Study of the Lift Force Induced by An Interceptor on A High-Speed Mono-Hull:The Affecting Factors and Estimation Formula

To find a better way to estimate the lift force induced by an interceptor on a high-speed mono-hull ship,a series of high-speed mono-hull ship models are designed and investigated under different conditions.Different lift forces are obtained by numerical calculations and validated by a model test in a towing tank.The factors that influence the force are the interceptor height,velocity,draft,and deadrise angle.The relationship between each factor and the induced lift force is investigated and obtained.We found that the induced lift mainly depends on the interceptor height and advancing velocity,and is proportional to the square of the interceptor height and velocity.The results also showed that the effects of the draft and deadrise angle are relatively less important,and the relationship between the induced lift and these two factors is generally linear.Based on the results,a formula including the combined effect of all factors used to estimate the lift force induced by the interceptor is developed based on systematic analysis.The proposed formula could be used to estimate the lift force induced by interceptors,especially under high-speed condition.

Design and Analysis of Terminal Guidance Law for Kinetic Interceptors based on Pulse Engine

A new terminal guidance law is proposed based on a solid propellant pulse engine and an improved proportional navigation method to address the terminal guidance issue for kinetic interceptors.On this basis,the start-stop curve of the pulse motor during the terminal guidance process is designed,along with its start-up logic.The effectiveness of the proposed guidance strategy is verified through simulation.

ADAPTIVE PREDICTIVE CONTROL OF NEAR-SPACE VEHICLE USING FUNCTIONAL LINK NETWORK

A novel nonlinear adaptive control method is presented for a near-space hypersonic vehicle （NHV） in the presence of strong uncertainties and disturbances. The control law consists of the optimal generalized predictive controller （OGPC） and the functional link network （FLN） direct adaptive law. OGPC is a continuous-time nonlinear predictive control law. The FLN adaptive law is used to offset the unknown uncertainties and disturbances in a flight through the online learning. The learning process does not need any offline training phase. The stability analyses of the NHV close-loop system are provided and it is proved that the system error and the weight learning error are uniformly ultimately hounded. Simulation results show the satisfactory performance of the con- troller for the attitude tracking.

Adaptive functional link network control of near-space vehicles with dynamical uncertainties

The control law design for a near-space hypersonic vehicle（NHV） is highly challenging due to its inherent nonlinearity,plant uncertainties and sensitivity to disturbances.This paper presents a novel functional link network（FLN） control method for an NHV with dynamical thrust and parameter uncertainties.The approach devises a new partially-feedback-functional-link-network（PFFLN） adaptive law and combines it with the nonlinear generalized predictive control（NGPC） algorithm.The PFFLN is employed for approximating uncertainties in flight.Its weights are online tuned based on Lyapunov stability theorem for the first time.The learning process does not need any offline training phase.Additionally,a robust controller with an adaptive gain is designed to offset the approximation error.Finally,simulation results show a satisfactory performance for the NHV attitude tracking,and also illustrate the controller＇s robustness.

Analysis on Attenuation Efficiency of Lightning Current by Lightning Interceptor

Lightning interception technology is one of the three core technical systems of regional lightning protection theory.Among them,the omni-directional multi-pulse lightning interceptor(hereinafter referred to as lightning interceptor,the same below)has the ability to attenuate lightning current≥40%and significantly reduce the intensity of the spatial electromagnetic field around the lightning point.In order to explore the attenuation mechanism and effect of lightning interceptor to lightning current,this paper analyzed a lightning stroke process at 16:00 on August 19,2022,and tried to explain the attenuation effect of lightning interceptor to lightning current with the physical parameters of lightning stroke.

Prospect of Near-Space Exploration and Scientific Experiment Carrier Platform Demand

It is an important scientific research activity in China to carry out near-space exploration and scientific experiments via aerospace carriers.Early near-space exploration projects mainly used aircraft,balloons,sounding rockets and Earth satellites to carry out space environment exploration.With the development of China’s space science and technology,microgravity science has become a frontier science that has developed rapidly in the past 20 years.With the continuous progress of national space science and technology,the demand for near-space exploration and scientific experiments is increasing year by year.In the next 2 to 3 years,many advanced science activities and the associated technologies need to conduct corresponding experimental research work.This paper mainly analyzes the significance of scientific research and the ways to realize near-space exploration at home and abroad,and analyzes the directions and innovations that can be carried out in the future.

基于新型非线性函数的动能拦截器自抗扰姿态跟踪控制

针对动能拦截器在开展空间拦截任务时,对姿态控制系统快速性、准确性和鲁棒性的极高要求,提出了一种新型自抗扰控制方法.建立了动能拦截器姿态动力学模型,并将其转换为姿态跟踪误差二阶状态方程;基于自抗扰控制器中小误差大增益、大误差小增益的思想,设计了一种新型的非线性函数;基于该非线性函数,设计了一种新型的跟踪微分器,并且优化了扩张状态观测器和非线性控制器.将指定时间收敛的预设性能函数作为跟踪微分器的期望信号,可实现姿态误差按照预设性能函数收敛到期望值,且收敛时间可预先确定.利用伪速率(pseudo rate,PSR)脉冲调制器对连续控制力矩进行脉冲调制.数值仿真结果表明本文设计的控制方法具有较高的姿态控制精度,在面临环境扰动时具有较好的鲁棒性.

