2017 |
Hatzopoulos, John N; Stefanakis, Dimitrios; Georgopoulos, Andreas; Tapinaki, Sevasti; Pantelis, Volonakis; Liritzis, Ioannis In: Mediterr. Archaeol. Archaeom., vol. 17, no. 3, pp. 311–336, 2017, ISSN: 22418121. Abstract | Links | BibTeX | Tags: Education, Game engine, Laser scanner, Monument mapping, Photogrammetry, Restoration, Surveying, UAS @article{Hatzopoulos2017,This work was developed to train graduate students as part of the Delphi4Delphi project dealing with the digital reconstruction of the archaeological site of Delphi. In this part of the project, various technologies were used for 3-d digital mapping cultural heritage structures for maintenance and restoration purposes. The use of various surveying technologies such as UAS, Total station, digital camera, Lidar scanner and GPS to map in 3d the remaining of the monument Tholos and the surrounding area in Delphi Greece and based on such mapping to restore the entire structure is covered in detail. The remains of such monuments are a few columns standing up joined with original elements on top. In this part of the project GPS was used to establish the reference system, total station was used to measure a number of control points for UAS, close range photogrammetry and Lidar scanner, UAS was used to map precisely the surrounding area together with the structure, close range photogrammetry and Lidar scanner were used to map the vertical surfaces of the structure. Processing of above data from all surveying technologies created enough point cloud to map precisely the remains of the structure and expand their architectural design to precisely restore the entire Tholos monument. Also all digital data are used by software for the construction of 3D terrain and 3D models which when inserted into Game Engines software aim at the creation of educational scenarios. |
2016 |
Georgopoulos, A; Oikonomou, C; Adamopoulos, E; Stathopoulou, E K EVALUATING UNMANNED AERIAL PLATFORMS FOR CULTURAL HERITAGE LARGE SCALE MAPPING Journal Article In: ISPRS - Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci., vol. XLI-B5, pp. 355–362, 2016, ISSN: 2194-9034. Abstract | Links | BibTeX | Tags: dense matching, large scale mapping, orthophotos, structure from motion, UAS @article{Georgopoulos2016,When it comes to large scale mapping of limited areas especially for cultural heritage sites, things become critical. Optical and non-optical sensors are developed to such sizes and weights that can be lifted by such platforms, like e.g. LiDAR units. At the same time there is an increase in emphasis on solutions that enable users to get access to 3D information faster and cheaper. Considering the multitude of platforms, cameras and the advancement of algorithms in conjunction with the increase of available computing power this challenge should and indeed is further investigated. In this paper a short review of the UAS technologies today is attempted. A discussion follows as to their applicability and advantages, depending on their specifications, which vary immensely. The on-board cameras available are also compared and evaluated for large scale mapping. Furthermore a thorough analysis, review and experimentation with different software implementations of Structure from Motion and Multiple View Stereo algorithms, able to process such dense and mostly unordered sequence of digital images is also conducted and presented. As test data set, we use a rich optical and thermal data set from both fixed wing and multi-rotor platforms over an archaeological excavation with adverse height variations and using different cameras. Dense 3D point clouds, digital terrain models and orthophotos have been produced and evaluated for their radiometric as well as metric qualities. |
2017 |
In: Mediterr. Archaeol. Archaeom., vol. 17, no. 3, pp. 311–336, 2017, ISSN: 22418121. |
2016 |
EVALUATING UNMANNED AERIAL PLATFORMS FOR CULTURAL HERITAGE LARGE SCALE MAPPING Journal Article In: ISPRS - Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci., vol. XLI-B5, pp. 355–362, 2016, ISSN: 2194-9034. |