Three-dimensional multi-constraint route planning of unmanned aerial vehicle low-altitude penetration based on coevolutionary multi-agent genetic algorithm

To address the issue of premature convergence and slow convergence rate in three-dimensional (3D) route planning of unmanned aerial vehicle (UAV) low-altitude penetration,a novel route planning method was proposed.First and foremost,a coevolutionary multi-agent genetic algorithm (CE-MAGA) was formed by introducing coevolutionary mechanism to multi-agent genetic algorithm (MAGA),an efficient global optimization algorithm.A dynamic route representation form was also adopted to improve the flight route accuracy.Moreover,an efficient constraint handling method was used to simplify the treatment of multi-constraint and reduce the time-cost of planning computation.Simulation and corresponding analysis show that the planning results of CE-MAGA have better performance on terrain following,terrain avoidance,threat avoidance (TF/TA2) and lower route costs than other existing algorithms.In addition,feasible flight routes can be acquired within 2 s,and the convergence rate of the whole evolutionary process is very fast.

An Elevated Perspective: Dyke-Related Fracture Networks Analysed with Uav Photogrammetry

An abundance of data from seismic and geodetic monitoring has provided new insight into dyke propagation and emplacement mechanisms.These studies show that faulting and fracturing is part of the magma

Architectural Model of a Dryland Gravel Braided River,based on 3D UAV Oblique Photogrammetric Data:A Case Study of West Dalongkou River in Eastern Xinjiang,China

Three-dimensional unmanned aerial vehicle(UAV)oblique photogrammetric data were used to infer mountainous gravel braided river lithofacies,lithofacies associations and architectural elements.Hierarchical architecture and lithofacies associations with detailed lithofacies characterizations were comprehensively described to document the architectural model,architectural element scale and gravel particle scale.(1)Nine lithofacies(i.e.,Gmm,Gcm,Gcc,Gci,Gcl,Ss,Sm,Fsm and Fl)were identified and classified as gravel,sand and fine matrix deposits.These are typical depositional features of a mountainous dryland gravel-braided river.(2)Three architectural elements were identified,including channel(CH),gravel bar(GB)and overbank(OB).CH can be further divided into flow channel and abandoned channel,while GB consists of Central Gravel bar(CGB)and Margin Gravel bar(MGB).(3)The gravel bar is the key architectural element of the gravel braided river,with its geological attributes.The dimensions of GBs and their particles are various,but exhibit good relationships with each other.The grain size of GB decreases downstream,but the dimensions of GB do not.The bank erosion affects the GB dimensions,whereas channel incision and water flow velocity influence the grain size of GB.The conclusions can be applied to the dryland gravel braided river studies in tectonically active areas.

High Spatial Resolution Mapping of Dykes Using Unmanned Aerial Vehicle(UAV) Photogrammetry: New Insights On Emplacement Processes

Remote sensing has played a pivotal role in our understanding of the geometry of dykes and dyke swarms on Earth,Venus and Mars(West and Ernst,1991;Mege and Masson,1995;Ernst et al.,2005).Since the 1970’s

A method to interpret fracture aperture of rock slope using adaptive shape and unmanned aerial vehicle multi-angle nap-of-the-object photogrammetry

The aperture of natural rock fractures significantly affects the deformation and strength properties of rock masses,as well as the hydrodynamic properties of fractured rock masses.The conventional measurement methods are inadequate for collecting data on high-steep rock slopes in complex mountainous regions.This study establishes a high-resolution three-dimensional model of a rock slope using unmanned aerial vehicle(UAV)multi-angle nap-of-the-object photogrammetry to obtain edge feature points of fractures.Fracture opening morphology is characterized using coordinate projection and transformation.Fracture central axis is determined using vertical measuring lines,allowing for the interpretation of aperture of adaptive fracture shape.The feasibility and reliability of the new method are verified at a construction site of a railway in southeast Tibet,China.The study shows that the fracture aperture has a significant interval effect and size effect.The optimal sampling length for fractures is approximately 0.5e1 m,and the optimal aperture interpretation results can be achieved when the measuring line spacing is 1%of the sampling length.Tensile fractures in the study area generally have larger apertures than shear fractures,and their tendency to increase with slope height is also greater than that of shear fractures.The aperture of tensile fractures is generally positively correlated with their trace length,while the correlation between the aperture of shear fractures and their trace length appears to be weak.Fractures of different orientations exhibit certain differences in their distribution of aperture,but generally follow the forms of normal,log-normal,and gamma distributions.This study provides essential data support for rock and slope stability evaluation,which is of significant practical importance.

