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1.
HIGH PRECISION INDUSTRIAL PHOTOGRAMMETRY   总被引：1，自引：0，他引：1  
A new high precision photogrammetric system for measurements in industry is presented, which consists of a large format camera and a digital monocomparator. Retroreflecting targets support automatic measurement. Because of a rigorous réseau technique, the system requires lower mechanical effort and fewer costs than conventional systems. It is in operational use in the German and French Airbus Industries.  相似文献   

2.
Preliminary results of an investigation to study the dimensional reliability and potential of small format film products, allied with their use in small format cameras for photogrammetry, are presented. Investigations included analysis of factors influencing both in plane and out of plane deformations. Experiments were conducted using commercially available 70 mm, 120 and 220 film products, processed according to manufacturers’recommendations. Elements of camera design are discussed in the light of results obtained from the measurement of réseau images produced from a modified Hasselblad SWC camera.  相似文献   

3.
The use of small format systems for aerial photography as an alternative to employing the more customary larger 230×230 mm format cameras continues to gain acceptance in a number of applications on the basis of the lower operating costs involved. The reduced costs and relative ease of operation with small format systems can attract unskilled operators who, by producing inferior photographic coverage, may delay the more widespread introduction of smaller systems for photo-interpretation and photogrammetric surveys of local sites. Anticipating the need for a flying and photography specification that would serve the needs of all interested parties, a series of laboratory trials were undertaken in conjunction with a literature review to quantify the comparative image quality performance of both large and small format systems. The spatial resolution of a typical small format system was assessed by photographing a low contrast resolution target using a collimator-based system and also by directly recording the target at a predetermined reduction scale. Comparative results between the two methods of evaluation are assessed and a comparison is made with the performance of larger format cameras.  相似文献   

4.
This paper discusses a method of analytical aerial triangulation which may be carried out on the majority of stereo-plotters. A precise réseau engraved on each plate-holder glass enables a plotter to be used as a réseau stereocomparator. Since the plotter is used merely to measure distances of 1 cm. or less, the projection errors are, to all intents and purposes, eliminated. Test area results indicate an accuracy similar to that obtained with a stereo-comparator. There is no reason why similar results should not be achieved on relatively simple plotters such as the Kern PG2 or the Wild B8.  相似文献   

5.
Conclusions Les différentes méthodes de géodésie spatiale utilisées sur le réseau européen ont prouvé la possibilité d'établir un réseau primaire à grandes milles, entre1500 et2000 kilomètres, avec une précision de3 à5 mètres sur les cordes, et d'environ0″5 sur l'orientation, et peut-être mieux. Le dépouillement complet de l'expérienceRCP 133 pourra confirmer ces chiffres et permettra de vérifier en particulier le facteur d'échelle trouvé. Les méthodes géométriques semblent les plus adaptées à ce travail, mais il serait nécessaire d'atteindre la précision ultime des Lasers:30 cm et d'utiliser les photographies d'écho Laser, l'expérience préliminaire réalisée par l'ONERA étant plus qu'encourageante à ce sujet. Les méthodes semi-dynamiques ont prouvé qu'avec un bon modèle de potentiel, on pourrait retrouver, même à l'échelle d'une portion de continent, la position du centre de gravité de la terre avec une précision d'environ20 mètres. Là encore, on peut espérer mieux: amélioration du modèle, choix de la période de traitement, utilisation d'autres satellites, utilisation de mesures photographiques (pour fixer l'orientation) et Laser. Le réseau constitué par les observations sur Pageos, avec pour échelle la distance San Fernando—Haute Provence, sera déjà une première réalisation de réseaux primaires. Mais il serait probablement souhaitable, à l'occasion du lancement de GEOS-C, d'établir un réseau optimisé et avec le maximum de précision.  相似文献   

6.
Résumé Le problème de la comparison des données obtenues à différentes époques sur un réseau geódésique pour en déduire les déformations subies par ce réseau au cours du temps est discuté, et conduit à proposer un mode de représentation simultané des déformations et des erreurs, utilisant les tenseurs de déformations classiques avec une méthode de Monte Carlo permettant de simuler un grand nombre de séries de mesures.
The repetition of geodetic measurements is employed in many cases to monitor ground deformations, and is widely used for civil engineering, geodynamics and slope instabilities studies. Generally the networks used are small and the main problem to solve is how to detect stable zones, i.e. where the signal/noise ratio of the deformation measurements are below unity. This is commonly done using statistical tests. We present here a new tool, the simultaneous display of the deformations and their related errors, using a classical Monte Carlo methodology when computing strain tensors. Such a representation provides to non-specialists in a quit efficient way the significance level of the deformation patterns. Some examples show that even when statistical test show a poor confidence level, this methodology may give anyway in some situations the pattern of the deformation (but—obviously—not its amplitude).
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7.
Analytical plumbline and serf calibration techniques are applied to the calibration of two underwater cameras: a Rolleifex SLX réseau camera with an Aquamarin WKD-SLX/6006 submarine housing and a Nikonos V underwater camera. The Rolleiflex was fitted with a 50 mm Distagon f/4 lens and the Nikonos with a 28 mm Nikkor-UW f/3.5 lens. Comparisons of the results from the two methods of camera calibration are described. Theoretical differences are predicted for in-air versus in-water values for radial distortion. When these are compared to the actually observed values of distortion, an insight is provided of the precisions claimed for each method of camera calibration.  相似文献   

