无人飞行器低空摄影技术探讨

陕西省第二测绘院自2007年关注利用无人机进行航空摄影测量,2008年在陕西凤翔县,“中兵光电公司”合作试验,按测量规范的标准生产出1:2000的正射影像地图15Km2.本文以我们实践体会,就“无人机摄影测量”的推广应用中遇到的问题,以测量用户的角度提出推进建议.     

小型无人机航线编制研究

小型无人机飞行技术目前在国内处于初步但迅速发展时期,对无人机的控制不仅体现在本身的硬件性能上,更体现在对其的操纵控制技术上.本文概述基于Google Earth COM API和KML的无人机飞行控制:在Google的三维数据基础上,实现“世界范围”内的飞行控制,具体描述航线航点的编码绘制方法与显示,提供便利的航线添加编辑修改删除等功能.     

无人机航测带状地形图的试验及分析

本文结合高速公路建设勘察,采用无人机数码航空摄影测量系统进行航测制图,以试验大比例尺带状地形图的航测方法及其精度。结果表明,在常规控制布点条件下,基于单台普通数码相机摄影的无人机作业,能够满足对成像比例尺放大10倍测图的平面精度要求,但尚不能达到相应的高程精度要求;准确消除普通数码影像系统误差是提高该技术航测精度的关键。     

基于无人机航摄影像的数字线划图生成方法

数字线划图(DLG)是国家与城市建设中重要的基础数据源,传统测绘作业数据作为DLG生产的基础,存在产品误差较大,产品质量得不到保证的缺点. 本文基于无人机航摄影像进行DLG产品制作研究,实施了一种快速生成DLG产品的方法,通过质量分析和结果检验,证明了该方法的可行性.      

无人机高空间分辨率影像分类研究

本文利用无人机影像进行土地利用类型研究,面向对象方法对影像分割,获取了最佳分割尺度;根据各土地类别的特征信息建立分类定义,提出了快速、准确获取土地利用类型的方法。研究结果表明,运用面向对象方法能很好地解决无人机高分辨率影像分类问题,其中关键是影像分割尺度的选择和影像对象特征信息的提取。     

大区域无人机影像数据的快速几何处理

无人机遥感影像快速几何处理被广泛应用于灾害应急监测与评估、军事侦察等领域。针对目前多数商业软件所依赖的硬件平台成本昂贵、软件开发过程复杂等问题,面向通用硬件平台,提出一种大区域无人机影像数据的快速几何处理方法。对制约处理效率的各关键算法进行优化和改造,实现大区域无人机影像数据的快速几何处理;在影像连接点匹配、正射纠正和影像镶嵌的处理过程中,均应用基于多核CPU并行处理技术,提高整体处理效率。多组无人机影像数据处理试验表明,该方法能够大幅提高处理效率,对硬件平台要求低,具有推广应用价值。     

Monitoring household upgrading in unplanned settlements with unmanned aerial vehicles

In-situ slum upgrading projects include infrastructural improvements such as new roads, which are perceived to improve the quality of life for the residents and encourage structural improvements at a household level. Although these physical changes are easily visible in satellite imagery, it is more difficult to track incremental improvements undertaken by the residents – which are perhaps more closely linked to the socio-economic development of the households themselves. The improved detail provided by imagery obtained from Unmanned Aerial Vehicles (UAVs) has the potential to monitor these more subtle changes in a settlement. This paper provides a framework which takes advantage of high-resolution imagery and a detailed elevation model from UAVs to detect changes in informal settlements. The proposed framework leverages expert knowledge to provide training labels for deep learning and thus avoids the cost of manual labelling. The semantic classification is then used to interpret a change mask and identify: new buildings, the creation of open spaces, and incremental roof upgrading in an informal settlement. The methodology is demonstrated on UAV imagery of an informal settlement in Kigali, Rwanda, successfully identifying changes between 2015 and 2017 with an Overall Accuracy of 95 % and correctly interpreting changes with an Overall Accuracy of 91 %. Results reveal that almost half the buildings in the settlement show visible changes in the roofing material, and 61 % of these changed less than 1m². This demonstrates the incremental nature of housing improvements in the settlement.     

