Corso, J.M.; Muñoz, F.; Garcia-Almirall, Pilar; Gracia, C.; Casals, J.; Martinez, J. Congreso Iberoamericano de Geomática y Ciencias de la Tierra p. 183-195 Data de presentació: 2016-10-26 Presentació treball a congrés
For maintenance needs, conservation and restoration, it has been requested by the Board of the SagradaFamilia, the study of the methodology and development to carry out the full three-dimensional model of the original part of the temple (the façade of the Birth, and the adjacent towers and chapels) and metric documents, including those who have to emphasize the architectonics planes, the digital orthomosaic of the different planes, and a full high-resolution surface model. The uniqueness of this façade is that it is an about 12 meters thick irregular element with spaces inside, which can be walked across most its outside spaces and inside the towers at different levels.
High accuracy surveying methods are used for this project, which must be used as a basis to generate the necessary support network, considering that the topographic bases must be placed throughout all the façade, inside the temple, at different levels and in positions with good visibility.In the methodology they are considered combined methods of laser scanning and high resolution photogrammetry, which can generate equivalent and complementary point clouds.The areas that the laser scanner can’t reach, photogrammetry is used, and vice versa.Job success is due to a good coordination and planning of the various phases to execute (photographic shots, Terrestrial Laser Scanning, topographic bases distribution and support points, etc).
This project is currently being carried out and the first results have been obtainedwholly satisfactory and above the highest expectations. The results have been point clouds of 2mm resolution for the sculptures and 5mm resolution for the architectural set made with the Terrestrial Laser Scanning technology, 5mm orthophotos with fotogrametry and a 3D mesh.
Orthophotograph, orthoimages or orthophotomaps have become common and fundamental documents for urban planning, civil engineering projects, etc., by themselves or as a complement of geographic information systems. The success of these products, as opposed to topographic maps, lies in their facility in locating zones and buildings. This paper presents several digital elevation models (DEMs) obtained by photogrammetric correlation and shuttle radar topography mission (SRTM) models. Not only is the potential application of SRTM models analysed, but also their direct use and support to photogrammetric correlation. This process has been applied to several zones that differ in topography: plain, undulating, mountainous. As a result of the analysis, these models showed themselves to be useful in obtaining orthophotomaps accurate enough to work at medium to small scale in mapping, engineering projects, etc. They save time and money in the map production process and they are mainly used in engineering works and projects in developing areas that do not have any more accurate digital terrain model (DTM) available or the means to obtain them. Valid scales are analysed for each type of terrain. Likewise, DTMs would be very useful to obtain not only orthophotograph, but also rectified photographs in global applications for free distribution. A cost reduction study is also presented when these models are used as part of the digital photogrammetric process to obtain orthophotomaps.