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Feng Wenhao 《地球空间信息科学学报》2013,16(4):66-72
The purpose, classification, required accuracy and surveying methods of control work for close range photogrammetry have been briefly stated. The different methods for definition of space, object coordinate system are also reviewed. It is suggested that the habitu-ally-practised rotation angle system for aerophotogrammetry in China should be used for the future teaching and resaarching work in the close range photogrammetry, and that the rotation angle system for terrestrial deformation photogrammetry should be left out in order to avoid the confuse and reduce the amount of expanse for making softwares. It has been emphasized that there are three improtant aspects in the close range control work with high accurary using the conventional method of engineering surveying: the use of standard scale for measurement of distance between two general stations, the accurate determination of start direction line between two general stations and the handling method of influence of 2C change. A method for setting up industrial surveying control net with extra-high accuracy ±(0.05–0.20) mm is presented by the author. This kind of industrial control net is necessary for batch process of large industrial components with purposes of measurement, inspect and lofting. There are some special methods of control work in the close range photogrammetry, including two methods presented by the author. 相似文献
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Since the earliest days of photogrammetry, there have been photogrammetrists who have directed research effort towards medical measurement. Although the specific motivation for these studies has not always been disclosed, it is probably because of the various benefits that photogrammetry can offer to humanity as a painless and non-invasive means of providing medical practitioners with spatial measurement relating to the human body. The intention of this paper is to reflect on the place of the many medical developments within the photogrammetric world. The various photogrammetric applications in medicine are summarised to identify the characteristics of medical photogrammetry, and it becomes evident that medical photogrammetrists have developed a range of body measurements using widely varying photogrammetric techniques, in response to the demands for specialised spatial measurement tools for a wide variety of medical ends. This volume of research activity has made medical measurement a substantial and varied sector of non-mapping photogrammetry. It is also clear that there are numerous challenges to the design of medical photogrammetric systems. They must give paramount consideration to the human patients and their comfort; they must yield not simply spatial data about the body but rather specific medical information. At the same time, it is of concern that non-photogrammetric scientists and engineers have developed medical measurement systems based on both photogrammetric and other optical techniques. Fortunately, photogrammetrists can also contribute to medical problems through their spatial data experiences. It is concluded that the many distinctive challenges mean that medical photogrammetry has not yet been as successful at changing the world as the extensive efforts applied to it suggest, but nevertheless, medical photogrammetry deserves to be recognised as a category of close range photogrammetry which remains a valuable pursuit which should not be abandoned because of any difficulties. 相似文献
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Over the past decade, photogrammetry has been increasingly applied as a precise three dimensional measuring tool in industrial and engineering works. Analytical photogrammetry is now routinely employed in tasks of measurement as diverse as machine tool inspection and fixture checking, structural deformation monitoring, the provision of control databases to guide industrial robots and the measurement of structures in earth orbit. Traditional photogrammetric techniques and instrumentation are usually inappropriate for industrial work and the development of complete, fully integrated close range photogrammetric systems has recently gained considerable impetus. This paper details some of the significant new developments in industrial photogrammetry, with particular reference to technological advances in the Simultaneous Triangulation and Resection System (STARS) designed by Geodetic Services, Inc. for industrial photograininetry. Practical aspects of industrial measurement are also presented in a review of some of the varying tasks that GSI has carried out in recent years. Emphasis is placed on demonstrating the flexibility, accuracy, reliability and economy of photogrammetry, as well as the progress made in automating this measurement technique. 相似文献
