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基于agent的作战建模与仿真是无人机集群侦察效能评估的重要方法,但以往方法中agent行为机制 和模型结构难以描述复杂任务场景下的自组织侦察行为。以反海盗侦察任务为例,提出一种面向集群自组织 侦察的作战建模与仿真方法。设计多agent分层复合行为机制和可组合模块化agent模型结构,通过简单行为 的组合描述复杂行为;通过信息素图模块与航路管理模块的交互,实现自组织航路规划与飞行控制;并通过仿 真算例,来验证方法的可行性,对比分析不同航路规划方法的侦察效能。结果表明:自组织航路规划对中断航 路侦察的动态事件的适应性更强;对于大区域、长时间、低目标密度的区域覆盖侦察任务,仅通过改进航路规划 方法来降低访问间隔难以显著提高目标发现概率。 相似文献
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为了寻找满足某些约束的最隐蔽安全的航路,基于遗传算法提出了一种适用于倾斜发射反舰导弹的航路规划算法。首先,分析了倾斜发射反舰导弹的飞行特征,提出了一种航路编码方法;其次,根据该航路编码方法的特点设计了相应的遗传操作;最后,通过仿真试验验证了该算法的有效性。 相似文献
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针对大量固定翼无人机在有限空域内的协同避碰问题,提出了一种基于多智能体深度强化学习的计算制导方法。首先,将避碰制导过程抽象为序列决策问题,通过马尔可夫博弈理论对其进行数学描述。然后提出了一种基于深度神经网络技术的自主避碰制导决策方法,该网络使用改进的Actor-Critic模型进行训练,设计了实现该方法的机器学习架构,并给出了相关神经网络结构和机间协调机制。最后建立了一个实体数量可变的飞行场景模拟器,在其中进行"集中训练"和"分布执行"。为了验证算法的性能,在高航路密度场景中进行了仿真实验。仿真结果表明,提出的在线计算制导方法能够有效地降低多无人机在飞行过程中的碰撞概率,且对高航路密度场景具有很好的适应性。 相似文献
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动态环境下飞行器在线航迹规划问题的难点在于规划方法需要适应飞行环境的动态变化,以及规划快速性与准确性之间的矛盾。在综合分析动态环境下航迹规划问题特点的基础上,提出了一种在线航迹规划的滚动优化方法。采用模型预测控制对指令航迹进行滚动优化。通过引入新的末端惩罚项,构建了一种更能反映未来段航迹偏离程度的性能指标,使飞行器能够对未来段参考航迹的航向变化提前作出反应。相比传统的固定时域的规划方法,规划的快速性和准确性同时得到了提高。仿真结果表明,该方法能够在动态环境下在线生成较精确的指令航迹,引导飞行器以较小的偏差沿参考航迹飞行。 相似文献
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无人机航路规划技术研究进展 总被引:1,自引:0,他引:1
无人机航路规划问题本质是多约束条件下,多目标函数求极值的优化问题.规划出满足任务要求、导航、安全性等约束的较优航路,对提高无人机的武器系统性能有重要意义.通过对无人机航路规划的研究,对无人机航路规划问题进行了概括和总结,阐述了无人机航路规划的框架结构以及静态全局规划和动态局部规划方法的研究现状.分析了近年来常用的几种规划算法,着重分析了启发式算法以及遗传算法.在此基础上,对今后的研究方向进行了展望. 相似文献
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为了使航路规划算法在三维动态环境下能够快速规划出较优可行航路,基于快速扩展随机树算法(RRT),对规划航路点进行了无人机飞行动力学约束,并且设计了局部航路动态优化策略。针对传统的航路跟踪控制律跟踪较为曲折的航线时跟踪误差较大的问题,通过将规划算法得出的姿态指令引入姿态控制回路的方式,提高了航路跟踪控制算法的快速性与准确性。在此基础上,搭建了无人机验证平台,利用该验证平台完成了无人机自主避障飞行试验,对算法的有效性进行了验证,并对算法性能进行了评估。 相似文献
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NING Guo-dong ZHANG Shu-guang FANG Zhen-ping 《中国航空学报》2007,20(1):1-8
A method for the implementation of integrated three-degree-of-freedom constrained entry guidance for reusable launch vehicle is presented. Given any feasible entry conditions, terminal area energy management interface conditions, and the reference trajectory generated onboard then, the method can generate a longitudinal guidance profile rapidly, featuring linear quadratic regular method and a proportional-integral-derivative tracking law with time-varying gains, which satisfies all the entry corridor constraints and meets the requirements with high precision. Afterwards, by utilizing special features of crossrange parameter, establishing bank-reversal corridor, and determining bank-reversals according to dynamically adjusted method, the algorithm enables the lateral entry guidance system to fly a wide range of missions and provides reliable and good performance in the presence of significant aerodynamic modeling uncertainty. Fast trajectory guidance profiles and simulations with a reusable launch vehicle model for various missions and aerodynamic uncertain-ties are presented to demonstrate the capacity and reliability of this method. 相似文献
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基于飞机油箱模型形状特征油量测量切片步长选择方法研究 总被引:1,自引:0,他引:1
在分析飞机数字式油量测量过程中目前广泛使用的切片法油量测量原理的基础上,针对现有的定步长切片法无法得到准确、可靠的燃油质量特性数据库的缺陷,结合对飞机油箱模型形状特征的分析,提出了基于飞机油箱模型形状特征的油量测量切片步长选择方法。此方法包括切片步长整体和局部选择两个过程,整体选择以实现相邻两切片平面所夹油箱模型体积近似相等为目的来确定切片步长,以体现油箱模型截面整体变化规律;局部选择以设计切片平面与截面突变平面重合或尽可能接近的方式,突出油箱截面的局部变化特征。实验结果表明:该切片步长选择方法较定步长方法能够建立更为合理、可靠的燃油质量特性数据库,从而提高了油量测量精度。 相似文献
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The effect of inlet conditions on the flow and heat transfer in multiple rotating cavity with axial throughflow 总被引:1,自引:0,他引:1
