Design of a CLOS guidance law via feedback linearization

An application of the feedback linearization technique to the design of a new command to line-of-sight (CLOS) guidance law for short-range surface-to-air missiles is described. The key idea lies in converting the three-dimensional CLOS guidance problem to the tracking problem of a time-varying nonlinear system. The result may shed new light on the role of the feedforward acceleration terms used in the conventional CLOS guidance laws. Through computer simulation, the effect of the dynamics of the ground tracker and the autopilot on the guidance performance of the new CLOS guidance law is investigated     

CLOS+IRTH composite guidance

A composite guidance scheme based on the command to line-of-sight (CLOS)+infrared terminal homing (IRTH) for a short-range surface-to-air missile system is proposed in an attempt to complement drawbacks of a single guidance law. Launch boundaries for a successful guidance handover are analyzed according to missile maneuverability and seeker gimbal angle limits. This paper also concentrates on developing practical guidance laws for the IRTH phase in the presence of inherent missile heading errors at the time of guidance handover and missile deceleration due to aerodynamic drag.     

反舰导弹自适应模糊滑模控制系统设计

针对反舰导弹的纵向过载控制系统设计问题,提出了一种自适应模糊滑模控制设计方法。将反演设计、模糊逻辑系统、自适应控制和滑模控制等方法结合,利用模糊逻辑系统估计被控系统的虚拟控制量;应用自适应设计方法逼近系统不确定项的未知上界;运用反演设计方法得到系统的虚拟控制量和实际控制量。基于Lyapunov稳定性理论,证明此闭环系统的所有误差信号均有界且指数收敛至原点的有界邻域内,仿真结果验证了该方法的有效性。     

考虑驾驶仪动态特性的固定时间收敛制导律

针对打击机动目标的制导问题，设计了一种同时考虑攻击角度约束、自动驾驶仪动态特性和固定时间收敛的新型制导律。首先，基于非奇异终端滑模控制和固定时间稳定性理论，采用反步递推方法设计制导律。在制导律设计过程中，设计了一种固定时间收敛的非奇异终端滑模面，基于固定时间控制和滑模控制，设计虚拟控制律，构造一种非线性一阶滤波器解决传统反步设计中的"微分膨胀"问题。基于超螺旋算法和固定时间稳定性理论，设计了一种固定时间收敛的滑模干扰观测器，用于估计目标机动等干扰。然后，基于Lyapunov稳定性理论，对制导律的固定时间稳定性进行了证明，并给出了收敛时间的表达式。最后，通过仿真分析，验证了所提制导律的有效性，和现有制导律相比，所提制导律具有较高的制导精度和角度约束精度、较快的系统收敛速度以及较少的能量消耗。     

基于蛇行变轨的反舰导弹末制导律研究

提出了一种超声速反舰导弹针对海面机动目标的主动蛇行变轨导引设计方案。首先建立了反舰导弹、拦截弹和舰艇在航向平面的运动几何关系模型,然后基于Terminal滑模控制的思想进行了制导律设计,采用约束视线角和视线角速度的方法使反舰导弹在打击舰艇的过程中实现蛇行变轨,以能够规避敌方拦截导弹。仿真结果表明,该制导律具有期望的性能要求。     

Guidance laws for attacking defended target

In this paper, two new guidance laws based on differential game theory are proposed and investigated for the attacker in an attacker-defender-target scenario.The conditions for the attacker winning the game are analyzed when the target and defender using the differential game guidance law based on the linear model.The core ideas underlying the two guidance laws are the attacker evading to a critical safe boundary from the defender, and then maintaining a critical miss distance.The guidance law more appropriate for the attacker to win the game differs according to the initial parameters.Unlike other guidance laws, when using the derived guidance laws there is no need to know the target and the defender's control efforts.The results of numerical simulations show that the attacker can evade the defender and hit the target successfully by using the proposed derived guidance laws.     

Design of Time-constrained Guidance Laws via Virtual Leader Approach

Guidance problems with flight time constraints are considered in this article. A new virtual leader scheme is used for design of guidance laws with time constraints. The core idea of this scheme is to adopt a virtual leader for real missiles to convert a guidance problem with time constraints to a nonlinear tracking problem, thereby making it possible to settle the problem with a variety of control methods. A novel time-constrained guidance (TCG) law, which can control the flight time of missiles to a prescribed time, is designed by using the virtual leader scheme and stability method. The TCG law is a combination of the well-known proportional navigation guidance(PNG) law and the feedback of flight time error. What's more, this law is free of singularities and hence yields better performances in comparison with optimal guidance laws with time constraints. Nonlinear simulations demonstrate the effectiveness of the proposed law.     

