Optimal guidance for acceleration constrained missile andmaneuvering target

Explicit formulas of optimal guidance laws for an acceleration-constrained, arbitrary-order missile and maneuvering target are derived. These formulas are given in terms of the transfer function and acceleration constraint of the missile and the transfer function/shaping filter of the target. Optimal full-state feedback guidance law is synthesized against a target performing a barrel roll maneuver, and compared with the performance of proportional navigation (PN) for minimum and nonminimum phase missile. Simulation of a third-order missile shows the relative gain from using the full-order guidance law     

自寻的导弹攻击机动目标的最优制导规律的研究及实现

提出一种适用于红外和雷达自寻的制导导弹的适应性强、制导精度高、易实现的最优制导规律。为解决工程实现的关键问题,提出了目标机动加速度模型。根据该模型并利用导弹导引头的AGC信号或雷达测距信号,给出了目标机动加速度、导弹与目标相对距离和距离变化率的估计算法。     

Optimal and Suboptimal Guidance for a Short-Range Homing Missile

Optimal and suboptimal guidance laws for short-range homing missiles are developed and compared to the commonly mechanized quidance law of proportional navigation. The optimal controller is derived as an optimal feedback regulator; the suboptimal controller is an approximation of the optimal regulator and consists of timevarying proportional navigation plus a time-varying gain term times a calculated target acceleration. Monte Carlo studies of the three controllers show that the optimal and suboptimal controllers are much superior to proportional navigation for the case of combined constant target acceleration, line-of-sight rate noise, and missile acceleration saturation.     

Saturated super-twisting sliding mode missile guidance

This paper concentrates on developing a missile terminal guidance law against a highly maneuvering target whose maneuvering acceleration is very close to that of the missile or even exceeds the missile normal acceleration in a finite period of time. A new saturated super-twisting algorithm is proposed and applied to the design of missile guidance law. The proposed algorithm has the advantages of simple structure, easy parameter tuning rules and a full utilization of the limit control input. The designed saturated super-twisting sliding mode guidance law is then employed in a missile guidance system. Simulation and its superior performance against strong maneuvering targets is demonstrated.     

空-空导弹全向攻击最优制导规律研究

 将发射瞬时所确定的平行接近弹道作为基准弹道,由于各种干拢所引起的相对于基准弹道的偏离作为偏差来处理;用最优控制理论导出空-空导弹进行全向攻击的最优制导律,此制导律包含目标加速度反馈。当目标作非机动飞行时,最优制导律是一种变比例系数的比例制导。数字仿真结果表明:在相同条件下,最优制导弹道需用过载、终端脱靶量均小于比例制导,特别是从目标前方攻击时,其制导精度大大优于比例制导。     

Discrete optimal guidance for high-order missile and maneuvering target

An explicit closed-form formula of a discrete guidance law for a linear time-invariant, acceleration commanded, arbitrary-order missile and a linear, time-invariant arbitrary-order, maneuvering target is derived. The formula is given in terms of the missile and target transfer functions and responses to initial conditions. Examples are explicitly solved for zero-lag and a first-order missile. As an example, it is shown that the discrete proportional navigation ratio is higher than 3 and time varying in contrast to the continuous case.<>     

True proportional navigation with maneuvering target

We analytically obtain the capture regions for the true proportional navigation (TPN) missile guidance law against an intelligently maneuvering target. Two versions of TPN are considered. The first is the original TPN which assumes the commanded lateral acceleration to be directly proportional to the line-of-sight (LOS) rate only, the proportionality factor being an arbitrary constant or dependent only on the initial closing velocity. The other, known as RTPN (realistic TPN), assumes the commanded lateral acceleration to be directly proportional to the LOS rate and also the current closing velocity. The target is assumed to maneuver in such a way as to increase the LOS rate and thus directly oppose the proportional navigation (PN) philosophy of annulling the LOS rate. A necessary and sufficient condition for capture is derived for the original TPN, and using it, the exact capture region is obtained. A sufficient condition for capture is derived for RTPN and is used to obtain its capture region partially. Some necessary conditions for capture are also derived for RTPN and are used to obtain an upper bound on its complete capture region. Using these conditions some important results on the existence of capture regions and a comparative study of capturability of TPN laws are also presented     

一种攻击大机动目标的变参数组合导引律

针对目标作大机动时的导引问题,提出了一种既简单又有效的比例加变结构组合导引律,给出了其设计机理,并在理论上对变参数进行了优化设计。通过仿真结果比较,验证了此组合导引律可以在固定时间内明显地减少追踪者的脱靶量。     

