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Performance of 3D TPN against true-arbitrarily maneuvering target for exoatmospheric interception

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Science China(Technological Sciences) 2018年第8期61卷 1161-1174页

作者： LI KeBo liang yangang SU WenShan CHEN Lei College of Aerospace Science and Engineering National University of Defense Technology National Innovation Institute of Defense Technology Academy of Military Science

True proportional navigation(TPN) guidance law is widely used for exoatmospheric interception, for its robustness and ease of implementation. The performance of TPN against nonmaneuvering target or the maneuvering target with a specific acceleration had been analyzed before. However, the obtained results are not suitable for the realistic exoatmospheric interception scenario,since the target may maneuver along an arbitrary direction with an arbitrary but upper-bounded acceleration in the threedimensional(3 D) space, which is the so-called "true-arbitrarily maneuvering target" in this paper. With the help of the line-ofsight(LOS) rotation coordinate system, the performance of 3 D TPN against the true-arbitrarily maneuvering target is thoroughly analyzed using the Lyapunov-like approach. The upper-bound of the 3 D LOS rate is obtained, and so is that of the commanded acceleration of 3 D TPN. After that, the capture region of 3 D TPN is presented on the initial relative velocity plane. The nonlinear3 D relative kinematics between the interceptor and the target is taken into full account. Finally, the new theoretical findings are demonstrated by numerical simulations.

关键词： exoatmospheric interception 3D TPN true-arbitrarily maneuvering target capturability Lyapunov-like approach

Impact Angle/Time Constraint Guidance Design Based on Fast Terminal Error Dynamics

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Journal of Shanghai Jiaotong university(Science) 2022年第6期27卷 823-832页

作者： QIN XUESHENG LIU YUANHE LI KEBO liang yangang College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China Human Key Laboratory of Intelligent Planning and Simulation for Aerospace Mission Changsha 410073China

Considering the problem that the optimal error dynamics can only converge at the terminal time,an impact angle/time constraint missile guidance law with finite-time convergence is designed in this paper,which is based on the pure proportional navigation(PPN)guidance law and the fast terminal error dynamics(FTED)*** missile guidance model and FTED equation are given first,and the dynamic equation of impact angle/time error based on PPN is also ***,the guidance law is designed based on FTED,and the guidance error can converge to 0 in a finite ***,considering the field of view constraint,the guidance law is improved by using the saturation function mapping ***,a numerical simulation example is given to verify the effectiveness of the guidance law,which shows that the guidance law proposed in this paper can make the missile quickly adjust to the desired states in advance,and effectively relieve the overload saturation pressure of the actuator.

关键词： design of guidance law fast terminal error dynamics field-of-view angle impact time impact angle

New Result on Interception of Stationary Targets at Arbitrary Time-Varying Speed

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Guidance, Navigation and Control 2022年第4期2卷 18-40页

作者： Yuanhe Liu Kebo Li yangang liang Jin Tang College of Aerospace Science and Engineering National University of Defense Technology Changsha 410072 P.R.China

This paper develops a novel approach and some main results on the varying-speed missile guided by pure proportional navigation(PPN)against a stationary target in the planar interception *** missile kinematic equation is established in the arc-length domain based on the differential geometry theory,which eliminates the influence of time-varying missile ***,the closed-form solutions of line-of-sight(LOS)rate,leading angle,closing speed,and curvature command are derived in the arc-length *** performance of the varyingspeed missile is analyzed,including the maximum relative distance,maximum curvature command,accurate path-to-go,and curvature ***,the capture region is obtained considering the missile maneuvering acceleration *** new theoretical results could be extended to improve the performance of existing guidance laws designed under the constant-speed assumption.

