Descripteur
Documents disponibles dans cette catégorie (451)
Ajouter le résultat dans votre panier
Visionner les documents numériques
Affiner la recherche Interroger des sources externes
Etendre la recherche sur niveau(x) vers le bas
Mapping with small UAS: A point cloud accuracy assessment / Charles K. Toth in Journal of applied geodesy, vol 9 n° 4 (December 2015)
[article]
Titre : Mapping with small UAS: A point cloud accuracy assessment Type de document : Article/Communication Auteurs : Charles K. Toth, Auteur ; Grzegorz Jóźków, Auteur ; Dorota A. Grejner-Brzezinska, Auteur Année de publication : 2015 Article en page(s) : pp 213 - 226 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] analyse comparative
[Termes IGN] caractérisation
[Termes IGN] drone
[Termes IGN] géoréférencement direct
[Termes IGN] image optique
[Termes IGN] qualité des données
[Termes IGN] semis de pointsRésumé : (auteur) Interest in using inexpensive Unmanned Aerial System (UAS) technology for topographic mapping has recently significantly increased. Small UAS platforms equipped with consumer grade cameras can easily acquire high-resolution aerial imagery allowing for dense point cloud generation, followed by surface model creation and orthophoto production. In contrast to conventional airborne mapping systems, UAS has limited ground coverage due to low flying height and limited flying time, yet it offers an attractive alternative to high performance airborne systems, as the cost of the sensors and platform, and the flight logistics, is relatively low. In addition, UAS is better suited for small area data acquisitions and to acquire data in difficult to access areas, such as urban canyons or densely built-up environments. The main question with respect to the use of UAS is whether the inexpensive consumer sensors installed in UAS platforms can provide the geospatial data quality comparable to that provided by conventional systems.
This study aims at the performance evaluation of the current practice of UAS-based topographic mapping by reviewing the practical aspects of sensor configuration, georeferencing and point cloud generation, including comparisons between sensor types and processing tools. The main objective is to provide accuracy characterization and practical information for selecting and using UAS solutions in general mapping applications. The analysis is based on statistical evaluation as well as visual examination of experimental data acquired by a Bergen octocopter with three different image sensor configurations, including a GoPro HERO3+ Black Edition, a Nikon D800 DSLR and a Velodyne HDL-32. In addition, georeferencing data of varying quality were acquired and evaluated. The optical imagery was processed by using three commercial point cloud generation tools. Comparing point clouds created by active and passive sensors by using different quality sensors, and finally, by different commercial software tools, provides essential information for the performance validation of UAS technology.Numéro de notice : A2015--010 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1515/jag-2015-0017 En ligne : http://dx.doi.org/10.1515/jag-2015-0017 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80762
in Journal of applied geodesy > vol 9 n° 4 (December 2015) . - pp 213 - 226[article]UAS Experiences in Africa / Marius Schrôder in GIM international, vol 29 n° 12 (December 2015)
[article]
Titre : UAS Experiences in Africa Type de document : Article/Communication Auteurs : Marius Schrôder, Auteur Année de publication : 2015 Article en page(s) : pp 21- 23 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Topographie moderne
[Termes IGN] Afrique équatoriale
[Termes IGN] Bénin
[Termes IGN] climat équatorial
[Termes IGN] conditions de travail
[Termes IGN] drone
[Termes IGN] instrument de géodésie
[Termes IGN] instrument de nivellement
[Termes IGN] savaneRésumé : (auteur) When conducting surveys in countries near the equator, environmental conditions can be harsh. Heat, dust and humidity may disrupt sensitive equipment, white distrustful locals may obstruct the undertaking. The author shares experiences of carrying out a UAS survey on the savannah of Benin, West Africa. Numéro de notice : A2015-830 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79129