UAV倾斜摄影在革命旧址保护中的应用

针对革命旧址保护工作的严峻性,以及在获取革命旧址测区数据中传统测绘方法工作效率低、难以全面获取数据和无法获得高精度三维立体数据等问题,基于UAV倾斜摄影测量技术,以红军长征旧址为研究对象,通过外业数据采集,利用SIFT算法提取匹配影像特征点,再利用SfM-MVS算法构建三维立体场景,采集三维立体场景中的检查点数据。结果表明,三维立体场景满足大比例尺数字地形图成图规范要求;分析线元素精度可知,三维立体场景数据测量结果可达厘米级,满足革命旧址保护中对数据精度的要求;在革命旧址保护工作中还可提供多种基础数据,为今后革命旧址保护工作提供了一种高效获取高精度数据的参考方法。

基于UAV与ADCP航测地形数据的河道高精度模拟应用

采用无人机和ADCP无人船对湖南省境内资江某河段进行航测,将得到的地形高程数据(DEM)插值到计算网格中,通过对该河段进行数值模拟,可得到该河段某一时刻的流场及水位变化情况。基于UAV与ADCP航测地形数据的河道高精度模拟可用于河道的通航论证、防洪评价等,将为相关河道工程建设提供数据支撑与参考。

基于UAV摄影测量技术的开采沉陷全盆地建模和求参

以内蒙古唐家会矿区为研究对象,获取该地区2020年8月与2021年3月无人机摄影影像数据,并制作生成DEM,将2期DEM数据相减获取该地区下沉盆地,用BP神经网络算法作去噪处理,并对比不同去噪方法的去噪效果;利用全盆地下沉数据,融合模拟退火算法(SA)与概率积分参数反演方法,求出该下沉盆地下沉系数与主要影响角正切;利用该参数模拟下沉盆地,计算出测量中误差为589 mm,占最大下沉值8.1%;最后对参数作抗差分析,在测量中误差占(1%~10%)最大下沉值时,求参结果可靠。结果表明:BP神经网络算法能够有效去除盆地内噪点,提高下沉盆地的精度,基于SA和矿区全盆地数据能够有效求取概率积分参数,弥补无人机精度不高带来的影响。

Application of UAV in Road Safety in Intelligent Areas

With the continuous development of remote sensing(RS)technology,the surface information can be collected conveniently and quickly by using the popular unmanned aerial vehicle(UAV).The application of UAV low altitude RS technology in road safety in intelligent area has certain practical significance.It can provide safety warning for most drivers,and provide auxiliary decision-making for the road supervision department.Through the collection,processing,calculation and analysis of the road image,the UAV can find out the road obstacles with potential safety hazards,identify the road pit,calculate the radius and depth of the road pit through the digital mapping system,predict the accident risk according to different speed and provide scientific basis for the road safety monitoring.At the same time,UAV can provide repair scheme for damaged roads,estimate the quantity of materials needed for repair,and achieve the target of resource saving and efficiency improvement.The experimental results show that the UAV can not only provide scientific prediction information for driving safety,but also provide relatively accurate material consumption for road repair.

Using UAVs for detection of trees from digital surface models

A difficult problem in forestry is tree inventory.In this study, a GoProHero attached to a small unmanned aerial vehicle was used to capture images of a small area covered by pinus pinea trees. Then, a digital surface model was generated with image matching. The elevation model representing the terrain surface, a ‘digital terrain model’,was extracted from the digital surface model using morphological filtering. Individual trees were extracted by analyzing elevation flow on the digital elevation model because the elevation reached the highest value on the tree peaks compared to the neighborhood elevation pixels. The quality of the results was assessed by comparison with reference data for correctness of the estimated number of trees. The tree heights were calculated and evaluated with ground truth dataset. The results showed 80% correctness and 90% completeness.

