See discussions, stats, and author profiles for this publication at: http://www.researchgate.net/publication/261711358 The Diagnosis of The Royal Tobacco Factory of Seville assisted by Quad-rotor Helicopters CONFERENCE PAPER · JANUARY 2013 DOWNLOADS VIEWS 97 58 7 AUTHORS, INCLUDING: Pilar Ortiz María Auxiliadora Vázquez Universidad Pablo de Olavide Universidad de Sevilla 28 PUBLICATIONS 45 CITATIONS 18 PUBLICATIONS 38 CITATIONS SEE PROFILE SEE PROFILE José M Martín Ramírez Patricia Aparicio Universidad Pablo de Olavide Universidad de Sevilla 17 PUBLICATIONS 33 CITATIONS 63 PUBLICATIONS 221 CITATIONS SEE PROFILE SEE PROFILE Available from: Patricia Aparicio Retrieved on: 24 July 2015 The Diagnosis of The Royal Tobacco Factory of Seville assisted by Quad-rotor Helicopters. Pilar Ortiz1, Francisco Javier Ortega2, Mª Auxiliadora Vázquez2, José María Martín1, Patricia Aparicio2, Joaquín Ferruz3, Fernando Caballero, Iván Maza, Aníbal Ollero3 1University of Pablo de Olavide, Department of Physical, Chemical and Biological Systems, Utrera Road, km 1, Seville, Spain, e-mail: [email protected] 2University of Seville, Department of Crystallography, Mineralogy and Agricultural Chemist, Seville, C/Profesor García González, S/N, Spain 3Robotics, Vision and Control Group, University of Seville, Avd. De los Descubrimientos s/n, 41092, Sevilla, Spain; E-Mail: [email protected], [email protected], [email protected] ABSTRACT This paper describes the application of small Unmanned Aerial Vehicles (UAVs), specifically quad-rotor helicopters, to the weathering analysis of external building walls. The demonstrations have been carried out in the Main Building of the University of Seville. This Monument built in 18th-century as the Royal Tobacco Factory was restructured to allocate the University of Seville in 1950s. The digital images and infrared records carried out by the UAVs have been contrasted with the weathering maps and infrared data taken on-site. The results show in both cases that the main weathering forms are loss of materials, fissures, fractures and chromatic alterations. The quality of images taken from the UAVs does not allow a clear quantification of damages, but it is a useful tool during the work on-site. Temperatures differences have been detected on cornices with the UAVs according to the IR records. Traditional façade analysis and monitoring of historical buildings usually requires a time-consuming activity, including sometimes setting up auxiliary scaffolding to provide accessibility to the target areas. The application of UAVs to this kind of activities would drastically reduce the time devoted to deployment, because the optimal height and distance from the wall can be reached without the need of auxiliary support structures. In addition, UAVs can cover the target area in a very short time and a safer way, because no direct handling of the sensors is required. Nevertheless, it would be valuable to increase the stability and the quality of images so it could be possible to carry out digital image analysis to quantify damages from the photo-mosaics developed by UAVs. INTRODUCTION The Royal Tobacco Factory of Seville was built in XVIII century, with a clearly industrial architecture designs due to the work of civil and military architects and engineering as Ignacio Salas, Diego Bordick Deverez, Sebastián Van der Bosch and Vicente Acero. This Monument is the largest and most architecturally distinguished building of this type in Spain, and one of the oldest in Europe. Renaissance architecture provides the main points of reference, with Herrerian influences in its floor plan, courtyards, and the details of the façades. There are also motifs reminiscent of architects Sebastiano Serlio and Palladio. The stone façades are modulated by pilasters on pedestals. The tobacco factory began production in 1978 and in 1950 it was decided to move the tobacco operations to the Remedios neighbourhood and to use the historic building as headquarters of the University of Seville. The transformation of the building was a major undertaking, performed between 1954 and 1956 according with the plans of the architect Toro Buiza, the final aim was to host the faculties of law, science, phylosophy, and the administration and library of the University. The building occupies a huge rectangle of 185 x 147 meters that was an ancient roman cemetery out of the city (figure 1). Figure 1. General view of the Royal Tobacco Factory. Image of University of Seville. In 2010, a restoration of the Facades was started by the Architect Miguel González Vílchez, for this purpose, a diagnosis