in GIM international > vol 29 n° 12 (December 2015) . - pp 21- 23[article]Discrimination of deciduous tree species from time series of unmanned aerial system imagery / Jonathan Lisein in Plos one, vol 10 n° 11 (November 2015)
[article]
Titre : Discrimination of deciduous tree species from time series of unmanned aerial system imagery Type de document : Article/Communication Auteurs : Jonathan Lisein , Auteur ; Adrien Michez, Auteur ; Hugues Claessens, Auteur ; Philippe Lejeune, Auteur Année de publication : 2015 Article en page(s) : n° 0141006 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] analyse discriminante
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] drone
[Termes IGN] houppier
[Termes IGN] image aérienne
[Termes IGN] orthoimage
[Termes IGN] orthophotoplan numérique
[Termes IGN] phénologie
[Termes IGN] variation saisonnièreRésumé : (auteur) Technology advances can revolutionize Precision Forestry by providing accurate and fine forest information at tree level. This paper addresses the question of how and particularly when Unmanned Aerial System (UAS) should be used in order to efficiently discriminate deciduous tree species. The goal of this research is to determine when is the best time window to achieve an optimal species discrimination. A time series of high resolution UAS imagery was collected to cover the growing season from leaf flush to leaf fall. Full benefit was taken of the temporal resolution of UAS acquisition, one of the most promising features of small drones. The disparity in forest tree phenology is at the maximum during early spring and late autumn. But the phenology state that optimized the classification result is the one that minimizes the spectral variation within tree species groups and, at the same time, maximizes the phenologic differences between species. Sunlit tree crowns (5 deciduous species groups) were classified using a Random Forest approach for monotemporal, two-date and three-date combinations. The end of leaf flushing was the most efficient single-date time window. Multitemporal datasets definitely improve the overall classification accuracy. But single-date high resolution orthophotomosaics, acquired on optimal time-windows, result in a very good classification accuracy (overall out of bag error of 16%). Numéro de notice : A2015--031 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1371/journal.pone.0141006 En ligne : http://dx.doi.org/10.1371/journal.pone.0141006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81106
in Plos one > vol 10 n° 11 (November 2015) . - n° 0141006[article]UAV real-time: Data use in a lightweight direct georeferencing system / Christian Eling in GPS world, vol 26 n° 11 (November 2015)
[article]
Titre : UAV real-time: Data use in a lightweight direct georeferencing system Type de document : Article/Communication Auteurs : Christian Eling, Auteur ; Lasse Klingbeil, Auteur ; Markus Wieland, Auteur ; Erik Heinz, Auteur ; Heiner Kuhlmann, Auteur Année de publication : 2015 Article en page(s) : pp 44 - 55 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] drone
[Termes IGN] géoréférencement direct
[Termes IGN] GPS en mode cinématique
[Termes IGN] GPS-INS
[Termes IGN] magnétomètre
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] trajectographie par GPSRésumé : (auteur) Direct georeferencing with onboard sensors is less time-consuming for data processing than indirect georeferencing using ground control points, and can supply real-time navigation capability to a UAV. This is very useful for surveying, precision farming or infrastructure inspection. An onboard system for position and attitude determination of lightweight UAVs weighs 240 grams and produces position accuracies better than 5 centimeters and attitude accuracies better than 1 degree. Numéro de notice : A2015--087 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans En ligne : http://gpsworld.com/uav-real-time-data-use-in-a-lightweight-direct-georeferencin [...] Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84804
in GPS world > vol 26 n° 11 (November 2015) . - pp 44 - 55[article]Applying ASPRS accuracy standards to surveys from small unmanned aircraft systems (UAS) / Ken Whitehead in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 10 (October 2015)
[article]