基于无人机倾斜摄影测量三维建模的区域黄土滑坡识别及特征分析

【研究目的】黄土滑坡是黄土地区人居与城镇建设安全的重大隐患。滑坡识别是滑坡灾害及其他研究工作的基础,因此基于无人机倾斜摄影测量三维建模从不同维度、不同视角直观快速地识别黄土滑坡并进行特征参数提取,能够为黄土滑坡风险识别及风险管理精细化研究提供技术支撑。【研究方法】以宁夏回族自治区固原市彭阳县红河镇西南部的黑牛沟村为研究区,采用无人机倾斜摄影测量数据获取、三维建模、现场验证结合地统计学分析,开展了区域黄土滑坡识别及其特征参数提取和分析。【研究结果】基于三维实景模型确定并分析研究区沟谷沿线地貌凹陷区是否存在陡壁及其周界形态,结合色调、纹理和微地貌等标志实现了黄土滑坡识别,共圈定了23个滑坡,结合现场验证移除2个非滑坡点,最终确定了21个滑坡;滑坡密集分布在主沟和支沟沟口,多呈对滑的形式出现在沟谷两侧且具有群发性;大型及特大型滑坡占比达到57.14%,滑坡的滑动方向主要以西南(阳坡)、东南(半阳坡)为主,相对高差集中在80~120 m,滑坡体坡形多呈凹形坡,滑坡体坡度主要集中在20°~30°;滑坡体土地利用类型主要为植被,其次为裸地,也有一部分为农田,道路和河流占比极少。【结论】基于无人机倾斜摄影测量构建的三维实景模型可从多维度、多视角精确快速地识别区域黄土滑坡,并分析其相关特征参数,能够弥补当前二维平面遥感影像存在的不足;还能够为滑坡易发性、危险性、易损性及风险评估等相关研究提供数据支撑。

基于无人机倾斜摄影测量技术与SVR算法的开采沉陷监测与预计

为实现矿区开采沉陷高精度监测与预计,将无人机倾斜摄影测量技术与支持向量回归算法(Support Vector Regression Algorithm,SVR)相结合,对赤峰市六家煤矿采区沉降量进行了监测与预计,并将预计结果与GPS实测结果进行了对比。结果表明:GPS实测矿区10 d测量沉降量为0.2~15.8 mm,东西南北区平均沉降量分别为51.2、31.5、46.6、130.8 mm,北侧沉降量分别为东、西、南侧的2.55、4.15、2.81倍,矿区北侧为沉降严重区,需要进行重点监测并制定合理有效的防治措施。基于无人机倾斜摄影测量技术与SVR算法预测的矿区东西南北区累计平均沉降量分别为49.4、31.5、45.8、134.6 mm,所有测点2种测量方式所得相对误差均在5%以内,反映出所提方法预计精度较高,为实现矿区开采沉陷高精度监测与预计提供了参考。

3D modeling of Unmanned Aerial Vehicles Tilt Photogrammetry

Unmanned Aerial Vehicles(UAV)tilt photogrammetry technology can quickly acquire image data in a short time.This technology has been widely used in all walks of life with the rapid development in recent years especially in the rapid acquisition of high-resolution remote sensing images,because of its advantages of high efficiency,reliability,low cost and high precision.Fully using the UAV tilt photogrammetry technology,the construction image progress can be observed by stages,and the construction site can be reasonably and optimally arranged through three-dimensional modeling to create a civilized,safe and tidy construction environment.

基于UAV影像像控点选点方法探讨

低空无人机航摄是一种新型的低空遥感影像数据获取方式,其像控点布设、选刺是无人机影像数据生产的重要环节。尤其在地形复杂测区会增大外业刺点数量,不仅影响内业加密精度,更影响整个项目进度。针对这些问题,本文提出一种布设像控点的新思路,灵活利用常规测量小软件并结合多种技术手段,来提高外业像控点选刺效率。通过具体项目验证该方法的可靠性,这样既能提高外业像控点的选刺效率,也能保证内业加密精度要求。为以后类似项目实施提供较强的借鉴意义。