8.
Small Format Aerial Photography (SFAP) is a new emerging art of acquiring photogrammetric data with metric and non-metric cameras. SFAP with format size normally less than 55×55 mm, possesses the potential of both compiling new maps and updating existing planimetric maps of small areas. Organisations dealing with urban and other large-scale mapping, may be benefited greatly by the use of such data. In the present study, investigations are carried out to update an urban map on scale 1∶10,000 using analytically rectified SFAP from non-metric camera. Results are encouraging and presented in this paper.  相似文献   

9.
SMALL FORMAT AERIAL SURVEYS FROM LIGHT AND MICROLIGHT AIRCRAFT   总被引：2，自引：0，他引：2  
Small format (SF) cameras, fitted to light or microlight aircraft, can provide an economic and convenient alternative to the more expensive conventional mapping systems. Further advantages accrue from the use of wider aperture lenses, an extensive range of easily available films and simplijed processing. These advantages can be exploited by employing light aircraft for small survey missions, such as map revision, and desktop photogrammetric systems dedicated to handling SF imagery. In this paper, an account is given of a research study involving SF map revision survey photography, using a modern microlight aircraft and a 70 mm metric camera.  相似文献   

10.
Résumé Dans une première partie, traitée de fa?on élémentaire, l'auteur, après avoir rappelé diverses solutions particulières, propose deux méthodes pour résoudre le problème de l'optimisation d'un réseau de points de grille sur une sphère, admettant toutes deux une symétrie équatoriale, des points équidistants sur des parallèles régulièrement espacés en latitude, une ligne de points équatoriaux et deux points polaires. Une critique permet de dégager la meilleure de ces deux solutions; cette dernière solution convient, quelque soit le nombre N de points, si N>5, mais conviendra d'autant mieux que N sera plus grand. Une application numérique est donnée pour un réseau de 1.000 points, avec la localisation de ces points sur une carte de l'hémisphère terrestre Nord. Dans une seconde partie, traitée de fa?on plus théorique, l'auteur précise la notion de distance interpoints, montre les limites de validité des solutions précédentes pour finalement proposer une troisième solution, la solution dite “en spirale”, qui lui para?t définitivement la meilleure.  相似文献   

11.
Test field system calibration will be a fundamental part of the future photogrammetric production line. Accurate calibration and performance evaluations are necessary for fully assessing the stability and accuracy of digital sensing techniques. In this paper, a method of comprehensive geometric calibration in a test field has been developed and empirically tested using eight image blocks collected with three UltraCamD digital large format photogrammetric cameras. Permanent photogrammetric test fields form the basis of the method. Important components of the method are determination of system parameters, evaluation of systematic errors, and assessment of geometric accuracy. The results showed that UltraCamD images contained systematic deformations that could not be modeled with single lens additional parameter models. Good point determination accuracy was obtained despite the systematic errors; the typical accuracy was 2–3 μm in image space in the horizontal coordinates and 0.05–0.09‰ of the object distance in height. One of the cameras had significantly poorer performance. In the worst cases, the horizontal accuracy was 5 μm in image space and the height accuracy was 0.18‰ of the object distance. The analog cameras gave better results than the UltraCamD, but the development of appropriate mathematical models for UltraCamD as well as improvements in digital sensors may change the situation in the near future.  相似文献   

12.
利用小型低空航摄平台和非量测小相幅相机,搭载动态GNSS/INS组合系统进行空三加密,研究无人机搭载GNSS/INS辅助在不同分辨率、不同基线数量条件下的像控点布设以及空三加密,并对其平面精度、高程精度进行分析,以实现利用少量地面控制点进行大比例尺地形图测图。  相似文献   

