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通过对某型无人靶机的飞行特性进行分析,研究靶机自主导航设计原理,对该型靶机的飞行航路和自主导航装订航线进行规划设计;结合多次供靶实际,研究分析该型靶机空中易出现的特殊情况,并提出可行的处置措施。 相似文献
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设计了一种陶瓷基底的右旋圆极化微带天线,能够满足高温环境下卫星导航系统的应用.天线设计特点有以下四点:天线外形具有低轮廓特性, 适合高速运动飞行器表面的贴装; 采用钛合金材料和高温陶瓷材料, 能够在400 ℃高温环境下正常工作, 具有优异的耐热性能; 加工装配流程均无焊接工艺, 确保天线组件的电连接在高温冲击下的可靠性; 采用中心短路销钉设计, 减少同轴馈针的感抗, 获得优异的阻抗匹配特性.通过仿真优化和实际测试, 验证了该天线性能优异, 满足高温环境下的卫星导航系统的使用要求. 相似文献
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Personalised routing for wheelchair navigation 总被引:1,自引:0,他引:1
《Journal of Location Based Services》2013,7(1):24-54
Wheelchair users are confronted with many outdoor obstacles in everyday travel that can make the task arduous and unsafe, especially in unfamiliar environments. However, if wheelchair users are provided with routes that can safely, accurately and efficiently guide them to their destinations, then the difficulty and danger associated with traveling might be significantly reduced. In this article, we present a routing method suitable for wheelchair users by taking into account sidewalk obstacles such as slope, steps, sidewalk condition and sidewalk traffic as are preferred by users. Our method calculates impedance scores for each sidewalk segment, which are then used to determine an optimal route between any given pair of origin-destination addresses in a sidewalk network. We first discuss sidewalk network parameters and a spatial database suitable for wheelchair navigation. Then we discuss our personalised routing approach. We also describe three methods to weight the impedance level of each sidewalk segment and compare the effectiveness of each method through experimentation using the sidewalk network for the University of Pittsburgh campus area. 相似文献
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比例导引规律相比于直接追踪法,跟踪精度有所提高,但是在目标机动性加大的情况下,传统比例导引规律制导精度仍不理想.因此,给出了三维空间导弹-目标追逃运动的空间矢量方程,建立了三维空间导弹-目标追逃运动模型,并基于李雅普诺夫稳定性理论,设计增广比例导引律(APNG).即在比例制导规律基础上,引入目标加速度补偿项来克服目标加速度对制导精度的影响.将该方法运用于机动目标的跟踪,仿真结果表明了增广比例导引律相比于传统比例导引律,制导精度高,脱靶量低,制导飞行时间短,制导性能有极大的提高. 相似文献
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某型歼击机远距导航效能的计算 总被引:1,自引:0,他引:1
导航效能是影响飞机总体作战效能的关键因素之一。本文研究了某型歼击机导航阶段的导航效能模型,给出了导航效能的计算方法和程序框图,为最终评估歼击机的综合作战效能提供理论依据。 相似文献
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针对基于图像分割的室内视觉导航地图创建方法存在无法准确获取导航地图等问题,提出一种利用激光投射的创建方法。在室内天花板上安装激光发射装置,通过激光光斑在图像中实际位置与预测位置的差计算投射区域的高度,利用获得的高度信息创建导航地图。搭建了验证导航地图创建算法的实验平台,实验结果表明,本文方法能够获得地面高度分布,可以创建准确的室内导航地图。 相似文献
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Dirk Wenig Stefan Brending Nina Runge Rainer Malaka 《Journal of Location Based Services》2014,8(3):179-197
Studies in the field of pedestrian navigation have shown advantages of map–image combinations. While in a previous work, the map view was either replaced with an image view in predefined situations, or the user was required to manually switch between both views, we suggest to use a split screen displaying maps and images at the same time. We developed two variants, one employing panoramic images aligned to the mobile device's orientation and the other using simple photographs, and we evaluated both against manual switching in a field study. While none of the interfaces outperformed the other, results indicate advantages of panoramic images independent of manual switching or the split screen. 相似文献
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优秀的路标设计,可以简化路标识别算法并提高机器人定位与导航的准确性和实时性。本文针对结构环境下的视觉导航系统,设计了一款多功能路标并给出了相应的应用算法。通过综合考虑拓扑结构、几何结构和色彩选取等的优化,设计的路标可以提供丰富的信息,而且具有较强的抗干扰能力。基于所设计的路标可以实现基于单帧图像中单个路标的机器人定位与导航,以及在大范围内基于序列路标的导航,并且可以准确估计序列路标中下一路标的位置。在具有较多干扰因素的大厅和走廊中进行的机器人定位与导航实验表明,即使采用未经校正的鱼眼镜头,机器人定位误差最大仍不超过5cm,示教再现导航误差最大不超过10cm;且在长距离导航实验中可实现方便、准确进行路标切换,有效提高导航的实时性和抗干扰性,证明了所设计路标的有效性。 相似文献
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随着GPS车载导航系统的普及,围绕车载导航系统性能的研究主要集中在了如何提高导航精度的问题上.然而,车载导航应用的特殊环境决定了传统的精度提高方法的局限性.文中首先简述了车载导航的特殊环境,然后在此基础上提出了利用EM(Expectation Maximization,期望最大化)算法提高导航状态解算精度的构想.通过使用平淡卡尔曼滤波,解决了期望最大化两步算法中的第一步即状态估计问题.基于实测数据的仿真结果证明,该方法能够有效地提高车载环境下接收机的定位精度和稳定性,进而提高车载导航的服务质量. 相似文献
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《Journal of Location Based Services》2013,7(3):213-237
ABSTRACTThe characteristics of a smartwatch impose several challenges regardig the design of a pedestrian navigation aid. This paper illustrates how landmark-based pedestrian navigation systems for smartwatches can be developed, considering the small screen sizes as well as the very limited interaction capacities of these wrist-worn devices. Particularly, by the use of a user-centred design approach, an initial user interface was developed, tested, and refined in two field experiments to create a final user interface. A combination of map view and direction view was proposed, where the map view provides an overview of the environment and route, while the direction view gives clear instructions (turning information) for decision points. The interface was further enhanced by the use of vibrations before decision points. In addition, landmarks were carefully considered and incorporated into both map view and direction view. The field experiments showed that these key features of the revised interface can effectively support pedestrian navigation via smartwatches. 相似文献
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With the development of the Ground Positioning System (GPS) modernization and the expectable implementation of Galileo, people pay more and more attention to civil applications on multi-frequency signals. This paper proposes a new and advanced positioning algorithm for the dual-frequency satellite navigation receivers, concerning the various influences of all the ranging error sources and taking advantage of the Klobuchar single-frequency ionospheric model. The paper also presents positioning precision prov... 相似文献
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介绍了水下滑翔机定位导航的特点,提出了水面-水下导航定位算法。通过Matlab进行扩展卡尔曼滤波仿真处理,证明了该算法的有效性及鲁棒性。 相似文献