This paper discusses experimental results from two different build configurations of a heated multiple rotating cavity test rig.Measurements of heat transfer from the discs and tangential velocities are presented.The test rig is a 70% full scale version of a high pressure compressor stack of an axial gas turbine engine.Of particular interest are the internal cylindrical cavities formed by adjacent discs and the interaction of these with a central axial throughflow of cooling air.Tests were carried out for a range of non-dimensional parameters representative of high pressure compressor internal air system flows(Re up to 5×106 and Rez up to 2×105).Two different builds have been tested.The most significant difference between these two build configurations is the size of the annular gap between the(non-rotating) drive shaft and the bores of the discs.The heat transfer data were obtained from thermocouple measurements of surface temperature and a conduction solution method.The velocity measurements were made using a two component,LDA system.The heat transfer results from the discs show differences between the two builds.This is attributed to the wider annular gap allowing more of the throughflow to penetrate into the cavity.There are also significant differences between the radial distributions of tangential velocity in the two builds of the test rig.For the narrow annular gap,there is an increase of non-dimensional tangential velocity V/Ωr with radial location to solid body rotation V/Ωr=1.For the wider annular gap,the non-dimensional velocities show a decrease with radial location to solid body rotation. 相似文献
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Abnormal Shape Mould Winding 总被引:1,自引:0,他引:1
Fu Hongya Wang Xianfeng Han Zhenyu Fu Yunzhong 《中国航空学报》2007,20(6):552-558
为解决网格化芯模的缠绕问题,本文提出了复合材料面片缠绕机理;接着详细分析了面片缠绕过程中的芯模凹曲面上纤维滑线和架空现象,应用微分几何曲面理论和空间几何理论,提出判据及其解决方案;最后,针对飞机发动机进气道的缠绕成型,编制缠绕控制程序并进行相应的实验,验证了面片缠绕方法的可行性。 相似文献
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FU Hong-jun MA Chong-qi KUANG Nai-hang LUAN Shi-lin 《中国航空学报》2007,20(2):124-128
This work was dedicated to performing surface oxidation and coating treatments on carbon fibers (CF) and investigating the changes of fiber surface properties after these treatments, including surface composition, relative volume of functional groups, and sur- face topography with X-ray photoelectron spectroscopy (XPS) and atom force microscopy (AFM) technology. The results show that, after oxidation treatments, interfacial properties between CF and non-polar polyarylacetylene (PAA) resin are remarkably modified by removing weak surface layers and increasing fiber surface roughness. Coating treatment by high char phenolic resin solution after oxida- tion makes interface of CF/PAA composites to be upgraded and the interfacial properties further bettered. 相似文献
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Xu Chenghai Meng Songhe Zhang Mingfu Zuo Hongbo Wang Guigen 《中国航空学报》2007,20(5):475-480
本文利用有限元法对冷心放肩微量提拉法(SAPMAC)生长大尺寸蓝宝石单晶过程中的热应力进行了模拟计算,应用临界缺陷理论解释了裂纹的萌生与扩展机理。研究表明,晶体内的热应力主要与晶体生长速率,环境温度和结晶取向有关;较大热应力多出现在结晶界面,放肩、收尾以及直径急剧变化等位置;最大热应力总是出现在籽晶与新生晶体的界面附近。裂纹将在临界缺陷位置产生,并在应力作用下沿a或m面扩展。计算结果与实验结果基本吻合,通过晶体生长系统和生长工艺的改进,对晶体的开裂问题得到了有效的抑制。 相似文献
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CHENG Wen-yuan CHANG Yan CUI De-gang XIE Xiang-hui 《中国航空学报》2007,20(1):55-59
To solve the topology optimization of complicated multi-objective continuous/discrete design variables in aircmit structure design, a Parallel Pareto Genetic Algorithm (PPGA) is presented based on grid platform in this paper. In the algorithm, the commercial finite element analysis (FEA) software is integrated as the calculating tool for analyzing the objective functions and the filter of Pareto solution set based on weight information is introduced to deal with the relationships among all objectives. Grid technology is utilized in PPGA to realize the distributed computations and the user interface is developed to realize the job submission and job management locally/remotely. Taking the aero-elastic tailoring of a composite wing for optimization as an example, a set of Pareto solutions are obtained for the decision-maker. The numerical results show that the aileron reversal problem can be solved by adding the limited skin weight in this system. The algorithm can be used to solve complicated topology optimization for composite structures in engineering and the computation efficiency can be improved greatly by using the grid platform that aggregates numerous idle resources. 相似文献