13.
Geometric test field calibration of digital photogrammetric sensors   总被引：1，自引：0，他引：1  
Test field system calibration will be a fundamental part of the future photogrammetric production line. Accurate calibration and performance evaluations are necessary for fully assessing the stability and accuracy of digital sensing techniques. In this paper, a method of comprehensive geometric calibration in a test field has been developed and empirically tested using eight image blocks collected with three UltraCamD digital large format photogrammetric cameras. Permanent photogrammetric test fields form the basis of the method. Important components of the method are determination of system parameters, evaluation of systematic errors, and assessment of geometric accuracy. The results showed that UltraCamD images contained systematic deformations that could not be modeled with single lens additional parameter models. Good point determination accuracy was obtained despite the systematic errors; the typical accuracy was 2–3 μm in image space in the horizontal coordinates and 0.05–0.09‰ of the object distance in height. One of the cameras had significantly poorer performance. In the worst cases, the horizontal accuracy was 5 μm in image space and the height accuracy was 0.18‰ of the object distance. The analog cameras gave better results than the UltraCamD, but the development of appropriate mathematical models for UltraCamD as well as improvements in digital sensors may change the situation in the near future.  相似文献   

14.
Zusammenfassung Nach dem Erdbeden von Nanka?do im Jahre 1946 hat man das Dreiecksnetz I. Ordnung in einem Gebiet von etwa 300 km Umkreis wiederbeobachtet, und zwar auf 47 Punkten insgeasamt 68 Winkel. Die letzte Triangulation fand in den Jahren 1885–96 statt.—Nach der Ausgleichung des Netzes wurden Punkverschiebungen bis zu 1,69 m festgestellt.
Resumen Después del temblor de tierra de 1946, en Nanka?do, se ha vuelto a observar la red de triangulación de 1H orden en un radio de 300 kilómetros aproximadamente. Los puntos de nuevo observados son 47 y los triángulos 68. La triangulaciín precedente se remontaba a los a?os 1885–96. Después de compensar la red, se han deducido los desplazamientos experimentados por los puntos sobre el terreno, que llegaron a ser de 1,69 metros.
Résumé Après le tremblement de tèrre de 1946 à Nankaido, on a réobservé le réseau de triangulation de premier ordre dans un rayon de 300 km environ. Les points réobservés sont au nombre de 47, et les triangles en nombre de 68. La triangtlation précédente remontait aux années 1885–96. La compensation du réseau effectuée, on en a déduit les déplacements subis par les points sur le terrain, qui importent jusqu’à 1,69 m.
Sommario Dopo il terremoto di Nankaido del 1946, è stata riosservata la rete di prim’ordine entro un raggio di circa 300 km. La precedente triangolazione risaliva agli anni 1885–96. Effettuata la compensazione, il confronto fra l’anticae la nuova triangolazione ha rivelato spostamenti nei vertici ammontanti fino a m 1,69.

Communication présentée à l’Assemblée Générale de Bruxelles en 1951  相似文献   

15.
Conclusions Le traitement des mesures Doppler sur des périodes voisines de 1 jour permet, par correction différentielle utilisant un bon modèle théorique, de retrouver les coordonnées,X, Y des stations du triangle méditerranéen avec des dispersions respectives de50 mètres et15 mètres. Bien que la coordonnéeZ soit moins bien déterminée, dispersion pouvant atteindre200 mètres, on peut retrouver les dimensions du triangle. L'analyse spectrale de la matrice de covariance fait appara?tre comme la plus grande composante de l'ellipso?de d'erreur, la cote du centre de gravité au-dessus du plan équatorial. Ceci peut s'expliquer par un manque de diversité des passages (période courte), un réseau d'observation trop restreint et dans le même hémisphère (mauvaise détermination dui), des imperfections du modèle de perturbations (Harmoniques de résonances, frottement). L'élimination des paramètres internes et la résolution, sur les seuls déplacements significatifs, diminue la dispersion à une dizaine de mètres surX, Y etZ. Ces résultats ne constituent qu'une première étape d'un traitement systématique en cours, qui sera exposé au COSPAR 1969.  相似文献   

16.
    
Conclusion Les travaux de nivellement effectués sur la Gironde ont done permis à l’Institut Géographique National de préciser ses idées sur des méthodes nouvelles. Il a pu constater, en particulier, qu’une méthode qu’il considère comme une méthode expédiée permet actuellement d’exécuter des nivellements qui valent ceux du réseau de 1er ordre, effectués par une méthode beaucoup plus longue et plus compliquée. Ces résultats sont dus pour une part à l’habileté technique des opérateurs. Ils sont dus aussi aussi à la qualité du matériel utilisé. Les perfectionnements apportés dans la construction des instruments. en particulier la précision des réalisations mécaniques actuelles, permet de s’affranchir d’un traditionnalisme devenu sans objet, et d’abandonner des modes opératoires, ingénieux certes et mathématiquement séduisants, qu’on avait imaginés pour pallier l’insuffisance des appareils. Confort dans les observations, économie de peine pour les opérateurs, gain de temps dans les travaux, augmentation de la précision dans les mesures, ce sont là des avantages sérieux qui concourent tous à l’amélioration de la qualité des résultats.   相似文献   

