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Three-dimensional cooperative guidance laws against stationary and maneuvering targets 被引量:36
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作者 Zhao Jiang Zhou Rui Dong Zhuoning 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第4期1104-1120,共17页
This paper presents the cooperative strategies for salvo attack of multiple missiles based on the classical proportional navigation(PN) algorithm.The three-dimensional(3-D) guidance laws are developed in a quite s... This paper presents the cooperative strategies for salvo attack of multiple missiles based on the classical proportional navigation(PN) algorithm.The three-dimensional(3-D) guidance laws are developed in a quite simple formulation that consists of a PN component for target capture and a coordination component for simultaneous arrival.The centralized algorithms come into effect when the global information of time-to-go estimation is obtained, whereas the decentralized algorithms have better performance when each missile can only collect information from neighbors.Numerical simulations demonstrate that the proposed coordination algorithms are feasible to perform the cooperative engagement of multiple missiles against both stationary and maneuvering targets.The effectiveness of the 3-D guidance laws is also discussed. 展开更多
关键词 Coordination algorithms maneuvering target Missile guidance Multiple missiles Three-dimensional (3-D)
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船舶自动避碰方法的研究 被引量:23
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作者 李丽娜 陈聪贵 《中国航海》 CSCD 北大核心 1999年第1期20-24,共5页
本文提出了利用框架式专家系统与数理分析相结合的仿人智能避碰方法,经过计算机仿真表明,实现了海域无约束船舶避碰方案的自动编制。
关键词 避碰 会遇 操纵 专家系统 船舶
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计算机虚拟北航的建造与人机交互的实现 被引量:13
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作者 郝爱民 张蓓 赵沁平 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2000年第4期435-438,共4页
提出了虚拟北航校园场景数据库的层次结构 ,给出了基于碰撞检测的模型控制面场景调度控制方法 ,实现了冗余建模数据删减、纹理映射、多级层次细节模型三种场景复杂度消减策略 ,着重讨论了基于标准二维输入设备的实体选择算法并实现了对... 提出了虚拟北航校园场景数据库的层次结构 ,给出了基于碰撞检测的模型控制面场景调度控制方法 ,实现了冗余建模数据删减、纹理映射、多级层次细节模型三种场景复杂度消减策略 ,着重讨论了基于标准二维输入设备的实体选择算法并实现了对受限运动实体的操纵 ,最后简要介绍了一个通用的。 展开更多
关键词 模型构造 计算机图形学 虚拟现实 人机交互
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波浪中船舶操纵性预报 被引量:7
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作者 沈定安 马向能 +1 位作者 孙芦忠 罗荣彪 《船舶力学》 EI 2000年第4期15-27,共13页
本文通过四自由度操纵运动数学模型 ,对某工程船在静水中和波浪中的Z形运动和回转运动进行预报 ,并由自航模操纵性试验验证。文中还分析了波高 Hw,波长船长比λ/L,船速U和操舵角δ诸因素对该船在波浪中的操纵性的影响。从结果显示可知... 本文通过四自由度操纵运动数学模型 ,对某工程船在静水中和波浪中的Z形运动和回转运动进行预报 ,并由自航模操纵性试验验证。文中还分析了波高 Hw,波长船长比λ/L,船速U和操舵角δ诸因素对该船在波浪中的操纵性的影响。从结果显示可知计算和试验结果是比较吻合的 ,所提供的计算方法适用于船舶静水中和波浪中的操纵性能预报。 展开更多
关键词 波浪 操纵性 工程船 Z形运动 回转运动 试验验证
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Adaptive Integral-type Sliding Mode Control for Spacecraft Attitude Maneuvering Under Actuator Stuck Failures 被引量:15
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作者 HU Qinglei ZHANG Youmin +1 位作者 HUO Xing XIAO Bing 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2011年第1期32-45,共14页
A fault tolerant control (FTC) design technique against actuator stuck faults is investigated using integral-type sliding mode control (ISMC) with application to spacecraft attitude maneuvering control system. The... A fault tolerant control (FTC) design technique against actuator stuck faults is investigated using integral-type sliding mode control (ISMC) with application to spacecraft attitude maneuvering control system. The principle of the proposed FTC scheme is to design an integral-type sliding mode attitude controller using on-line parameter adaptive updating law to compensate for the effects of stuck actuators. This adaptive law also provides both the estimates of the system parameters and external disturbances such that a prior knowledge of the spacecraft inertia or boundedness of disturbances is not required. Moreover, by including the integral feedback term, the designed controller can not only tolerate actuator stuck faults, but also compensate the disturbances with constant components. For the synthesis of controller, the fault time, patterns and values are unknown in advance, as motivated from a practical spacecraft control application. Complete stability and performance analysis are presented and illustrative simulation results of application to a spacecraft show that high precise attitude control with zero steady-error is successfully achieved using various scenarios of stuck failures in actuators. 展开更多