基于SSM框架图书借阅管理系统的研究与实现

基于SSM(Spring+spring MVC+Mybatis)框架研究并实现了一个图书借阅管理系统,前台页面使用当前主流的BootStrap和jQuery框架实现,通过配置拦截器对用户访问的路径进行判断,以实现权限控制。实现程序有很好的可移植性、兼容性、可扩展性以及数据处理的高效性。

单体高速船截流板减阻的浅水特性分析

[目的]为探究水深对截流板减阻效果及最佳减阻高度的影响,基于RANS方程组数值求解的方法,对加装不同高度截流板的单体高速船进行深浅水绕流场数值模拟。[方法]首先,以DTMB 5415光体高速船为研究对象进行数值方法的有效性验证与不确定度分析;然后,对不同截流板高度与水深工况下的某高速单体船进行绕流场数值模拟;最后,基于数值结果分析不同工况的阻力、航态及流场特性。[结果]研究表明,截流板的减阻效果存在明显的浅水效应;最佳减阻高度随水深变化基本不变,截流板对纵倾角度的降低也基本不随水深的变化而改变;截流板有一定降低船后兴波的作用,但随着水深的减小,该作用效果会减弱。[结论]所做研究对截流板在浅水中的应用具有一定的参考价值。

阻流板对规则波中船舶阻力及运动特性影响研究

[目的]旨在分析阻流板对规则波中船舶阻力及运动特性的影响。[方法]以一条半排水型方尾船为研究对象,基于RANS方法并结合重叠网格技术进行阻流板安装前后船舶在规则波中的阻力与运动特性数值仿真,总结船舶阻力、姿态与运动响应随波长与航速的变化规律。[结果]结果表明:阻流板在规则波中的减阻率比静水减阻率大1.03%~2.43%;阻流板对垂荡和纵摇传递函数的影响随着波长的增大而变大,λ=2L_(PP)工况下的垂荡传递函数T_(F3)和纵摇传递函数T_(F5)平均降低了3.5%和1.4%;当船舶出现甲板上浪时,阻流板可使T_(F3)和T_(F5)的降低率分别达到9%和3%。[结论]研究方法与研究成果可为船舶节能装置设计与性能预报提供技术参考。

美国KEI导弹发展研究及性能分析

动能拦截弹(kinetic energy interceptor,KEI)主要用于拦截在助推段、上升段以及中段飞行的中远程和洲际弹道导弹,具有高速、高加速的特点。通过文献资料的研究分析和建模仿真,对KEI导弹的总体参数、气动参数、动力参数进行了反设计和研究,并对KEI导弹的飞行性能和拦截性能进行了仿真,结果表明:KEI导弹能够在约60 s内加速至6 km/s,并对典型目标具备在助推段/上升段拦截弹道导弹的能力,对国内拦截武器的发展和研究具有参考意义。

海基中段反导拦截舰配置方法研究

为发挥海基反导力量的机动性,拓展弹道导弹防御层次,对中段拦截舰配置方法进行研究。建立拦截弹和目标弹道模型,以美军“标准-3”拦截弹参数为依据对拦截弹空间杀伤区进行仿真;基于拦截舰机动性特点和中段反导“迎头撞击”的要求,分析拦截约束条件和拦截舰配置位置评价指标;以3500 km射程目标为例,仿真分析了拦截舰不同配置位置下的拦截能力,进而给出相应的配置方法。所得结论可为海基中段反导兵力配置提供参考。

一种分布式协同拦截制导方法及半实物仿真验证

针对考虑速度大范围时变的多拦截弹集群协同拦截问题,提出了一种基于距离协同的、可自由配置弹间通信数量的分布式协同制导方法。其中,基于扩张函数将弹目距离协同转化为期望速度前置角的求解,能够更好地适应拦截弹大范围速度变化,结合比例导引设计了动态逆控制器实现对期望速度前置角的有效跟踪。同时构建了集群半实物仿真系统,在三种不同场景下进行了集群半实物仿真试验。试验结果表明,本文所提算法能够有效提高多拦截弹集群的同时命中效果,验证了协同制导算法的有效性和鲁棒性。

随机海况下自控式截流板减纵摇研究

文中针对过渡型艇减纵摇问题以某过渡型艇为对象,建立随机海浪模型,基于势流理论得到波浪干扰模型和船舶运动模型,并结合CFD方法计算得到的目标艇的截流板升力和升力矩模型,设计了PID控制器和滑模鲁棒控制器,分别搭建开环和闭环控制系统,并对运动计算结果进行比较.在实际约束条件下,分别采用两种控制器的闭环系统相较于开环系统都展现出不同程度的减纵摇能力,其中采用滑模控制器时,三级海况下纵摇幅值可减小34%,五级海况下亦可达到8%.自控式截流板减纵摇系统能够有效减小过渡型艇的纵摇运动,滑模鲁棒控制器在三级海况下比PID控制器更优,在四、五级海况下也有良好的减摇效果.