无人机遥感技术现状与应用

随着测绘科学技术的发展,各行各业对遥感数据的需求日益增加,但遥感数据获取手段相对不足。无人机遥感系统以更低的运营成本、高效灵活的任务安排,自动化和智能化的操作应用成为主要的遥感技术之一。本文对目前国内外无人机遥感的研究现状进行了介绍,在此基础上对无人机遥感关键技术进行了分析。     

基于最优路径的无人机影像辐射区域网平差

无人机遥感能够提供高时空分辨率的影像数据,拥有广泛的应用前景。辐射校正将传感器记录的数据转化为地表反射率,是无人机数据定量化应用的前提。然而无人机数据易受光照等因素的影响,导致影像间存在不同程度的辐射差异,为多张无人机影像的辐射校正带来困难。基于影像间重叠区域的信息,辐射区域网平差能够获得全局最优的辐射校正参数,降低影像间的辐射差异,因此在实现影像的辐射校正方面具有巨大潜力。但大量待求解未知参数降低了辐射校正模型的求解效率,特别是在数据量急剧增加时,该问题更为突出。基于影像重叠区辐射信息建立的最优路径很好地考虑了影像间的辐射转化关系,可有效控制误差累计,为减少辐射区域网平差中未知参数的数量提供了一种思路。因此,本文将最优路径与辐射区域网平差相结合,以降低待求解参数的数量,在保证辐射校正精度的同时提高辐射校正模型求解效率,进而提升辐射区域网平差在大数据集上的应用潜力。     

无人机三维空气质量监测研究

针对现有空气监测缺乏污染垂直分布特征的观测及数据采集覆盖范围有限的问题,该文提出了用无人驾驶飞机搭载微型空气质量检测器监测大气污染的方法,首先分析了传统地面监测站的缺点,并阐述了监测设备的构成;然后从无人驾驶飞机大气污染空间采样方案、污染物数据的准确性及可靠性校正、大气污染时空规律几个方面做了研究;最后选择浙江省临安市青山湖街道、上海奉贤区等地区进行了试验。研究结果能有效补充地面监测站的数据缺失,揭示PM2.5、O3等大气污染物的垂直分布、垂直扩散及区域性输送特征,为空气污染预警和防控对策机制的制定提供重要技术依据。     

无人机近红外遥感初探

针对无人机有效载荷的限制,目前可用于无人机的传感器单一,数据覆盖波段只局限于可见光这一问题,该文着眼于无人机搭载的近红外相机进行遥感应用研究。通过无人机红外数据与对应卫星数据的应用对比,集成对比因子为归一化差值植被指数(NDVI)和土壤调节植被指数(SAVI),验证无人机获取近红外数据遥感手段的可靠性,说明了该文提出的无人机红外数据获取方法可用于数据获取以及相应的遥感应用,对未来无人机遥感技术的深入发展提供一定的参考。     

Role of aerial photographs and landsat imagery in forest resources surveys

Many of the data needs for efficient management of forest resources can be met by aerial photographs. Commercially important tree species can be distinguished from other less important miscellaneous species with the help of aerial photographs. Forests can be classified according to their height and density classes. Aerial photographs have become indispensable for mapping of forests and preparation of forest inventories. A comparison of interpretation results obtained from landsat imagery and aerial photographs (1 ∶ 10,000 Black and White panchromatic photography) with respect to forestry interpretation is given. It is pointed out that the imagery obtained from satellities can be used for reconnaissance of a region and for deciding the priorities for carrying out more detailed surveys of forest resources with the help of air photointerpretation techniques     

基于六旋翼无人机平台的GNSS干扰源测向与定位系统设计与实现

目前,基于无人飞行器的导航干扰源探测方面的研究主要集中在理论研究与仿真实现阶段[1],文中设计了一种基于六旋翼无人机平台的全球卫星导航系统(GNSS)干扰源测向与定位系统, 并在某飞行场区进行了干扰源定位精度的测试. 该系统主要由六旋翼无人飞行器、干扰源监测测向载荷以及地面站组成. 系统试制完成后,选定开阔环境,通过设置干扰源发射不同的调制方式、不同发射功率的干扰信号,以此来验证干扰源的定位精度.      