关键词 integral sliding mode control attitude maneuvering stuck failure adaptive control SPACECRAFT
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跟踪机动再入飞行器的交互多模型Unscented卡尔曼滤波方法 被引量:15
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作者 张树春 胡广大 《自动化学报》 EI CSCD 北大核心 2007年第11期1220-1225,共6页
对于目标发生机动时的再入飞行器的跟踪问题,传统跟踪方法是采用机动模型的扩展卡尔曼滤波.本文在提高机动目标跟踪精度的探索中做了两方面的努力,一是在描述目标运动模型方面采用了更符合机动目标运动特性的多模型方法;另一方面,采用... 对于目标发生机动时的再入飞行器的跟踪问题,传统跟踪方法是采用机动模型的扩展卡尔曼滤波.本文在提高机动目标跟踪精度的探索中做了两方面的努力,一是在描述目标运动模型方面采用了更符合机动目标运动特性的多模型方法;另一方面,采用了隐含高阶精度的Unscented卡尔曼匹配滤波方法.对于交互多模型Unscented卡尔曼滤波器在仿真中易出现数值问题,给出了基于平方根滤波的数值鲁棒性的解决方法. 展开更多
关键词 再入目标 机动 Unscented变换 平方根滤波
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Adaptive Maneuvering Frequency Method of Current Statistical Model 被引量:13
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作者 Wei Sun Yongjian Yang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第1期154-160,共7页
Current statistical model(CSM) has a good performance in maneuvering target tracking. However, the fixed maneuvering frequency will deteriorate the tracking results, such as a serious dynamic delay, a slowly convergin... Current statistical model(CSM) has a good performance in maneuvering target tracking. However, the fixed maneuvering frequency will deteriorate the tracking results, such as a serious dynamic delay, a slowly converging speedy and a limited precision when using Kalman filter(KF) algorithm. In this study, a new current statistical model and a new Kalman filter are proposed to improve the performance of maneuvering target tracking. The new model which employs innovation dominated subjection function to adaptively adjust maneuvering frequency has a better performance in step maneuvering target tracking, while a fluctuant phenomenon appears. As far as this problem is concerned, a new adaptive fading Kalman filter is proposed as well. In the new Kalman filter, the prediction values are amended in time by setting judgment and amendment rules,so that tracking precision and fluctuant phenomenon of the new current statistical model are improved. The results of simulation indicate the effectiveness of the new algorithm and the practical guiding significance. 展开更多
关键词 Current statistical model(CSM) maneuvering target tracking adaptive fading Kalman filter(AFKF)
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CFD Investigations of Ship Maneuvering in Waves Using naoe-FOAM-SJTU Solver 被引量:13
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作者 Jianhua Wang Decheng Wan 《Journal of Marine Science and Application》 CSCD 2018年第3期443-458,共16页
Ship maneuvering in waves includes the performance of ship resistance, seakeeping, propulsion, and maneuverability. It is a complex hydrodynamic problem with the interaction of many factors. With the purpose of direct... Ship maneuvering in waves includes the performance of ship resistance, seakeeping, propulsion, and maneuverability. It is a complex hydrodynamic problem with the interaction of many factors. With the purpose of directly predicting the behavior of ship maneuvering in waves, a CFD solver named naoe-FOAM-SJTU is developed by the Computational Marine Hydrodynamics Lab(CMHL) in Shanghai Jiao Tong University. The solver is based on open source platform OpenFOAM and has introduced dynamic overset grid technology to handle complex ship hull-propeller-rudder motion system. Maneuvering control module based on feedback control mechanism is also developed to accurately simulate corresponding motion behavior of free running ship maneuver. Inlet boundary wavemaker and relaxation zone technique is used to generate desired waves. Based on the developed modules, unsteady Reynolds-averaged Navier-Stokes(RANS) computations are carried out for several validation cases of free running ship maneuver in waves including zigzag, turning circle, and course keeping maneuvers. The simulation results are compared with available benchmark data. Ship motions, trajectories, and