豪华邮轮全船线型优化及截流板设计

为了降低航行阻力,满足豪华邮轮营运经济性的需求,对某8万总吨级豪华邮轮进行了基于阻力性能的全船线型优化及截流板设计。首先,结合CAESES的半参数化变形和SHIPFLOW的势流计算方法,针对目标船进行了兴波阻力最小化的线型优化,再对典型优化方案采用STAR-CCM+计算粘流总阻力,评估优化效果;其次,针对优化的船型方案进行了截流板的设计,进一步降低船型总阻力;最后,通过模型试验验证优化效果。试验结果显示,优化线型安装优选截流板后相对于原型实船有效功率下降了7.8%,证明了所采用的豪华邮轮线型优化和截流板设计方法的可行性。

INTERCEPT OPTIMIZATION OF EXO-ATMOSPHERIC INTERCEPTOR BASED ON GENETIC ALGORITHM

An intercept optimization approach of the exo-atmospheric interceptor is proposed by the middle and terminal flight stages. Firstly, the dynamic models of the exo-atmospheric interceptor in middle and terminal flight stages are constructed ; and the velocity gain midcourse guidance law and the robust variable structure terminal guidance law are designed. Then the optimization parameters and their constraints affecting the intercept performance are determined. The genetic algorithm （GA） with the advantage of global optimization is used to deal with the intercept optimization problem. The performance index of the optimization is composed of the minimum fuel consumption and the minimum miss distance of the interception. Finally, optimization results of GA and the complex algorithm （CA） are compared. Simulation results show that compared with the traditional opti- mization method, GA can converge to the global optimization better in solving the complex constrained nonlinear combinatorial optimization of the exo-atmospheric interceptor, and reduce the fuel consumption and the miss distance.

Optimal structural design for a certain near-space composite propeller of airship using adaptive region division blending model

Near-space airship is a frontier and hotspot in current military research and development,and the near-space composite propeller is the key technology for its development.In order to obtain higher aerodynamic efficiency at an altitude of 22 km,a certain near-space composite propeller is designed as a long and slender aerodynamic shape with a 10 m diameter,which brings many challenges to the composite structure design.The initial design is obtained by the composite structure variable stiffness design method using based on fixed region division blending model.However,it weighs 23.142 kg,exceeding the required 20 kg.In order to meet the structural design requirements of the propeller,a variable stiffness design method using the adaptive region division blending model is proposed in this paper.Compared with the methods using the fixed region division blending model,this method optimizes region division,stacking thickness and stacking sequence in a single level,considering the coupling effect among them.Through a more refined region division,this method can provide a more optimal design for composite tapered structures.Additionally,to improve the efficiency of optimization subjected to manufacturing constraints,a hierarchical penalty function is proposed to quickly filter out the solutions that do not meet manufacturing constraints.The above methods combined with a Genetic Algorithm(GA)using specific encoding are adopted to optimize the near-space composite propeller.The optimal design of the structure weighs 18.831 kg,with all manufacturing constraints and all structural response constraints being satisfied.Compared with the initial design,the optimal design has a more refined region division,and achieves a weight reduction of 18.6%.This demonstrates that a refined region division can significantly improve the mechanical performance of the composite tapered structure.

基于MADIS的Interceptor技术实现分布系统的数据加密传输

本文结合MADIS的Interceptor技术,探讨了用Delphi开发基于Socket连接的三层分布式应用系统的安全性的问题,并给出了数据加密传输的解决方案。

直升机主动拦截防护系统发展现状及关键技术研究

直升机低空作战时易受各类地空/空空武器的攻击,针对近距发射的RPG和抗干扰能力越来越强的导弹,在传统的红外诱饵弹、激光定向干扰等“软杀伤”手段之外,亟需具备“硬杀伤”能力的主动拦截防护系统。为了研究直升机主动防护系统实现的关键技术,对国外直升机主动拦截系统的发展现状与趋势进行了分析,在此基础上,针对直升机主动拦截防护系统研制过程中所需解决的来袭威胁实时探测告警技术、高精度拦截火力控制技术、精准控制、快速响应的拦截弹药设计技术等关键技术的实现途径进行了分析。

弹载红外探测器对拦截弹的探测能力分析

在弹载平台上加装红外探测器,从而对拦截弹进行探测和预警,是提高弹载平台突防和生存能力的创新性手段。本文针对弹载红外探测器对拦截弹的探测能力,分析了拦截弹的红外辐射特性,并推测了用于探测拦截弹的红外探测器参数。同时,根据探测概率和输入信噪比的关系以及基于辐射差的信噪比模型推导了探测概率模型。在此基础上,分析了对末段、中段防御拦截弹的探测需求,从探测概率、作用距离两个方面对弹载红外探测器的探测能力进行了分析。分析结果表明:弹载红外探测器对末段拦截弹具有较强的探测能力,对于中段拦截弹只有在日照区能够保证探测需求,而在日影区只在一定探测视角下具备探测能力。