A finite-time 3D guidance law based on fixed-time convergence disturbance observer

In order to achieve accurate interception of high-speed maneuvering targets, this paper presents a relative Line-of-Sight (LOS) velocity based finite-time three-dimensional guidance law design framework, and discusses the application of fixed-time convergence disturbance observer in this framework. Firstly, a simple Lyapunov function is provided to show that the coupled terms in the relative kinematics can be ignored in the proposed guidance law design framework. Secondly, the realizations of several classical guidance laws are analyzed with the proposed framework, including TPN guidance law, finite-time Input-to-State Stability (ISS) guidance law, and sliding mode guidance law. Thirdly, fixed-time convergence disturbance observers are introduced to design the composite finite-time 3D guidance law, and Lyapunov method is employed to show the stability of the guidance system. Numerical simulations with different scenarios show that the proposed generalized guidance law performs high interception accuracy.     

导弹块对角控制器的组合设计法

利用小脑关节模型控制器 ( CMAC)神经网络辨识了导弹控制系统的几个重要空气动力参数,证明了估计误差、权误差有界,然后用解析逆解设计方法、模糊神经网络变结构控制方法设计了块对角控制器。仿真结果显示了该算法的有效性。     

导弹复合控制系统的模糊逻辑控制分配

针对空空导弹复合控制系统中的控制分配问题,提出了一种模糊逻辑控制分配算法。采用动态面控制方法设计了复合控制量的控制律。在设计过程中,利用扩张状态观测器估计汇总不确定项,并采用光滑二阶滑模控制算法设计了控制律,达到了提高鲁棒性和削弱抖振现象的目的。应用模糊逻辑控制分配算法将复合控制量分解为直接力控制指令和舵偏角控制指令。为了检验所设计的复合控制系统的控制效果,对采用基于模糊逻辑控制分配算法的复合控制系统和传统的气动力控制系统进行了对比仿真实验。仿真结果表明,所设计的复合控制系统具有更好的控制效果。     

一种改进的最优制导律及其仿真研究

高速再入飞行器通常具有末制导系统，为保证末制导系统的正常工作，制导律的设计不但要保证末端制导精度，还要使飞行器以一定的速度到目标，提出了一种改进的最优制导律设计方法，得到了可以保证末端速度方向的制导律，速度大小控制通常靠理想速度曲线来保证，按一定的规则将最优制导律与理想速度曲线结合起来就得到了满足全部要求的制导律。仿真结果表明：所提出的改进的最优制导律是合理、有效的。     

Three-dimensional guidance law based on adaptive integral sliding mode control

For the terminal guidance problem of missiles intercepting maneuvering targets in the three-dimensional space, the design of guidance laws for non-decoupling three-dimensional engage-ment geometry is studied. Firstly, by introducing a finite time integral sliding mode manifold, a novel guidance law based on the integral sliding mode control is presented with the target acceler-ation as a known bounded external disturbance. Then, an improved adaptive guidance law based on the integral sliding mode control without the information of the upper bound on the target accel-eration is developed, where the upper bound of the target acceleration is estimated online by a designed adaptive law. The both presented guidance laws can make sure that the elevation angular rate of the line-of-sight and the azimuth angular rate of the line-of-sight converge to zero in finite time. In the end, the results of the guidance performance for the proposed guidance laws are pre-sented by numerical simulations. Although the designed guidance laws are developed for the con-stant speed missiles, the simulation results for the time-varying speed missiles are also shown to further confirm the designed guidance laws.     

一种基于李群方法的新型三维制导律设计

使用李群方法设计了一种新型三维制导律。在俯仰、偏航通道之间存在强耦合关系时,基于双通道解耦的假设构造三维制导律变得困难,而基于李群方法则可以在不进行通道解耦的条件下进行制导律设计。本文首先基于矢量建立了三维制导的一般运动学模型,在给出了矢量的SO(3)群描述之后,按照SO(3)群上的广义比例 微分(PD)控制方式进行了制导律设计。所得到的三维制导律既能用于目标机动的制导,也能用于有终端约束的制导。该制导律在二维平面的简化结果与传统比例导引的结果一致。最后用典型飞行轨迹仿真验证了其可行性和良好的性能。     

Three-dimensional Large Landing Angle Guidance Based on Two-dimensional Guidance Laws

 Both the design process and form of the three-dimensional (3D) suboptimal guidance law (3DSGL) are very complex. Therefore, we propose the use of two-dimensional (2D) guidance laws to meet the guidance requirements of 3D space. By analyzing the relationship between the flight-path angle and its projections on OXY and OXZ planes, we obtain the ideal design requirements of the guidance laws. Based on the requirements, we design a 2D suboptimal guidance law used in the horizontal plane; combining the 2D vertical suboptimal guidance law, we create a whole ballistic simulation of six degree-of-freedom. The results are compared with those using other three guidance modes in the case of large windage of the initial azimuth angle. When the proportional navigation guidance (PNG) law is used in the horizontal planes, the landing angle will obviously decrease. With the proposed guidance mode, the large landing angle can be realized and meet the guidance precision requirements. Moreover, the required overload can decrease to meet the control requirement. The effects of the proposed guidance mode are close to that of 3DSGL despite its very simple form.     

