that make use of information about the target orientation, which is acquired via an imaging seeker. The underlying idea is that of using measurements of the target attitude as a leading indicator of target acceleration. Knowledge of target attitude reduces the reachable set of target acceleration, facilitating the computation of an improved estimate of the zero-effort miss (ZEM) distance. In consequence, missile guidance accuracy is significantly improved. The new concept is applied in a horizontal interception scenario, where it is assumed that the target maneuver direction, constituting a partial attitude information, can be extracted via processing target images, acquired by an imaging sensor. The derivation results in a new guidance law that explicitly exploits the direction of the target acceleration. The performance of the new guidance law is studied via a computer simulation, which demonstrates its superiority over existing state-of-the-art differential-game-based guidance laws. It is demonstrated that a significant decrease in the miss distance can be expected via the use of partial target orientation information.