改进支持向量机算法无人机影像信息精确提取

支持向量机(SVM)算法作为一种成功应用于大多数遥感影像的分类方法,虽然具有较高的提取精度,但是针对分类中仅仅采用单一参数,严重依赖于参数选择的不足,该文基于AdaBoost算法提出一种改进的SVM分类方法。该方法采用选择径向基函数作为核函数的SVM算法作为AdaBoost的弱分类器,实现了核参数的自适应调整。实验结果证明,该方法可以达到精确提取无人机影像信息的目的。     

Geomorphometry and microelectronic metrology: Converged realms

This article discusses the application of geomorphometric methods in microelectronic metrology. Six typical microelectronic items were geomorphometrically analyzed using their digital elevation models with nano- and micrometer-range resolution and elevation difference: (1) a silicon–quartz structure; (2) a mechanically polished silicon wafer; (3) a photovoltaic blend sample; (4) an X-ray optical element (a fused quartz spherical concave substrate); (5) a Bosch process-formed, 20 aluminum layered membrane; and (6) a silicon–glass assembly with a volumetric defect. Geomorphometric modeling increases significantly the visibility and informativeness of data presentation, allowing to identify effectively the spatial distribution of nano- and microforms of the surface of microelectronic items. Geomorphometric methods provide an opportunity to study the size, location, and characteristic features of nano- and microtopographic inhomogeneities of microelectronic items using maps of minimum, maximum, mean, and unsphericity curvatures as well as other morphometric variables.     

无人机倾斜摄影结合激光扫描仪三维逆向建模

近年来随着科学技术水平的不断提高,城市三维数字化成为数字城市建设的重点应用方向.无人机遥感技术、三维激光扫描技术的发展,使数字城市建设逐渐开始向全面自动化、智能化转变.本文利用拓普康猎鹰8号多旋翼无人机,并结合拓普康GLS-2000L三维激光扫描仪对建筑物进行数据采集,然后利用Context Capture自动建模后处...     

无人机空地一体三维激光扫描技术应用研究

首先对三维激光技术的概念、发展及空地一体扫描技术的研究背景进行了分析,然后对空地一体扫描技术进行定义并对空地一体扫描技术的特点进行了总结,最后对其应用进行了研究。经过实地操作,基于无人机的空地一体三维扫描技术可以有效克服传统扫描方式弊端,实现高精度立体监测网络(空中-地面-地下监测),完成多载荷数据获取平台:机载-车载-室内、机载-车载-室内知识产权系列产品等。     

A methodology for semi detailed soil surveys using medium scale aerial photographs

A methodology for the preparation of semi detailed soil maps using medium scale aerial photographs for an area of about 3600 ha in Merida area, Spain is presented. The new concepts such as ‘Basic Land Units’, ‘Soil Consociation’ and ‘Soil Set’ developed by Elbersen (1976) were adopted for this study to see their utility for the preparation of semidetailed soil maps which can be used for land evaluation, land classification and also for making prodictions about the feasibility of a particular project for rural development plannning purposes. Basic land units and their subdivisions like major and minor compo-nents were used for the delineation of interpretation units. Mapping units, viz, Soil Consoication, Soil Complex and miscellaneous land type were used for mapping soils. Soils were classified upto family level and shown as subgroups in the 1:50,000 scale soil map. Soils were mapped as soil sets per basic land unit per subgroup. A model legend for use in the preparation of seimdetailed physiographic cum soil maps is given which is in terms of physiography and Soil Taxonomy qualified by soil sets.     

无人机红外传感器改制及数据获取研究

针对云雾复杂气候条件下无人机可见光影像难以获取的问题,文章在分析了地质灾害应急遥感监测伴随的复杂气候条件的基础上,根据目前无人机传感器的构造原理,通过对各种红外滤片的分析和比较,研究基于红外滤片元器件的无人机传感器红外改制技术和红外影像数据增强方法,对航摄传感器进行红外改装。实验结果表明,无人机红外传感器在多云雾条件下能够获取高精度清晰影像,有效解决云雾条件下地质灾害应急数据获取难题,为地质灾害应急决策提供参考。