无人机倾斜摄影在土地调查中的应用

【目的】在我国土地调查发展过程中,常因技术手段存在缺陷,导致调查工作受到一定的影响。利用无人机倾斜摄影技术来建立实景三维模型,通过三维模型来完成相关调查工作,使土地调查工作更加高效、便捷。【方法】为探讨无人机倾斜摄影技术在土地调查工作中的应用优势,使用无人机搭载单目相机来采集影像,利用ContextCapture Center软件进行三维建模,并与实际调查结果进行对比,分析三维模型的优缺点。【结果】结果证明了该方法的可行性,建立的三维建模的土地边界清晰、建筑分明,可应用到土地调查工作中。【结论】无人机倾斜摄影技术可提高土地调查工作的完成效率,同时为我国未来的国土调查等工作提供支持。

无人机倾斜摄影测量在城市竣工测量中的应用

文章以无人机倾斜摄影测量技术作为切入点,分析该技术的测量原理、应用特点和系统组成结构,加强对无人机倾斜摄影测量技术的全面掌握,奠定技术应用推广基础。并重点阐述无人机倾斜摄影测量技术在城市竣工测量项目中的实践应用方法,以测量流程步骤、操作要点、注意事项作为阐述重点。旨在依托无人机倾斜摄影测量来打造新一代城市竣工测量技术体系,推动测量水准、作业效率和成果质量全面提升。

无人机倾斜测量在大比例尺地形图绘制中的应用及精度分析

无人机倾斜测量技术应用于大比例尺地形图绘制中不仅可以提高工作效率、节约人力物力成本,更能克服人工测量受地形限制的不足。为了探究无人机倾斜摄影测量多个维度精度,在无人机航测系统基本原理分析基础上,研究了航测系统误差来源和误差评定标准,通过以某村庄航空摄影测量进行试验,对无人机倾斜测量的点位精度、高程精度、长度精度和面积精度进行了系统分析。结果表明:无人机倾斜测量的多个维度精度均满足要求,该技术方法适用于大比例尺地形图绘制。

无人机倾斜摄影测量技术在林区植被恢复治理中的应用

林区植被破坏后,需要对破坏区域进行测量评估再实施恢复治理。林区由于树林的遮挡,存在通视困难。信号障碍等难题,使用传统的全站仪、GPS测量方法采集数据较为困难,本文提出,依靠无人机倾斜摄影测量模式获取空间数据,再通过三维建模,最后生成各类成果数据文件。项目实例应用证明本文的测量方法和模式有效,效果良好。

摄影测量局部场景稳健合并的并行式运动恢复结构方法

针对并行式运动恢复结构(SfM)在局部场景合并时稳健性差的问题,提出一种摄影测量局部场景稳健合并的并行式SfM方法。对整个场景的影像关联图进行分块及扩展处理,得到相互重叠的子区块,并利用一种改进的增量式SfM方法生成局部场景重建结果。在局部场景合并时,首先利用局部场景的重叠关系构建子区块关联图,并以子区块三元组为单元,进行粗差剔除;然后,利用子区块三元组的代数性质,优化得到更符合几何一致性的子区块间的相对变换;最后,从上述结果中计算得到更准确的局部场景到统一坐标系下的尺度、旋转、平移变换。试验采用无人机影像,结果表明本文方法在局部场景合并时有更好的稳健性,而且SfM结果的精确度也要优于其他并行式方法和COLMAP,在摄影测量和实景三维重建中有较大的应用潜力。

无序无人机影像的并行化SfM三维重建方法

增量式运动恢复结构(ISfM)已成为无人机影像三维重建的关键技术。然而,大数据量、大重叠度和高分辨率的无序无人机影像导致的匹配对检索代价大、迭代优化误差累积和效率低的问题,使其难以满足大场景ISfM处理需求。本文提出联合全局描述子和图索引的无人机影像并行化SfM方法。针对影像特征数量大、影像检索编码本尺寸增加导致的匹配对检索效率低的问题,设计了联合全局描述子和图索引的高效影像检索方法,从而加速影像匹配。针对分块并行化SfM子场景合并存在同名点搜索效率低、内存消耗大、合并解算精度低的问题,设计了基于按需匹配图和双向重投影误差的子场景合并方法,实现无人机影像的并行化SfM重建。利用不同场景、不同采集方式获取的真实无人机影像进行试验,结果表明本文方法能够实现36~108倍加速比的匹配对检索,ISfM重建效率达到30倍加速,且相对定向和绝对定向精度与传统方法相当。