other maneuvering parameters are consistent with available experimental data, which indicate that the present solver can be suitable and reliable in predicting the performance of ship maneuvering in waves. Flow visualizations, such as free surface elevation, wake flow, vortical structures, are presented to explain the hydrodynamic performance of ship maneuvering in waves. Large flow separation can be observed around propellers and rudders. It is concluded that RANS approach is not accurate enough for predicting ship maneuvering in waves with large flow separations and detached eddy simulation(DES) or large eddy simulation(LES) computations are required to improve the prediction accuracy. 展开更多
关键词 maneuvering in waves Overset grid method Hull-propeller-rudder interaction OPENFOAM naoe-FOAM-SJTU
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野外机动应用的车载CT方舱研究 被引量:15
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作者 晁勇 帅万钧 +7 位作者 李安民 王福利 张少东 谭树林 苏卫华 武超 牛福 段德光 《中国医疗设备》 2014年第4期27-29,115,共4页
目的提高我国灾害医疗救援能力,研究一种可机动应用于野外环境的CT装置。方法将传统CT装置改装后安装于方舱内,通过汽车自装卸方式实现机动运输,采取有效措施保证CT应用条件。结果研制完成的车载CT方舱样机经测试性能良好,能满足野外机... 目的提高我国灾害医疗救援能力,研究一种可机动应用于野外环境的CT装置。方法将传统CT装置改装后安装于方舱内,通过汽车自装卸方式实现机动运输,采取有效措施保证CT应用条件。结果研制完成的车载CT方舱样机经测试性能良好,能满足野外机动应用要求。结论车载CT方舱具有平战适用的特点。 展开更多
关键词 CT机 CT方舱 车载 机动运输 野外环境
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港作拖轮在大型船舶港内操纵中的使用 被引量:14
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作者 鲍文明 《中国航海》 CSCD 北大核心 2006年第3期23-26,共4页
结合自身参加大型船舶引航作业的实践与体会,从理论上阐述了港作拖轮顶推位置不同时对大船运动与操纵的影响。同时就港作拖轮在作业中产生的几种临界现象和在协助大型船舶靠、离泊作业中的特例及其相应的操作方法作了说明。
关键词 水路运输 港作拖轮 操纵 离泊 顶推
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An impact angle constraint integral sliding mode guidance law for maneuvering targets interception 被引量:11
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作者 ZHANG Wenjie FU Shengnan +1 位作者 LI Wei XIA Qunli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第1期168-184,共17页
An integral sliding mode guidance law(ISMGL)combined with the advantages of the integral sliding mode control(SMC)method is designed to address maneuvering target interception problems with impact angle constraints.Th... An integral sliding mode guidance law(ISMGL)combined with the advantages of the integral sliding mode control(SMC)method is designed to address maneuvering target interception problems with impact angle constraints.The relative motion equation of the missile and the target considering the impact angle constraint is established in the longitudinal plane,and an integral sliding mode surface is constructed.The proposed guidance law resolves the existence of a steady-state error problem in the traditional SMC.Such a guidance law ensures that the missile hits the target with an ideal impact angle in finite time and the missile is kept highly robust throughout the interception process.By adopting the dynamic surface control method,the ISMGL is designed considering the impact angle constraints and the autopilot dynamic characteristics.According to the Lyapunov stability theorem,all states of the closed-loop system are finally proven to be uniformly bounded.Simulation results are compared with the general sliding mode guidance law and the trajectory shaping guidance law,and the findings verify the effectiveness and superiority of the ISMGL. 展开更多
关键词 impact angle constraint integral sliding mode maneuvering target Lyapunov stability dynamic characteristic
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An adaptive attitude algorithm based on a current statistical model for maneuvering acceleration 被引量:11
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作者 Wang Menglong Wang Hua 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第1期426-433,共8页
