Proceedings of the Second International Conference on Railway Technology: Research, Development and Maintenance
ABSTRACT In recent years unmanned vehicle (UV) systems became relevant for applications in precis... more ABSTRACT In recent years unmanned vehicle (UV) systems became relevant for applications in precision farming and in infrastructures maintenance such as road maintenance and dam surveillance. The name unmanned aerial vehicle (UAV) includes all vehicles, which are flying in the air with no person onboard with the capability of controlling the aircraft. This term is used commonly in the computer science and artificial intelligence community, but terms such as remotely piloted vehicle (RPV), remotely operated aircraft (ROA), remote controlled helicopter (RC-Helicopter), unmanned vehicle systems (UVS) and model helicopter are often used. The remote and model helicopters are clearly defined by the Unmanned Vehicle Systems International Association as mini, close, short and medium range UAVs depending on their size, endurance, range and flying altitude. These innovative developments have not been deeply investigated for railway domain or energy transport but have been identified as a key factor for reducing maintenance costs. The UAV platforms are nowadays a valuable source of data for inspection, surveillance, mapping and three-dimensional modelling issues.
RESUME : Depuis 2007, le groupe PAGE (Photogrammetrie Architecturale et GEomatique) intervient su... more RESUME : Depuis 2007, le groupe PAGE (Photogrammetrie Architecturale et GEomatique) intervient sur le site dans le cadre d’un Projet Collectif de Recherches. L’ensemble des donnees acquises depuis 3 ans vise a la sauvegarde numerique du site via la construction de modeles tridimensionnels servant de support a l’expertise archeologique. La realisation de ces modeles necessite la combinaison de donnees lasergrammetriques et photogrammetriques. L’utilisation de la technique de Correlation Epipolaire Dense (CED) nous permet ainsi de generer des nuages de points 3D a partir d’images 2D et ainsi de completer le nuage lasergrammetrique. En veillant a la coherence geometrique de l’ensemble, nous construisons ensuite le modele surfacique maille representant le theâtre dans son etat actuel. Avec l’appui d’expertises architecturales et archeologiques conjointes, nous pouvons alors proposer une restitution tridimensionnelle du theâtre dans son etat antique. Des images de synthese sont alors creees a des fins de communication, notamment pour le grand public. //////////////////////////////////////////////////////////// TRADUCTION : Since 2007, the group PAGE (Architectural Photogrammetry and Geomatics) operates on the site as part of a Collective Research Project. All data acquired for three years aimed at digital preservation of the site via the construction of three-dimensional models for supporting archaeological expertise. The realization of these models requires a combination of photogrammetric and lasergrammetric data. Using the technique of Dense Stereo Matching (DStM) allows us to generate 3D point clouds from 2D images and thus complement the lasergrammetric cloud. By ensuring geometrical consistency, we construct the mesh surface model representing the theater in its current state. With the joint support of architectural and archaeological expert, we propose a three-dimensional restitution of the antic theater. Synthesized images are then created at ends of communication, particularly for a large public.
ABSTRACT In order to increase its knowledge of rock slope stability along the French national rai... more ABSTRACT In order to increase its knowledge of rock slope stability along the French national rail network, the SNCF Engineering Management is developing a new approach for sampling and modeling rock discontinuities. The rock face diagnosis is a follow-up and check operation of the field works. This operation allowed to optimize the rock risk treatment at the best price in respect with safety requirements. These operations require the measurement of orientation and location of rock discontinuities at the surface of the rock mass and is followed by a structural modeling in order to extrapolate the data collected at the surface to the inner part of the massif. At present, this work is completed manually with a compass-clinometer, in a simplified way mainly based on the specialist's experience. The analysis remains empirical, and most of the time restricted to the most fractured zone, whereas safety requirements ask for an exhaustive study on the whole of the site. Filling these gaps, the combined use of dense three-dimensional measurement techniques, associating both terrestrial laser scanning and optical imaging, makes it possible to obtain a more complete structural statement. The data acquisition and processing need protocols adapted to the railway environment for obtaining suitable 3D models. Then the exploitation of these models requires the development of semi-automatic process, with an aim of, to support the geologist's on-site expertise with a digital model exploitation. The geometrical characterization of the rock mass is undertaken thanks to a classification of the model in several subsets corresponding to the main directional families. The data on these planar discontinuities, traditionally acquired manually in certain points necessarily accessible of the rock face, result now from dense 3D models covering the whole of the work. Therefore, statistical sampling is stronger, while the time of the on-site survey is reduced. By these means, the diagnosis should be made reliable and the recommendations optimized with the unfavourable sectors. Then, risk analysis can be targeted on the potential disorders zones and not on the whole of the studied sector. Keywords : Discontinuities, fractures, railway exploitation, terrestrial laser-scanner, dense image matching, rock mass characterization, directional families, data processing
Proceedings of SPIE - The International Society for Optical Engineering, 2011
Several recording techniques are used together in Cultural Heritage Documentation projects. The m... more Several recording techniques are used together in Cultural Heritage Documentation projects. The main purpose of the documentation and conservation works is usually to generate geometric and photorealistic 3D models for both accurate reconstruction and visualization purposes. The recording approach discussed in this paper is based on the combination of photogrammetric dense matching and Terrestrial Laser Scanning (TLS) techniques. Both techniques
In this paper, we present a methodology for Dense Stereo Matching (DStM) acquisition and processi... more In this paper, we present a methodology for Dense Stereo Matching (DStM) acquisition and processing. Two main applications are detailed. In our application sites, many constraints led us to choose DStM. In the archaeological site of the Gallo-Roman Theatre of Mandeure (France), a initial terrestrial laser scanning campaign had to be completed with patches acquired from DStM because of the site geometric complexity. In the epigraphic and archaeological site of the region of Kilwa (Saudi Arabia), we applied DStM for both prospecting and excavating. We distinguished two kinds of applications in the paper: 1 to 5 stereopairs and 5 to 30 stereopairs. We inserted the data of both kind of cases into larger datasets. These datasets are currently used for archaeological reconstruction purposes of as-built buildings.