Titre : Applying ASPRS accuracy standards to surveys from small unmanned aircraft systems (UAS) Type de document : Article/Communication Auteurs : Ken Whitehead, Auteur ; Chris H. Hugenholtz, Auteur Année de publication : 2015 Article en page(s) : pp 787 - 793 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] drone
[Termes IGN] modèle numérique de surface
[Termes IGN] norme de données localisées
[Termes IGN] orthoimage
[Termes IGN] point d'appui
[Termes IGN] précision des donnéesRésumé : (auteur) We present a first assessment of UAS-derived orthoimagery and digital elevation data in the context of newly-released accuracy standards for digital geospatial data developed by the American Society for Photogrammetry and Remote Sensing. We outline results from two case studies using a commercially-available UAS, photogrammetry software, and an array of ground control and check points. Radial horizontal and vertical root-meansquare- errors (RMSE) were calculated as 0.05 m and 0.06 m, respectively, for one site, and 0.08 m and 0.03 m, respectively, for the other. Under the 1990 ASPRS standards, both surveys meet the requirements for Class 1 accuracy at the 1:500 map scale and at the 0.50 m contour interval. Under the newly-developed ASPRS standards, the reported errors fulfill the requirements for both horizontal and vertical mapping at the 10 cm RMSE level. Overall, these results provide initial direction for practitioners considering UAS surveying in the context of accuracy standards Numéro de notice : A2015-989 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.81.10.787 En ligne : https://doi.org/10.14358/PERS.81.10.787 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80270
in Photogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 10 (October 2015) . - pp 787 - 793[article]Flying high with a UAS adventurer / Anonyme in Position, n° 79 (October - November 2015)PermalinkInstantaneous ambiguity resolution for URTK and its seamless transition with PPP-AR / Xuan Zou in GPS solutions, vol 19 n° 4 (october 2015)PermalinkLidar Scanning by Helicopter in the USA / Jeff Fagerman in GIM international, vol 29 n° 10 (October 2015)PermalinkRevealing a buried historic fort : archeology meets UAS technology / Andrea Sangster in Geoinformatics, vol 18 n° 7 (October - November 2015)PermalinkSurveying a mountain highway with UAS : getting accurate results in a rough area / Matteo Luccio in Geoinformatics, vol 18 n° 7 (October - November 2015)PermalinkAnalysis of different methods for 3D reconstruction of natural surfaces from parallel-axes UAV images / Annette Eltner in Photogrammetric record, vol 30 n° 151 (September - November 2015)PermalinkLe contrôle de la végétation dans les emprises ferroviaires : une approche multi-scalaire / Flavien Viguier in XYZ, n° 144 (septembre - novembre 2015)PermalinkGénération drones / Michel Ravelet in Géomètre, n° 2128 (septembre 2015)PermalinkA place in the sun / Krista Montgomery in GEO: Geoconnexion international, vol 14 n° 8 (September 2015)PermalinkPlanificateur de missions photogrammétriques pour drones ultra-légers (Micro Aerial Vehicle MAV) / F. Gandor in Géomatique suisse, vol 113 n° 9 (septembre 2015)PermalinkPrendre les espaces de temps pour maîtriser les impacts diffus générés par les grandes infrastructures de transport terrestre (ITT) sur la biodiversité / Jean-Marc Fourès in VertigO, vol 15 n° 2 (septembre 2015)PermalinkTélédétection pour l'agriculture de précision par caméra hyperspectrale miniature / D. Constantin in Géomatique suisse, vol 113 n° 9 (septembre 2015)PermalinkTrajectoires d’objets mobiles dans un espace support fixe / Elodie Buard in Revue internationale de géomatique, vol 25 n° 3 (septembre - novembre 2015)PermalinkWhere are we? (3) / Lewis Graham in GEO: Geoconnexion international, vol 14 n° 8 (September 2015)PermalinkWeb services for dynamic coloring of UAVSAR images / Jun Wang in Pure and applied geophysics, vol 172 n° 8 (August 2015)PermalinkDetection of high speed railway track static regularity with laser trackers / L. Yao in Survey review, vol 47 n° 343 (July 2015)PermalinkSeeing the light: a vision-aided integrity for precision relative navigation systems / Sean Calhoun in GPS world, vol 26 n° 7 (July 2015)PermalinkCastles in the sky / Krista Montgomery in GEO: Geoconnexion international, vol 14 n° 6 (June 2015)PermalinkenviroCar: A citizen science platform for analyzing and mapping crowd-sourced car sensor data / Arne Bröring in Transactions in GIS, vol 19 n° 3 (June 2015)PermalinkPermalink