关键词： Differential geometry curve theory time-varying speed pure proportional navigation capture region

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空间碎片碰撞风险评估模型及其应用

国防科技大学学报 2017年第6期39卷 19-24页

作者：梁彦刚秦政国防科技大学空天科学学院湖南长沙410073

以现有的空间碎片环境模型为基础,建立了一套空间碎片风险评估模型。该模型包括空间碎片环境、航天器有限元建模、几何遮挡处理以及碰撞概率计算四个模块。为了验证风险评估模型的精度及有效性,针对机构间空间碎片协调委员会指定的三种... 详细信息

以现有的空间碎片环境模型为基础,建立了一套空间碎片风险评估模型。该模型包括空间碎片环境、航天器有限元建模、几何遮挡处理以及碰撞概率计算四个模块。为了验证风险评估模型的精度及有效性,针对机构间空间碎片协调委员会指定的三种标准工况,将该计算结果与国内外已有的风险评估模型的计算结果进行比较,验证了风险评估模型的正确性。利用开发的风险评估模型,对立方体航天器遭遇空间碎片碰撞风险进行仿真评估与分析,给出了轨道高度、倾角以及航天器自身的姿态参数对航天器遭遇空间碎片碰撞风险的影响特性。

关键词：空间碎片风险评估航天器几何遮挡

弹道导弹关机点状态估计的指数加权递归最小二乘方法

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国防科技大学学报 2014年第6期36卷 82-87页

作者：柴华梁彦刚唐国金国防科技大学航天科学与工程学院湖南长沙410073

在双星预警条件下,将指数加权递归最小二乘算法应用于目标关机点状态估计问题中。通过引入加权因子对目标助推段运动的局部拟线性特性进行描述,从而在一定程度上克服了一般的线性多项式模型难以准确刻画整个助推段运动的难题。通过对助... 详细信息

在双星预警条件下,将指数加权递归最小二乘算法应用于目标关机点状态估计问题中。通过引入加权因子对目标助推段运动的局部拟线性特性进行描述,从而在一定程度上克服了一般的线性多项式模型难以准确刻画整个助推段运动的难题。通过对助推段目标动力学特性的分析,考察了目标在垂直射面方向上的运动特性。在此基础上,提出了一种更为准确的助推段运动模型。仿真算例表明,所提出的关机点状态估计方法相对于传统的方法具有一定的优越性。

关键词：弹道导弹关机点状态指数加权递归最小二乘助推段模型

Research on the Approach to Assess Missile Operational Effectiveness Based on OPN

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微计算机信息 2007年第30期 6-8页

作者： LI JIUTIAN TANG GUOJIN liang yangang(College of Aerospace and Material Engineering,National U-niv.of Defense Technology,Changsha 410073,China)

Object Petri Net (OPN) which combines Petri net with object-oriented theory gives an effective method to use the Petri net in the field of M&S of Discrete Event Dynamic *** concept and mechanism of object is brought in,and the function of ba-sic Petri net is *** is a new idea to apply OPN to missile operational effectiveness assessment *** expanded func-tion of OPN is helpful for M&S of discrete missile combat *** kinds of stochastic factors of the combat are considered in the simulation,the assessment of operational effectiveness has high *** structure and the combat process of ICBM combat system are studied,and then the framework of OPN-based missile operational effectiveness assessment system and its operational mechanism are given.

关键词： object Petri net missile operational effectiveness framework

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在轨服务航天器任务指派问题

国防科技大学学报 2013年第5期35卷 26-30,51页

作者：梁彦刚王伟林国防科技大学航天科学与工程学院湖南长沙410073

一个在轨服务可有多种服务选择,必须进行合理的任务指派。首先求解服务航天器满足燃耗约束下的可达区域,筛选出满足可达范围要求的目标航天器。然后,以任务执行时间、燃料消耗和航天器服务优先级为优化目标,研究多目标的任务指派问题。... 详细信息

