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101.
空战中协同干扰、探测、攻击任务分配   总被引:1,自引:0,他引:1  
针对空战中协同干扰任务分配问题,根据己方飞机的干扰功率、干扰工作频段、干扰样式,敌方飞机雷达的工作功率、工作频段、抗干扰样式,建立了干扰功率优势、干扰频率优势、干扰样式优势;再考虑己方飞机的干扰作战能力以及敌我双方的空战能力指数建立了总的干扰优势,建立了协同干扰任务分配模型.根据干扰后敌方飞机的距离性能以及敌我双方的空战态势,对己方飞机对敌方飞机的探测能力、攻击能力进行了研究,建立了多机协同探测加攻击任务分配模型.采用遗传算法对建立的任务模型问题进行优化求解.仿真结果表明,这些模型能够有效地完成协同干扰、探测加攻击任务分配.   相似文献   
102.
基于增强型比例导引律和分布式网络同步理论,设计了一类攻击机动目标的多导弹系统分布式协同制导律。该制导律由各导弹本地制导律和分布式协同导引策略两部分组成:本地制导律为增强型比例导引律,进一步利用代数图论和非线性系统一致性理论,得到基于邻接个体信息交互的分布式协同制导律,实现多导弹对目标的同时协同攻击;该分布式协同制导律仅需视距内各相邻导弹间互相传输各自的状态信息,算法具有较低的通信代价和较好的可扩展性。最后给出了相关数值仿真算例,仿真结果验证了算法的有效性。  相似文献   
103.
In this paper, the finite thrust nonplanar transfer and cooperative rendezvous are investigated. The indirect method is adopted in the optimization process. The energy-optimal to fuel-optimal continuation is performed by using the homotopy method. An initial guess generator (IGG) is designed based on a simplified dynamical model to overcome the difficulty in providing the initial guess. Some reasonable simplifications on the dynamical model are applied based on the near-circular near-coplanar transfer. The initial guess can be obtained by analytically solving a system of linear equations. Therefore, the IGG has high computational efficiency. Moreover, the terminal time and state are estimated by IGG to deal with the cooperative rendezvous problem. Numerical examples are presented and the validity of the “IGG-Homotopy” combined algorithm is verified.  相似文献   
104.
Navigation and proximity to non-cooperative targets have garnered the interest of both academia and industry. This paper proposes a new space operation concept that would enable two CubeSats equipped with only optical sensor to achieve autonomous and robust proximity with uncooperative satellites. This is a novel strategy for distributed spacecraft missions and applications.Because optical sensors are lightweight and therefore reduce reliance on external measurement sources, the case for their use is compelling. Designing robust guidance and control algorithm is the greatest challenge for optical sensors because relative distance information is unavailable, whereas range information is required for safe proximity. The purpose of this paper is to propose a novel concept in which two CubeSats cooperate and share angle measurement data to approach uncooperative targets despite their maneuverability.This paper introduces a new guidance scheme for proximity operations, namely cooperative augmented proportional navigation (CAPN). Modern control law is applied along line-of-sight (LOS) while classical proportional navigation is applied in the normal direction of LOS. By measuring only elevation and azimuth angles between each chaser and the target, the algorithm can account for a maneuvering target. The cooperative scheme offers estimation-based distance measurement, which enhances the observability of angle-only navigation.Target’s maneuverability and different control parameter settings have been considered in simulation scenarios. The degree of observability (DOO) is then introduced as the quantitative observability analysis metric to validate the effectiveness of the guidance scheme and precision of the estimation. The results of simulations have demonstrated that the CAPN proposed in this paper is capable of completing challenging proximity missions.  相似文献   
105.
针对具有非完整约束的多无人机系统编队控制问题,提出了一种基于滑模的协同编队控制算法。控制目标是使多无人机系统能够收敛到期望编队,并且能够跟踪上期望的运动轨迹。在领导-跟随结构中,编队的期望运动轨迹由一个动态的虚拟领导者来表示,仅部分跟随者先验已知虚拟领导者信息,并且所有跟随者之间只能局部交互信息。首先,采用分布式状态观测器,使所有跟随者能够在有限时间内估计出虚拟领导者的状态。然后,利用该观测器的估计状态,提出了基于滑模的协同编队控制算法。最后,基于李雅普诺夫稳定性理论证明了多无人机系统的稳定性,并且通过5架无人机的仿真验证了所提算法的有效性。  相似文献   
106.