A current statistical model for maneuvering acceleration using an adaptive extended Kalman filter(CS-MAEKF) algorithm is proposed to solve problems existing in conventional extended Kalman filters such as large esti... A current statistical model for maneuvering acceleration using an adaptive extended Kalman filter(CS-MAEKF) algorithm is proposed to solve problems existing in conventional extended Kalman filters such as large estimation error and divergent tendencies in the presence of continuous maneuvering acceleration. A membership function is introduced in this algorithm to adaptively modify the upper and lower limits of loitering vehicles' maneuvering acceleration and for realtime adjustment of maneuvering acceleration variance. This allows the algorithm to have superior static and dynamic performance for loitering vehicles undergoing different maneuvers. Digital simulations and dynamic flight testing show that the yaw angle accuracy of the algorithm is 30% better than conventional algorithms, and pitch and roll angle calculation precision is improved by 60%.The mean square deviation of heading and attitude angle error during dynamic flight is less than3.05°. Experimental results show that CS-MAEKF meets the application requirements of miniature loitering vehicles. 展开更多
关键词 Attitude and heading reference system Current statistical model Kalman filter Loitering vehicle maneuvering acceleration Membership function
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Modeling of Ship Maneuvering Motion Using Neural Networks 被引量:13
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作者 Weilin Luo Zhicheng Zhang 《Journal of Marine Science and Application》 CSCD 2016年第4期426-432,共7页
In this paper, Neural Networks (NNs) are used in the modeling of ship maneuvering motion. A nonlinear response model and a linear hydrodynamic model of ship maneuvering motion are also investigated. The maneuverabil... In this paper, Neural Networks (NNs) are used in the modeling of ship maneuvering motion. A nonlinear response model and a linear hydrodynamic model of ship maneuvering motion are also investigated. The maneuverability indices and linear non-dimensional hydrodynamic derivatives in the models are identified by using two-layer feed forward NNs. The stability of parametric estimation is confirmed. Then, the ship maneuvering motion is predicted based on the obtained models. A comparison between the predicted results and the model test results demonstrates the validity of the proposed modeling method. 展开更多
关键词 ship maneuvering response models mathematical modeling group model system identification neural networks
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Three-dimensional cooperative guidance strategy and guidance law for intercepting highly maneuvering target 被引量:12
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作者 Ziyan CHEN Jianglong YU +1 位作者 Xiwang DONG Zhang REN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第5期485-495,共11页
Cooperative interception of the target with strong maneuverability by multiple missiles with weak maneuverability in the three-dimensional nonlinear model is studied.Firstly,the three-dimensional nonlinear model of co... Cooperative interception of the target with strong maneuverability by multiple missiles with weak maneuverability in the three-dimensional nonlinear model is studied.Firstly,the three-dimensional nonlinear model of cooperative guidance is established.The three-dimensional reachable region is represented composed of lateral acceleration and longitudinal acceleration in the two-dimensional coordinate system.Secondly,the problem of the multiple missile’s reachable coverage area is transformed into the problem of cooperative coverage.A cooperative coverage strategy is proposed and an algorithm for quickly calculating the number of required missiles is designed.Then,the guidance law based on the cooperative coverage strategy is proposed,and it is proved that cooperative interception of the target can be achieved under the acceleration limit.Moreover,the relations among the number of missiles,the initial array position of terminal guidance and the coverage area of the target’s large maneuver are analyzed.The dynamic adjustment strategy of guidance parameters is proposed to reduce the guidance error.Finally,simulation results show that multiple missiles with low maneuverability can achieve effective interception of target with strong maneuverability through the proposed cooperative strategy and cooperative guidance method. 展开更多
关键词 Acceleration constraint Cooperative interception Coverage strategy Guidance law Highly maneuvering target