Proceedings of the Second International Conference on Railway Technology: Research, Development and Maintenance, 2014
ABSTRACT In recent years unmanned vehicle (UV) systems became relevant for applications in precis... more ABSTRACT In recent years unmanned vehicle (UV) systems became relevant for applications in precision farming and in infrastructures maintenance such as road maintenance and dam surveillance. The name unmanned aerial vehicle (UAV) includes all vehicles, which are flying in the air with no person onboard with the capability of controlling the aircraft. This term is used commonly in the computer science and artificial intelligence community, but terms such as remotely piloted vehicle (RPV), remotely operated aircraft (ROA), remote controlled helicopter (RC-Helicopter), unmanned vehicle systems (UVS) and model helicopter are often used. The remote and model helicopters are clearly defined by the Unmanned Vehicle Systems International Association as mini, close, short and medium range UAVs depending on their size, endurance, range and flying altitude. These innovative developments have not been deeply investigated for railway domain or energy transport but have been identified as a key factor for reducing maintenance costs. The UAV platforms are nowadays a valuable source of data for inspection, surveillance, mapping and three-dimensional modelling issues.
Proceedings of the Second International Conference on Railway Technology: Research, Development and Maintenance
ABSTRACT In recent years unmanned vehicle (UV) systems became relevant for applications in precis... more ABSTRACT In recent years unmanned vehicle (UV) systems became relevant for applications in precision farming and in infrastructures maintenance such as road maintenance and dam surveillance. The name unmanned aerial vehicle (UAV) includes all vehicles, which are flying in the air with no person onboard with the capability of controlling the aircraft. This term is used commonly in the computer science and artificial intelligence community, but terms such as remotely piloted vehicle (RPV), remotely operated aircraft (ROA), remote controlled helicopter (RC-Helicopter), unmanned vehicle systems (UVS) and model helicopter are often used. The remote and model helicopters are clearly defined by the Unmanned Vehicle Systems International Association as mini, close, short and medium range UAVs depending on their size, endurance, range and flying altitude. These innovative developments have not been deeply investigated for railway domain or energy transport but have been identified as a key factor for reducing maintenance costs. The UAV platforms are nowadays a valuable source of data for inspection, surveillance, mapping and three-dimensional modelling issues.
RESUME : Depuis 2007, le groupe PAGE (Photogrammetrie Architecturale et GEomatique) intervient su... more RESUME : Depuis 2007, le groupe PAGE (Photogrammetrie Architecturale et GEomatique) intervient sur le site dans le cadre d’un Projet Collectif de Recherches. L’ensemble des donnees acquises depuis 3 ans vise a la sauvegarde numerique du site via la construction de modeles tridimensionnels servant de support a l’expertise archeologique. La realisation de ces modeles necessite la combinaison de donnees lasergrammetriques et photogrammetriques. L’utilisation de la technique de Correlation Epipolaire Dense (CED) nous permet ainsi de generer des nuages de points 3D a partir d’images 2D et ainsi de completer le nuage lasergrammetrique. En veillant a la coherence geometrique de l’ensemble, nous construisons ensuite le modele surfacique maille representant le theâtre dans son etat actuel. Avec l’appui d’expertises architecturales et archeologiques conjointes, nous pouvons alors proposer une restitution tridimensionnelle du theâtre dans son etat antique. Des images de synthese sont alors creees a des fins de communication, notamment pour le grand public. //////////////////////////////////////////////////////////// TRADUCTION : Since 2007, the group PAGE (Architectural Photogrammetry and Geomatics) operates on the site as part of a Collective Research Project. All data acquired for three years aimed at digital preservation of the site via the construction of three-dimensional models for supporting archaeological expertise. The realization of these models requires a combination of photogrammetric and lasergrammetric data. Using the technique of Dense Stereo Matching (DStM) allows us to generate 3D point clouds from 2D images and thus complement the lasergrammetric cloud. By ensuring geometrical consistency, we construct the mesh surface model representing the theater in its current state. With the joint support of architectural and archaeological expert, we propose a three-dimensional restitution of the antic theater. Synthesized images are then created at ends of communication, particularly for a large public.
