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1.
为提高弹道导弹在拦截末段机动突防性能,基于微分对策理论对三维空间中的机动突防制导律进行研究。从视线倾角和视线偏角的变化率模型出发建立拦截-突防双方的运动模型;推导了双方在拦截末段的最优制导律;在Simulink下搭建仿真平台,并选取不同参数组合进行多次仿真。仿真结果表明,本文提出的突防制导律可使脱靶量达到12m,突防效果明显。 相似文献
2.
规划、规范和规则是建设项目审批依据的三个基本来源,三者共同构成开发控制管理制度的三大核心体系。研究结合深圳实践,阐述三大体系的特征、构成和分类,分析三者在静态条件下的优先关系和在动态条件下的互动关系,尝试揭示三大体系之间相互替代、补充、促进、转化和融合的演化规律。 相似文献
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4.
引信与导引头一体化( GIF)设计是提高引战配合效率的有效途径.结合一般雷达导引头,首先介绍一种波控引信与硬件一体化引信进行设计,提出一体化引信起爆控制的逻辑算法流程;然后建立基于GIF信息条件下和基于引信自身信息条件下的两种弹目交会模型,并推导了最佳起爆角、起爆延时的数学表达式;最后分析计算几种弹目交会条件下,多普勒... 相似文献
5.
For the terminal phase guidance problem of the missile intercepting weaving maneuvering target, an adaptive internal model guidance laws in the three-dimensional (3-D) engagement space is proposed in this paper. The guidance law adopts the disturbance rejection theory by treating the target weaving maneuvering accelerations as external disturbance, which comprises of nominal part and adaptive part. The nominal part based on feedback linearization method ensures the whole guidance system stable and the adaptive part based on internal model principle is used to recover the disturbance signals on-line to reject the target maneuver asymptotically. The algorithm guarantees the whole guidance system with satisfying performance both in transient and steady state on the effect of target maneuver on guidance system. The stability analyses and theory proof are provided in this paper. At last, numerical simulations are carried out to illustrate the effectiveness of the proposed guidance law. 相似文献
6.
基于模糊逻辑的导弹扩展比例导引律 总被引:1,自引:0,他引:1
临近空间高超声速大机动目标的拦截制导律一直是现代制导与控制方面的一个难点和热点。运用模糊逻辑的方法,改进了扩展比例导引律,使导弹在拦截过程中能够有效跟踪导弹至目标视线转率的变化及目标的机动加速度,拦截末段视线转率收敛,实施成功拦截。 相似文献
7.
The paper describes the development of the Navigation, Guidance and Control system of a small, prototypal Autonomous Surface Vehicle (ASV), which is part of an ASV/UUV (Unmanned Underwater Vehicle) robotic system. The main task of the ASV is to serve as supply vessel for the UUV it can carry, deploy and recover and to allow communication with a remote control station. The main problem the NGC system has to handle is that of making the ASV track the UUV and maintain the relative distance within a given bound, using delayed information about the UUV position provided by an acoustic tracking and positioning systems. The specific tracking problem is formulated in a suitable way and a strategy for its solution is proposed and implemented by means of an appropriate control architecture. Stability is discussed using Lyapunov techniques and performances are shown by means of simulations. 相似文献
8.
This paper describes the design of a guidance law used for guiding a hypersonic gliding vehicle against a ground target from a near-vertical orientation with a specified final speed and a near-zero final load factor. The guidance law consists of two terms: one is Trajectory-Shaping Guidance (TSG) used for steering the vehicle to the target from the specified orientation; the other is Final-Speed-Control Scheme (FSCS) used for controlling the vehicle to perform lateral maneuver to adjust the final speed. Further, the generalized closed form solutions of TSG are obtained from a more general linearized engagement model, where the speed of the vehicle can be an arbitrary positive function of time. By analyzing these solutions, the stability domain of the guidance coefficients is obtained such that the final load factor is zero. This domain is not affected by the change rate of the speed. Thus, according to this analysis, the proposed guidance law can achieve a near zero final load factor by properly selecting the guidance coefficients in the stability domain. 相似文献
9.
Graphics processing unit (GPU) has been applied successfully in many computation and memory intensive realms due to its superior performances in float-pointing calculation, memory bandwidth and power consumption, and has great potential in power system applications. Contingency screening is a major time consuming part of contingency analysis. In the absence of relevant existing research, this paper is the first of its kind to propose a novel GPU-accelerated algorithm for direct current (DC) contingency screening. Adapting actively unique characteristics of GPU software and hardware, the proposed GPU algorithm is optimized from four aspects: data transmission, parallel task allocation, memory access, and CUDA (Compute Unified Device Architecture) stream. Case studies on a 3012-bus system and 8503-bus system have shown that the GPU-accelerated algorithm, in compared with its counterpart CPU implementation, can achieve about 20 and 50 times speedup respectively. This highly promising performance has demonstrated that carefully designed performance tuning in conjunction with GPU programing architecture is imperative for a GPU-accelerated algorithm. The presented performance tuning strategies can be applicable to other GPU applications in power systems. 相似文献
10.
To concretely provide a feasible solution for homing missiles with the precise impact time and angle, this paper develops a novel guidance law, based on the nonlinear engagement dynamics. The guidance law is firstly designed with the prior assumption of a stationary target, followed by the practical extension to a moving target scenario. The time-varying sliding mode (TVSM) technique is applied to fulfill the terminal constraints, in which a specific TVSM surface is constructed with two unknown coefficients. One is tuned to meet the impact time requirement and the other one is targeted with a global sliding mode, so that the impact angle constraint as well as the zero miss distance can be satisfied. Because the proposed law possesses three guidance gain as design parameters, the intercept trajectory can be shaped according to the operational conditions and missile׳s capability.To improve the tolerance of initial heading errors and broaden the application, a new frame of reference is also introduced. Furthermore, the analytical solutions of the flight trajectory, heading angle and acceleration command can be totally expressed for the prediction and offline parameter selection by solving a first-order linear differential equation. Numerical simulation results for various scenarios validate the effectiveness of the proposed guidance law and demonstrate the accuracy of the analytic solutions. 相似文献