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Modified unscented Kalman filter using modified filter gain and variance scale factor for highly maneuvering target tracking 被引量:9
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作者 Changyun Liu Penglang Shui +1 位作者 Gang Wei Song Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第3期380-385,共6页
To improve the low tracking precision caused by lagged filter gain or imprecise state noise when the target highly maneuvers, a modified unscented Kalman filter algorithm based on the improved filter gain and adaptive... To improve the low tracking precision caused by lagged filter gain or imprecise state noise when the target highly maneuvers, a modified unscented Kalman filter algorithm based on the improved filter gain and adaptive scale factor of state noise is presented. In every filter process, the estimated scale factor is used to update the state noise covariance Qk, and the improved filter gain is obtained in the filter process of unscented Kalman filter (UKF) via predicted variance Pk|k-1, which is similar to the standard Kalman filter. Simulation results show that the proposed algorithm provides better accuracy and ability to adapt to the highly maneuvering target compared with the standard UKF. 展开更多
关键词 unscented Kalman filter (UKF) target tracking filter gain maneuvering target NONLINEARITY modified unscented Kalman filter (MUKF).
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An improved multiple model GM-PHD filter for maneuvering target tracking 被引量:9
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作者 Wang Xiao Han Chongzhao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第1期179-185,共7页
In this paper, an improved implementation of multiple model Gaussian mixture probability hypothesis density (MM-GM-PHD) filter is proposed. For maneuvering target tracking, based on joint distribution, the existing ... In this paper, an improved implementation of multiple model Gaussian mixture probability hypothesis density (MM-GM-PHD) filter is proposed. For maneuvering target tracking, based on joint distribution, the existing MM-GM-PHD filter is relatively complex. To simplify the filter, model conditioned distribution and model probability are used in the improved MM-GM-PHD filter. In the algorithm, every Gaussian components describing existing, birth and spawned targets are estimated by multiple model method. The final results of the Gaussian components are the fusion of multiple model estimations. The algorithm does not need to compute the joint PHD distribution and has a simpler computation procedure. Compared with single model GM-PHD, the algorithm gives more accurate estimation on the number and state of the targets. Compared with the existing MM-GM-PHD algorithm, it saves computation time by more than 30%. Moreover, it also outperforms the interacting multiple model joint probabilistic data association (IMMJPDA) filter in a relatively dense clutter environment. 展开更多
关键词 ESTIMATION Gaussian mixture maneuvering target racking Multiple model Probability hypothesis density
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Target Tracking Using the Interactive Multiple Model Method 被引量:6
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作者 张劲松 杨位钦 胡士强 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期299-304,共6页
Aim To develop a practical target tracking algorithm for different motion modes. Methods After creation of the new model, it was implemented by computer simulation to prove its performance and compared with the of... Aim To develop a practical target tracking algorithm for different motion modes. Methods After creation of the new model, it was implemented by computer simulation to prove its performance and compared with the often-used current statistical model. Results The simulation results show that the new IMM (interactive multiple model) have low tracking error in both maneuVering segment and non^Inaneuwi segment while the current statistical model bas muCh higher tracking error in non-maneuvering segment. Conclusion In the point of trackintaccuracy, the new IMM method is much better than the current acceleration method. It can develop into a practical target hacking method. 展开更多
关键词 interactive multiple model TRACKING maneuvering target Kalman filter