《中国航空学报》2022,35(9):293-305
Taxiing aircraft and towed aircraft with drawbar are two typical dispatch modes on the flight deck of aircraft carriers. In this paper, a novel hierarchical solution strategy, named as the Homogenization-Planning-Tracking (HPT) method, to solve cooperative autonomous motion control for heterogeneous carrier dispatch systems is developed. In the homogenization layer, any towed aircraft system involved in the sortie task is abstracted into a virtual taxiing aircraft. This layer transforms the heterogeneous systems into a homogeneous configuration. Then in the planning layer, a centralized optimal control problem is formulated for the homogeneous system. Compared with conducting the path planning directly with the original heterogeneous system, the homogenization layer contributes to reduce the dimension and nonlinearity of the formulated optimal control problem in the planning layer and consequently improves the robustness and efficiency of the solution process. Finally, in the tracking layer, a receding horizon controller is developed to track the reference trajectory obtained in the planning layer. To improve the tracking performance, multi-objective optimization techniques are implemented offline in advance to determine optimal weight parameters used in the tracking layer. Simulations demonstrate that smooth and collision-free cooperative trajectory can be generated efficiently in the planning phase. And robust trajectory tracking can be realized in the presence of external disturbances in the tracking phase. The developed HPT method provides a promising solution to the autonomous deck dispatch for unmanned carrier aircraft in the future.  相似文献   
107.
阳极层推力器(TAL)作为一种高功率、比冲、效率的电推力器逐渐成为国内外研究机构关注的重点,其在深空探测领域具有巨大应用潜力。然而,传统的氙工质不仅价格昂贵、提纯难度大、需要高压贮存,而且不能充分发挥TAL的性能优势。固体金属铋工质具有贮存密度高、成本低、易电离等特点成为代替氙工质的理想选择。本文根据TAL的工作原理与结构特点,对铋工质的适用性进行论述。首先对该推力器的研究现状和发展趋势进行概述;其次对铋工质的性能优势进行了阐述;然后对该推力器的结构组成、工作原理及关键技术进行总结与分析;最后对该推力器的应用前景进行展望。  相似文献   
108.
针对集群编队条件下对高精度时间同步的需求,对通导一体高精度时间同步方法进行了研究,将卫星导航系统与数据链系统进行深度融合,提出了动基座条件下基于卫星导航载波差分算法的节点间高精度时间同步算法。该算法通过协同时间驯服的方式来抑制两次定位间隔间受钟漂影响导致的节点间时间同步误差发散以及节点间时钟修正不同步导致的时间同步误差,提升了编队组网条件下节点间的时间同步精度。最后,通过仿真对算法进行了验证。结果表明,时空同步精度可以达到1ns,可有力支撑未来集群编队作战、高精度协同探测、高精度协同制导等典型场景下对节点间高精度时间同步的需求。  相似文献   
109.
针对多无人机绳索悬挂协同搬运跟踪控制问题,设计了一种新的固定时间协同跟踪控制算法。首先,通过旋量分析,计算系统不同状态下的有效旋量空间,并根据静力学平衡计算系统在有效旋量空间约束下的拉力容许裕度。其次,在保证绳索张紧以及最大拉力约束的条件下,基于微分平坦性以及绳索拉力优化分配算法,规划编队的期望跟踪轨迹。然后,基于Udwadia-Kalaba方程建立系统动力学模型,设计了连续的基于类超扭滑模和积分滑模的鲁棒控制项,以补偿系绳拉力给无人机造成的扰动,并设计了基于双极限齐次性原理的固定时间无人机协同外环位置控制器。针对无人机内环姿态稳定控制,设计了固定时间姿态稳定控制器。仿真结果表明,绳索拉力满足张紧和最大拉力约束,且设计的固定时间协同跟踪控制算法保证了系统在固定时间内稳定跟踪期望轨迹。  相似文献   
110.
针对现代空战多无人机协同多目标任务分配问题,结合标准狼群算法,提出了一种改进狼群算法的多目标任务分配方法。根据狼群的不同分工以及搜索属性,建立了基于自主游走机制的头狼产生规则、基于多策略知识库的探狼游走机制和基于自适应步长的猛狼奔袭及围攻方式,从而对传统狼群算法的随机性进行智能化约束与控制,以解决多无人机协同多目标任务分配问题。数值仿真结果表明,该方法能够快速有效获得任务分配方案,避免陷入局部最优。  相似文献   
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