一个在轨服务可有多种服务选择,必须进行合理的任务指派。首先求解服务航天器满足燃耗约束下的可达区域,筛选出满足可达范围要求的目标航天器。然后,以任务执行时间、燃料消耗和航天器服务优先级为优化目标,研究多目标的任务指派问题。通过设计决策变量,考虑时间、燃耗等约束,建立了基于0-1整数规划的任务模型,采用NSGA-Ⅱ算法,求得问题的Pareto最优集,得到多组可供任务设计者选择自己偏好的折中方案。给出了两个多目标优化的仿真算例,算例一给出了任务指派的一般研究结论,算例二对比了另外一种算法:分层-加权法。仿真结果表明利用给出的方法可以较好地解决多目标下在轨服务任务指派问题。

关键词：在轨服务可达区域任务指派多目标整数规划 NSGA-Ⅱ

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采用状态转移矩阵的拦截中段制导方法

国防科技大学学报 2015年第4期37卷 137-142页

作者：柴华仲明梁彦刚国防科技大学航天科学与工程学院中国人民解放军69006部队

基于相对运动理论提出拦截中段制导方法。方法原理为,将拦截器初始轨迹与施加修正后的轨迹视为一主一从两空间目标,以相对运动理论描述从目标相对于主目标的运动规律,于是初始的修正量可由终点处相对状态求解。给出了一般形式的相对运... 详细信息

基于相对运动理论提出拦截中段制导方法。方法原理为,将拦截器初始轨迹与施加修正后的轨迹视为一主一从两空间目标,以相对运动理论描述从目标相对于主目标的运动规律,于是初始的修正量可由终点处相对状态求解。给出了一般形式的相对运动模型,运用几何法与变分法推导得到了J2摄动影响下相对运动的状态转移矩阵,在此基础上,提出了采用状态转移矩阵的拦截中段制导方法。仿真算例表明,提出的方法能够为工程实际中的拦截中段制导提供有效支持。

关键词：中段制导相对运动 J2摄动状态转移矩阵

Crosslinked Polyethyleneimine Gel Polymer Interface to Improve Cycling Stability of RFBs

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Energy Material Advances 2022年第1期2022卷 367-376页

作者： Hyung-Seok Lim Sujong Chae Litao Yan Guosheng Li Ruozhu Feng Yongsoon Shin Zimin Nie Bhuvaneswari Modachur Sivakumar Xin Zhang yangang liang David Jonathan Bazak Vaithiyalingam Shutthanandan Vijayakumar Murugesan Soowhan Kim Wei Wang Energy and Environment Directorate Pacific Northwest National LaboratoryRichlandWA 99354USA Physical&Computational Science Directorate Pacific Northwest National LaboratoryRichlandWA 99354USA

Redox flow batteries are considered a promising technology for grid energy ***,capacity decay caused by crossover of active materials is a universal challenge for many flow battery systems,which are based on various *** this paper,using the vanadium redox flow battery as an example,we demonstrate a new gel polymer interface(GPI)consisting of crosslinked polyethyleneimine with a large amount of amino and carboxylic acid groups introduced between the positive electrode and the *** GPI functions as a key component to prevent vanadium ions from crossing the membrane,thus supporting stable long-term *** voltammetry(CV)and electrochemical impedance spectroscopy(EIS)measurements were conducted to investigate the effect of GPI on the electrochemical properties of graphitic carbon electrodes(GCFs)and redox reaction of catholyte.X-ray photoelectron spectroscopy(XPS)and ^(1)H nuclear magnetic resonance(NMR)spectra demonstrated that the crosslinked GPI is chemically stable for 100 cycles without dissolution of polymers and swelling in the strong acidic *** from inductively coupled plasma mass spectrometry(ICP-MS),Fourier-transform infrared(FTIR)spectroscopy,and energy-dispersive X-ray(EDX)spectroscopy proved that the GPI is effective in maintaining the concentration of vanadium species in their respective half-cells,resulting in improved cycling stability because of it prevents active species from crossing the membrane and stabilizes the oxidation states of active species.

关键词： NMR vanadium swelling