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Analysis of 1/2 sub-harmonic resonance in a maneuvering rotor system 被引量:11
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作者 HOU Lei CHEN YuShu 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第1期203-209,共7页
This paper focuses on the 1/2 sub-harmonic resonance of an aircraft’s rotor system under hovering flight that can be modeled as a maneuver load G in the equations of motion.The effect on the rotor system is analyzed ... This paper focuses on the 1/2 sub-harmonic resonance of an aircraft’s rotor system under hovering flight that can be modeled as a maneuver load G in the equations of motion.The effect on the rotor system is analyzed by using theoretical methods.It is shown that the sub-harmonic resonance may occur due to maneuvering flight conditions.The larger the eccentricity E and the maneuver load G,the greater the sub-harmonic resonance.The effects of nonlinear stiffness,damping of the system,maneuver load,and eccentricity on the sub-harmonic resonance region in parameter planes are also investigated.Bifurcation diagrams of the analytical solutions are in good agreement with that of the numerical simulation solutions.These results will contribute to the understanding of the nonlinear dynamic behaviors of maneuvering rotor systems. 展开更多
关键词 sub-harmonic resonance maneuvering rotor system hovering flight maneuver load
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高超末段机动突防/精确打击弹道建模与优化 被引量:11
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作者 李静琳 陈万春 闵昌万 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2018年第3期556-567,共12页
针对高超声速飞行器再入末段机动突防、精确打击问题,从最优控制角度出发,提出了一种考虑拦截弹动力学特性的最优机动突防弹道优化方法,获得了高超声速飞行器的最大机动能力。该方法将拦截弹运动模型引入突防弹道优化的模型中,通过施加... 针对高超声速飞行器再入末段机动突防、精确打击问题,从最优控制角度出发,提出了一种考虑拦截弹动力学特性的最优机动突防弹道优化方法,获得了高超声速飞行器的最大机动能力。该方法将拦截弹运动模型引入突防弹道优化的模型中,通过施加约束限制拦截弹按照比例导引律飞行。根据飞行任务和交战双方的弹道特点分段,结合各段的任务和特性,分别提出了突防性能指标和精确打击性能指标等,并通过加权函数将各个独立、矛盾的性能指标统一,建立了多对象、多段、多约束机动突防弹道优化模型,采用Radau多段伪谱法(MRPM)进行求解。针对该问题求解的初值敏感、可行域窄等问题,提出了一系列弹道优化策略,提高了收敛速度和求解精度,最终获得了最优机动弹道,并通过协态映射原理对其最优性进行了验证。结果表明,该方法能充分发挥高超声速飞行器的机动能力,获得满足落点精度要求的突防弹道,相对已有方法,将脱靶量提高了1~2个量级。灵敏度分析表明,该弹道对拦截弹的发射时间不敏感。 展开更多
关键词 机动 突防 拦截 优化策略 最优性条件 灵敏度分析
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Modified joint probabilistic data association with classification-aided for multitarget tracking 被引量:8
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作者 Ba Hongxin Cao Lei +1 位作者 He Xinyi Cheng Qun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期434-439,共6页
Joint probabilistic data association is an effective method for tracking multiple targets in clutter, but only the target kinematic information is used in measure-to-track association. If the kinematic likelihoods are... Joint probabilistic data association is an effective method for tracking multiple targets in clutter, but only the target kinematic information is used in measure-to-track association. If the kinematic likelihoods are similar for different closely spaced targets, there is ambiguity in using the kinematic information alone; the correct association probability will decrease in conventional joint probabilistic data association algorithm and track coalescence will occur easily. A modified algorithm of joint probabilistic data association with classification-aided is presented, which avoids track coalescence when tracking multiple neighboring targets. Firstly, an identification matrix is defined, which is used to simplify validation matrix to decrease computational complexity. Then, target class information is integrated into the data association process. Performance comparisons with and without the use of class information in JPDA are presented on multiple closely spaced maneuvering targets tracking problem. Simulation results quantify the benefits of classification-aided JPDA for improved multiple targets tracking, especially in the presence of association uncertainty in the kinematic measurement and target maneuvering. Simulation results indicate that the algorithm is valid. 展开更多
关键词 multi-target tracking data association joint probabilistic data association classification information track coalescence maneuvering target.
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