自适应严格收敛非奇异终端滑模制导律

针对机动目标的末制导拦截问题，设计了一种带终端角度约束的有限时间收敛终端滑模制导律。首先，分析了现有非奇异终端滑模制导律存在的滑模面不能严格有限时间收敛的问题，进而构造了一种新型的非奇异终端滑模面。其次，设计了一种对目标机动上界的自适应估计，提出了一种自适应严格收敛非奇异终端滑模制导律的设计方法。最后，基于Lyapunov稳定性理论，证明了设计的制导律能够使得制导系统在有限时间内收敛到零，并且保证了滑模面在收敛过程中不存在非收敛因子，是严格有限时间收敛的。仿真实验验证了该制导律能够有效地拦截机动目标，同时和与现有的非奇异终端滑模制导律以及基于转换滑模面的非奇异制导律相比，拦截时间更短，终端攻击角度精度更高，导弹机动消耗的能量更少。     

现实真比例导引拦截任意机动目标捕获区域

主动机动突防技术的发展给大气层外动能拦截带来了严重困难。假设目标机动加速度方向垂直于弹目视线、形式任意且有界，分析了用于大气层外拦截制导的现实真比例导引律（RTPN）对该任意机动目标的捕获区域。首先在考虑拦截器存在机动过载饱和限制的情况下，推导了比例导引系数的选择范围，可使RTPN的制导指令加速度在拦截过程中不超过拦截器饱和过载；其次基于不等式分析方法，在不考虑拦截器过载限制时，推导了RTPN对任意机动目标的捕获区域；然后结合拦截器机动过载限制，推导了RTPN对任意机动目标的更加实用的捕获区域；最后通过数值仿真算例，验证了所提出的理论。     

Cooperative guidance of seeker-less missile considering localization error

To perform an accurate fire-and-forget attack of seeker-less missile with the consideration of the localization error, a new cooperative guidance strategy of multi-missiles is proposed in this work. Firstly, an estimated position of the seeker-less missile is carefully selected, based on which the slant angle of the line between the estimated and real positions of the seeker-less missile is approximately derived inspired by the localization theory of GPS(Global Position System).Then, respectively based on the guidance law considering the impact angle and time constraints, the consensus theory and the finite-time convergence approach, three cooperative guidance laws employing the previously obtained slant angle are derived for intensive attack to address either a stationary or maneuvering target. Simulation results well demonstrate the effectiveness and advantages of the proposed cooperative guidance strategy.     

反舰导弹最优滑模制导律仿真研究

针对传统比例导引法攻击机动目标的不足,建立了三维空间中反舰导弹和目标的相对运动模型,在研究反舰导弹攻击非机动目标的最优制导律基础上,利用俯仰和偏航两个平面相叠加的方法,结合滑模控制理论设计了工程上易于实现的三维模型下的反舰导弹最优滑模制导律。仿真结果表明,给出的导引律在攻击机动目标时制导精度高、脱靶量小,导引控制过程具有良好的动态性,性能明显优于传统的比例导引律。     

An Adaptive Weighted Differential Game Guidance Law

For intercepting modern high maneuverable targets, a novel adaptive weighted differential game guidance law based on the game theory of mixed strategy is proposed, combining two guidance laws which are derived from the perfect and imperfect information pattern, respectively. The weights vary according to the estimated error of the target’s acceleration, the guidance law is generated by directly using the estimation of target’s acceleration when the estimated error is small, and a differential game guidance law with adaptive penalty coefficient is implemented when the estimated error is large. The adaptive penalty coefficients are not constants and they can be adjusted with current target maneuverability. The superior homing performance of the new guidance law is verified by computer simulations.     

神经网络最优闭环制导律设计

对于复杂的非线性导弹制导系统 ,很难求得其解析的最优制导律 ,只能求得开环的数字解 ,不能适用于具有时变不确定性的导弹制导系统。利用神经网络的学习和推广能力 ,对开环的数字最优制导律进行离线的学习 ,作为闭环的神经最优制导律在线应用。研究分别选择系统状态变量和视线角速率等不同的神经网络输入对制导系统性能的影响 ,以及各种制导律的鲁棒性问题 ,并采用模块化神经网络结构提高神经网络的学习和推广能力 ,仿真结果得到一些有益的结论。     

Performance analysis of PNG laws for randomly maneuvering targets

The performance of the conventional proportional navigation guidance (PNG) law for a randomly maneuvering target is considered. By means of the Lyapunov method, it is proved that an ideal missile guided by the conventional PNG law can always intercept a target which maneuvers with time-varying normal acceleration provided that the navigation constant is sufficiently large. The authors also propose a modified PNG (MPNG) law which seems to improve the performance of the conventional PNG law at the final phase of pursuit. Simulation results demonstrate that the MPNG law demands less missile acceleration at the final phase of pursuit than the conventional PNG law     