ABSTRACT In order to increase its knowledge of rock slope stability along the French national rai... more ABSTRACT In order to increase its knowledge of rock slope stability along the French national rail network, the SNCF Engineering Management is developing a new approach for sampling and modeling rock discontinuities. The rock face diagnosis is a follow-up and check operation of the field works. This operation allowed to optimize the rock risk treatment at the best price in respect with safety requirements. These operations require the measurement of orientation and location of rock discontinuities at the surface of the rock mass and is followed by a structural modeling in order to extrapolate the data collected at the surface to the inner part of the massif. At present, this work is completed manually with a compass-clinometer, in a simplified way mainly based on the specialist's experience. The analysis remains empirical, and most of the time restricted to the most fractured zone, whereas safety requirements ask for an exhaustive study on the whole of the site. Filling these gaps, the combined use of dense three-dimensional measurement techniques, associating both terrestrial laser scanning and optical imaging, makes it possible to obtain a more complete structural statement. The data acquisition and processing need protocols adapted to the railway environment for obtaining suitable 3D models. Then the exploitation of these models requires the development of semi-automatic process, with an aim of, to support the geologist's on-site expertise with a digital model exploitation. The geometrical characterization of the rock mass is undertaken thanks to a classification of the model in several subsets corresponding to the main directional families. The data on these planar discontinuities, traditionally acquired manually in certain points necessarily accessible of the rock face, result now from dense 3D models covering the whole of the work. Therefore, statistical sampling is stronger, while the time of the on-site survey is reduced. By these means, the diagnosis should be made reliable and the recommendations optimized with the unfavourable sectors. Then, risk analysis can be targeted on the potential disorders zones and not on the whole of the studied sector. Keywords : Discontinuities, fractures, railway exploitation, terrestrial laser-scanner, dense image matching, rock mass characterization, directional families, data processing
Proceedings of SPIE - The International Society for Optical Engineering, 2011
Several recording techniques are used together in Cultural Heritage Documentation projects. The m... more Several recording techniques are used together in Cultural Heritage Documentation projects. The main purpose of the documentation and conservation works is usually to generate geometric and photorealistic 3D models for both accurate reconstruction and visualization purposes. The recording approach discussed in this paper is based on the combination of photogrammetric dense matching and Terrestrial Laser Scanning (TLS) techniques. Both techniques
In this paper, we present a methodology for Dense Stereo Matching (DStM) acquisition and processi... more In this paper, we present a methodology for Dense Stereo Matching (DStM) acquisition and processing. Two main applications are detailed. In our application sites, many constraints led us to choose DStM. In the archaeological site of the Gallo-Roman Theatre of Mandeure (France), a initial terrestrial laser scanning campaign had to be completed with patches acquired from DStM because of the site geometric complexity. In the epigraphic and archaeological site of the region of Kilwa (Saudi Arabia), we applied DStM for both prospecting and excavating. We distinguished two kinds of applications in the paper: 1 to 5 stereopairs and 5 to 30 stereopairs. We inserted the data of both kind of cases into larger datasets. These datasets are currently used for archaeological reconstruction purposes of as-built buildings.
Proceedings of the Second International Conference on Railway Technology: Research, Development and Maintenance, 2014
ABSTRACT In recent years unmanned vehicle (UV) systems became relevant for applications in precis... more ABSTRACT In recent years unmanned vehicle (UV) systems became relevant for applications in precision farming and in infrastructures maintenance such as road maintenance and dam surveillance. The name unmanned aerial vehicle (UAV) includes all vehicles, which are flying in the air with no person onboard with the capability of controlling the aircraft. This term is used commonly in the computer science and artificial intelligence community, but terms such as remotely piloted vehicle (RPV), remotely operated aircraft (ROA), remote controlled helicopter (RC-Helicopter), unmanned vehicle systems (UVS) and model helicopter are often used. The remote and model helicopters are clearly defined by the Unmanned Vehicle Systems International Association as mini, close, short and medium range UAVs depending on their size, endurance, range and flying altitude. These innovative developments have not been deeply investigated for railway domain or energy transport but have been identified as a key factor for reducing maintenance costs. The UAV platforms are nowadays a valuable source of data for inspection, surveillance, mapping and three-dimensional modelling issues.
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Papers by P. Assali