17.
A few of the many interesting aspects of the mind, life and work of Robert Hooke (1635-1703) are discussed, particularly some that are relevant to opto-mechanical photogrammetric plotters and cameras. Evidence from primary and secondary sources is presented which indicates that Hooke devised instruments with optical and mechanical components which later came to be used in photogrammetric plotters, that he recognized the value of perspective projection in accurate recording of terrain, and devised a "Picture-Box" for that purpose. The question of how far he progressed in photography in experiments with purple dyes is left open. These "photogrammetric" activities of Hooke's are shown to have been only a small part of his work in London which included duties as Curator of Experiments to the Royal Society, Professor of Geometry at Gresham College, and Surveyor to the City of London Authorities following the Great Fire in 1666.  相似文献   

18.
Devrim  Akca  Armin  Gruen 《The Photogrammetric Record》2009,24(127):217-245
This paper examines the potential of mobile phones to be used as front-end sensors for photogrammetric procedures and applications. For this purpose, two mobile phone cameras (Sony Ericsson K750i and Nokia N93) were calibrated over an indoor 3D testfield, using a self-calibrating bundle adjustment. Geometric accuracy tests were carried out in order to evaluate their metric performances and to compare the results with respect to two off-the-shelf digital still video cameras (Sony DSC W100 and Sony DSC F828). The geometric accuracy evaluation comprised an absolute accuracy test, JPEG test and temporal stability test. The radiometric capabilities of all cameras (except that the DSC W100 was replaced with a DSC T100 camera) were also evaluated and compared by carrying out modulation transfer function (MTF) analysis, image noise analysis and an operating range test. Substantial systematic errors were diagnosed in some systems. However, with proper calibration it is believed that these devices can be used for many photogrammetric tasks.  相似文献   

19.
Close-range photogrammetry is to determine the shape and size of the object, instead of it's absolute position. Therefore, at first, any translation and rotation of the photogrammetric model of the object caused by whole geodesic, photographic and photogrammetric procedures in close-range photogrammetry could not be considered. However, it is necessary to analyze all the reasons which cause the deformations of the shape and size and to present their corresponding theories and equations. This situation, of course, is very different from the conventional topophotogrammetry. In this paper some specific characters of limit errors in close-range photogrammetry are presented in detail, including limit errors for calibration of interior elements for close-range cameras, the limit errors of relative and absolute orientations in close-range cameras, the limit errors of relative and absolute orientations in close-range photogrammetric procedures, and the limit errors of control works in close-range photogrammetry. A theoretical equation of calibration accuracy for close-range camerais given. Relating to the three examples in this paper, their theoretical accuracy requirement of interior elements of camera change in the scope of ±(0.005–0.350) mm. This discussion permits us to reduce accuracy requirement in calibration for an object with small relief, but the camera platform is located in violent vibration environment. Another theoretical equation of relative RMS of base lines (mS/S) and the equation RMS of start direction are also presented. It is proved that themS/S could be equal to the relative RMS ofmΔX/ΔX. It is also proved that the permitting RMS of start direction is much bigger than the traditionally used one. Some useful equations of limit errors in close-range photogrammetry are presented as well. Suggestions mentioned above are perhaps beneficial for increasing efficiency, for reducing production cost.  相似文献   

20.
Résumé Dans cette étude on expose une adaptation de la méthode des directions —pour la compensation d’un réseau de triangulation—aux possibilités de l’ordinateur électronique. On présente les formules par lesquelles on calcule les coefficients des inconnues dans les équations de condition (équations aux angles et équations aux c?tés) et on dresse leur matrice. Ensuite on traite de la formation de la matrice des coefficients des équations normales et son inversion, qui fournit les quantités corrélatives de Lagrange. Enfin, après avoir déterminé les corrections à apporter aux directions observées, on calcule l’erreur moyenne quadratique d’une observation isolée et l’erreur moyenne de chacune des directions compensées.
Summary In this study, an adaptation to the computers’ possibilities, regarding the method of directions, is disclosed in order to realise the adjustment of triangulation nets. The computing formulae of the coefficients of the unknown quantities in the condition equations and the creation of their matrix are given herebelow. The treatment leading towards the construction of the matrix of normal equations and its inversion, that furnishes Lagrange’s quantities, follows. After the computation of the corrections applied on the observed directions, the mean error of a single observation and the mean error of every adjusted direction are determined. The study is executed in such a way that it can be included in only one programme for automatic computation.
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