Three-dimensional adaptive finite-time guidance law for intercepting maneuvering targets

To intercept maneuvering targets at desired impact angles, a three-dimensional terminal guidance problem is investigated in this study. Because of a short terminal guidance time, a finitetime impact angle control guidance law is developed using the fast nonsingular terminal sliding mode control theory. However, the guidance law requires the upper bound of lumped uncertainty including target acceleration, which may not be accurately obtained. Therefore, by adopting a novel reaching law, an adaptive sliding mode guidance law is provided to release the drawback. At the same time, this method can accelerate the convergence rate and weaken the chattering phenomenon to a certain extent. In addition, another novel adaptive guidance law is also derived; this ensures systems asymptotic and finite-time stability without the knowledge of perturbations bounds.Numerical simulations have demonstrated that all the three guidance laws have effective performances and outperform the traditional terminal guidance laws.     

Empirical virtual sliding target guidance law design: an aerodynamic approach

We present a novel empirical virtual sliding target (VST) guidance law for the midcourse phase of a long range surface-to-air missile that uses the simplicity of the conventional proportional navigation (PN) guidance law while exploiting the aerodynamic characteristics of a missile's flight through the atmosphere to enable the missile to achieve superior performance than that achieved by conventional PN guidance laws. The missile trajectory emulates the trajectory of an optimal control based guidance law formulated on a realistic aerodynamic model of the missile-target engagement. The trajectory of the missile is controlled by controlling the speed of a virtual target that slides towards a predicted intercept point during the midcourse phase. Several sliding schemes, both linear and nonlinear, are proposed and the effect of the variation of the sliding parameters, which control the sliding speed of the virtual target, on the missile performance, are examined through extensive simulations that take into account the atmospheric characteristics as well as limitations on the missile in terms of the energy available and lateral acceleration limits. Launch envelopes for these sliding schemes for approaching and receding targets are also obtained. These results amply demonstrate the superiority of the proposed guidance law over the conventional PN law.     

过载约束下的大机动目标协同拦截

研究了非线性拦截几何下具有过载约束的多枚弱机动能力的导弹拦截强机动能力的目标的协同拦截问题。首先，在建立导弹的可达域、导弹的可行域以及目标的逃逸域这3个概念的基础上提出了非线性拦截几何下的基于逃逸域覆盖的协同拦截策略，并提出了基于标准弹道的设计方法。然后，给出了协同拦截制导律的形式，研究了导弹的末制导初始阵位、制导律参数以及导弹对目标机动的覆盖区域这三者间的关系，并设计了数值求解算法来实现对多弹的覆盖区域的分配、协同制导律的设计以及多弹初始拦截阵位的配置。最后，对理论结果进行仿真。结果显示，多枚机动性较小的导弹，通过初始拦截阵位的合理配置和协同拦截制导律的合理设计，可以实现对机动性能较强的目标的协同拦截。     

Robust guidance for electro-optical missiles

A robust guidance law is presented which renders zero miss distance (ZMD) against deterministically or randomly maneuvering targets for all missile parametric uncertainties. Since the resulting guidance controller is a phase-lead network, it is mainly suitable for systems characterized by moderate glint levels such as electro-optical missiles. The structured uncertainties in missile dynamics are modeled by interval transfer functions. It is first shown that for the nominal case, when the total missile transfer function is positive real, ZMD can be obtained. When uncertainties are considered, the problem becomes design of a guidance controller which renders a family of transfer functions positive real. A new algorithm for the design of such controllers is proposed. An example illustrating a typical design procedure for a nonlinear real-life missile model is given, showing the simplicity and effectiveness of the proposed robust guidance. The main conclusion of this work is that the newly developed guidance law performs well against highly maneuvering targets and may be a suitable alternative to optimal guidance laws in low-glint systems.     

一种瞬时圆周加速度制导律设计

为了保证导弹攻击目标的精确性,根据平面弹道的几何特性,设计了一种输出指令为过载的瞬时圆周制导律.描述了瞬时圆周加速度制导律原理,详细推导了制导方程.利用导弹质心和目标质心的位置及速度信息,得出导弹攻击目标的过载制导指令,并进行了弹道仿真.仿真结果表明,所设计的瞬时圆周加速度制导律不仅能够保证导弹准确命中目标,而且弹道平...