Finite-time composite guidance law with input constraint and dynamics compensation

Guidance laws are proposed for a near space interceptor with on–off type thrust as output. The target-interceptor engagement kinematics is integrated with the first-order dynamics of thruster to design guidance laws. The bang-bang type guidance law with linear sliding mode is proposed to deal with thruster dynamics, and the sufficient condition for finite time convergence is rigorously proved based on the finite-time convergence theory. According to the sufficient condition, a sliding mode guidance law with hysteresis-band switching is introduced to reduce the switching frequency of thruster. Then two guidance laws are combined into a composite guidance law to improve the guidance performance. Simulation results show that the line-of-sight angular rate can converge to a neighborhood of the equilibrium point before the final time of the guidance process, and the composite guidance law has better performance than typical guidance laws.     

变结构控制在导弹制导中的应用综述

简要介绍了变结构控制理论和导弹制导律，对基于变结构控制的导弹制导律进行了比较详细的研究。重点介绍了各种制导律中滑模面的选择和制导律的设计，并给出了一些仿真结果。研究表明，由于变结构控制的应用．使得制导律具有很强的鲁棒性，比传统的比例导引律有更多的优越性。     

考虑运动耦合的BTT导弹三维制导律设计

针对倾斜转弯(BTT)导弹制导过程中的双通道耦合问题,设计了一种新型三维(3D)制导律。首先,通过矢量描述的方式,将导弹运动学模型分解成俯冲、转弯和耦合3项,俯冲和转弯两项在笛卡儿坐标系下描述,耦合项则在SO(3)空间中描述。然后,针对无终端约束和有终端约束情况,分别采用比例控制和SO(3)群上的广义比例-微分(PD)控制方式进行了相应的制导律设计。所得制导律既克服了李群方法的结构复杂性,又避免了解耦方法的信息损失。仿真表明,所设计的制导律能够满足BTT导弹精确制导的要求。     

短距起飞垂直着陆推力矢量无人飞行器减速过渡控制律设计

为实现短距起飞垂直着陆(STOVL)无人飞行器在推力矢量控制下的减速过渡,研究减速过渡阶段的控制律综合设计方法.首先通过分析STOVL无人飞行器减速过渡性能,对减速过渡推力矢量控制方案进行了评估;然后采用隐式动态逆方法设计导引律,为STOVL无人飞行器按预设任务减速过渡提供可达的控制指令;最后采用改进的特征结构配置方法进行内环控制律设计,跟踪导引指令并保持姿态稳定,伴随动压降低加入姿态喷管控制,辅助气动舵面稳定姿态.由全量六自由度飞行仿真结果表明:当减速过渡速度低于最小平飞速度以后,STOVL无人飞行器依然保持良好的航迹跟踪和姿态稳定.该方法完全采用直接配置法,有利于随控布局总体方案的快速评估.      

基于自适应滑模与模糊控制的导弹直接力/气动力复合控制系统优化设计

 针对导弹直接力/气动力复合控制问题,提出了一种基于自适应滑模控制(ASMC)与模糊逻辑的自动驾驶仪设计方法。该方法将整个导弹控制系统分为气动力控制子系统(ACS)和直接力控制子系统(RCS)两部分。前者采用自适应滑模控制理论进行设计,利用其所具有的强鲁棒性优点,克服了包括参数摄动与外界扰动在内的各类不确定性因素的影响。后者通过基于规则的模糊推理来确定不同条件下直接力作用的大小,以辅助提高气动力子系统的性能。在控制系统结构确定的条件下,利用遗传算法(GA)对各参数进行优化,实现了两个子系统之间的协调工作。仿真结果表明,所提出的控制方案对机动指令具有较好的跟踪效果,适用于直接力/气动力复合控制导弹的控制系统设计。     

机翼摇晃预测与抑制

将分支分析与突变理论方法(BACTM)和模糊逻辑控制(FLC)方法相结合,形成BACTM-FLC方法,实现飞机大迎角下的动力学特性分析和模糊控制律设计一体化。在对某大后掠角三角翼的非线性动力学特性进行预测分析的基础上,设计了模糊控制器抑制机翼摇晃,用BACTM对该模糊控制器的控制效能进行评估分析,并对BACTM的预测与评估结果进行了仿真验证。结果表明,BACTM-FLC方法可以全局性地预测和分析飞机的大迎角非线性动态特性,并对其进行有效控制。