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FENG Wenhao 《地球空间信息科学学报》2001,4(4):66-72
1 IntroductionByvirtueofthecontrolpointsand/orrelativecontrolwork ,themainobjectiveofcontrolsurvey ingincloserangephotogrammetryistobringthecloserangephotogrammetricnetunderthespeci fiedobjectspacecoordinatesystem .Besidesthese lectionofobjectspacecoordi… 相似文献
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三维可视化工程设计的研究 总被引:12,自引:0,他引:12
首先提出利用正射影像及其立体匹配片组成的立体正射影像对作为建立地形三维立体模型的基础,并介绍了立体匹配片的原理,接着实现了两种类型立体匹配片的制作和镶嵌,利用镶嵌之后的正射影像及立体匹配片可以构建大范围地形的三维立体模型,从而建立三维工程设计平台应用于工程设计,并对该平台的量测性能进行了测试,最后介绍了该技术在输电线路设计、交通线路设计等具体工程设计领域的实际应用。 相似文献
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R. Clayton 《The Photogrammetric Record》1989,13(73):27-62
A review is provided of the techniques and applications of very close range photogrammetry to engineering measurements in the electricity supply industry. Starting from a definition of very close range photogrammetry by consideration of depth of field, the techniques of measurement in the range 300 mm to 3 m are discussed with an analysis of four practical examples; two examples relate to the confirmation of continued structural integrity of nuclear reactor components by remote photogrammetric measurement, one uses the technique for measuring creep stress for component life assessment and one uses it for the baseline measurements of insulation coverplates in a nuclear reactor pressure vessel. Emphasis is given to the mathematical modelling of the cameras employed and their subsequent calibration. The development of a universal calibration facility for all cameras working in this range is described. 相似文献
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无地面控制点条件下, 卫星摄影测量研究与工程实践是世界各国在该领域中所面临的研究难点之一。本文介绍了在无地面控制条件下光学卫星摄影测量的研究发展和工程实践历程, 并对中国“天绘一号”卫星获取的影像实测结果进行分析, 结果表明, 中国在无地面控制条件下的卫星摄影测量研究与工程实践已居于国际领先地位。 相似文献
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为探究不同测量方法获取浅沟数据的精度,本文以元谋干热河谷区浅沟为例,采用RTK、三维激光扫描、近景摄影测量等多种测量方法获取浅沟数据,建立DEM并提取浅沟形态参数,对比近景摄影测量以不同方式获取标记坐标后建立DEM的差异,同时以测针板实测浅沟横剖面为参照,对比分析不同测量方法获取浅沟横剖面的精度。结果表明:RTK获取密度较低的点数据,建立的DEM较粗糙,仅体现沟缘大致走向;近景摄影测量+RTK方法测得的DEM高程整体低于近景摄影测量+全站仪所得DEM高程;利用三维激光扫描仪和近景摄影测量+全站仪两种方法获取数据所提取的浅沟形态参数精度较高;对比浅沟横剖面,横剖面近景摄影测量+全站仪测量所得与实测横剖面重合度较高。因此,利用近景摄影测量+全站仪进行浅沟测量,在精度、效率等方面优势较大。 相似文献
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倾斜摄影测量技术具有高精度、大范围等特点,可以在复杂的场景下实现高性能的测绘数据处理.本文对倾斜摄影测量技术进行了说明,阐述了倾斜摄影测量的工作原理及流程,并结合水利工程测绘项目深入浅出地分析了倾斜摄影测量生成实景三维模型在实际工作中的应用和优势. 相似文献
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B. P. Wrobel 《The Photogrammetric Record》1991,13(77):765-776
The evolution of digital photogrammetry from analytical photogrammetry is outlined, partly by considering the methods employed, but with the main emphasis on mathematical and physical principles. A fundamental distinction is obvious from the nature of the primary information measurement data: the image co-ordinates with analytical photogrammetry and the digital image grey values with digital photogrammetry. For both techniques, appropriate Gauss-Markov evaluation procedures are compared. The relevant relationships between image space data and object space models are presented; radiometric considerations play a more important role than before. The evaluation of digital image grey value data is no longer based on digital image correlation. Instead, a new principle of image inversion has been introduced by directly back-projecting grey values of an image on to object space models. The numerical procedures of digital photogrammetry need some stabilisation by appropriate regularisation elements. The new concept of digital photogrammetry may be applied to imagery from almost any sensor. 相似文献
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倾斜摄影测量技术应用及展望 总被引:6,自引:0,他引:6
倾斜摄影测量技术作为一个新兴的技术方法在三维建模和工程测量中有广泛的前景,文中分析了倾斜摄影测量技术的发展概况、基本原理及外业数据获取,探讨了影像数据的匹配、正射影像纠正以及平差等处理的关键问题并进行总结,详细地介绍了无人机用于倾斜摄影测量的现状及其优越性,对目前倾斜摄影测量精度、存在问题及未来发展进行了描述,通过本文可以快速地了解倾斜摄影测量的技术,并为三维建模提供了一个快速、高效的新方法,展现了倾斜摄影测量技术在测绘领域的巨大潜力。但国内倾斜摄影测量技术仍处于实验和推广阶段,同时还存在一些因素限制其发展,仍需要进一步的研究。 相似文献
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无人机数字航测系统以其快速、灵活、精度高的特点逐渐取代传统的航空摄影测量。本文对UX5无人机数字航测系统在不同航高下测量成果的精度进行分析,寻求精度和效率的平衡点,对工程实际应用提出可行方案。 相似文献
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工业现场近景数字摄影视觉精密测量 总被引:2,自引:0,他引:2
研究了基于近景数字摄影原理的现场三维精密视觉测量方法,对其核心技术:数字成像器件模型及标定、高精度亚像素图像处理算法以及光学编码与精密测头技术进行了深入的讨论,给出了实现思路,为工业现场近景数字摄影精密测量系统的设计提供了理论依据。 相似文献