of the conservation degree of every façade was scheduled. The use of robots to help the inspections and diagnosis has been analysed due to the huge dimensions of this building. With this purpose, two different projects have collaborated to perform the studies, ROBAIR, about Reliability and Safety in Aerial Robotics, financed by the Spanish government, and RIVUPH, about Risk and Vulnerability of regional Monuments, financed by the Andalusia Government. Different kinds of robots have began to be applied in Cultural Heritage protection for diferents aims in the last decades. Special mention need those use for documenting and presenting artefacts (Antlej at al., 2011), for diagnosis in underwater archeology for the inspection of seabed (Drap et al., 2011), for the restoration and maintenance (Ceccarelli & Cigola, 2008), for the study of historical and archaeological sites (Cicirelli and Milella 2008). Other key applications of robots in Cultural Heritage are based on inspection after earthquake (Kruijff et al., 2012) or analytical evaluation of paintings based mainly on laser (Fiorani et al., 2010) or x-ray sources (Hocquet et al, 2011). UAVs have been employed for visual surveillance of Cultural Heritage Sites, specially in archeological studyes (Leo et al., 2005, Eisenbeiss & Zhang, 2006, Skarlatos et al., 2006). In these cases, relevant requirements for the UAV are hovering flight capability, minimum payload and safety with respect to persons and Cultural Heritage Buildings or remains. Single or multiple-rotor helicopter can be used for these purpose; small quad- rotor models are particularly attractive because of the simplicity and reliability of their mechanics. They can be programmed to execute autonomously inspections and can be also handled under manual control. METHODOOGY The study of the weathering forms has been carried out by means of the visual inspection. These macroscopic pathologies have been described by the terminology of NORMAL regulation 1/88 (1988), Ordaz and Esbert (1988), Martin (1990), Fitzner et al. (1992 & 1995) and the glossary of ICOMOS-ISCS (2008). The weathering maps have been built by AutoCAD LT 2008. For this work, two areas of the façades (figure 2) have been analysed in order to evaluate the UAV-based inspection applied to historical buildings. 100 m B A Figure 2. Zones of analysisA by UAVs in the Royal Tobacco Factory. A) Palos de la Frontera Façade, B) María de Padilla Façade. The UAV-based methodology allows us to record videos at different heights along the wall and to carry out an infrared inspection simultaneously. At the same time, a punctual thermo-graphic analysis was carried out by a IR camera BARNES model INSTATHERM to measure the temperature at selected eight spots on the each analysed facades. For UAV-based inspection a commercial Pelican VI quad-rotor platform from Ascending Technologies has been used (figure 3). The robot has a payload limit of 500 g, automatic attitude stabilization capability and optional automatic position control functions. A visual Canon IXUS i130 camera and an Raytheon 2500 AS infrared camera have been installed over the quad-rotor. A Sensoray 2253 board has been employed for digitalization and mp4 compression. Figure 3. Quad-rotor platform Pelican VI from Ascending Technologies used during the diagnosis of weathering degree. RESULTS The on-site analysis by nondestructive technique of weathered surfaces and the lythotypes have allowed to point out that the main weathering forms are the losses of materials (figure 4a), fissures and fractures in the balustrades and cornices (figure 4b) and chromatic alteration in blocks at different heights (figure 4c). The crusts and deposits are concentrated in the protected areas under cornices (figure 4d). Figure 4. Materials and weathering forms in The Royal Fabrica of Tobacco (Seville). a) Calcarenite with loss of materials. b) Calcarenites with fissures and fractures, c) Calcarenites with Crromaric alteration d) Calcarenites with black crust and deposits. Other widely spread out damages are alveolization, erosion and differential weathering. The encrustations of repair mortars from different restorations are detected all over the walls. Figures 5 show the photo mosaic of the visible images taken by UAV on the Façade of Palos de la Frontera of the Royal Tobacco Factory and the weathering map built with AutoCAD after the on-site visual analysis in the same façade. The quality of the UAV’s images do not allow a digital image analysis to quantify the wathering forms extension and degree according to the methodology developed by Vazquez el al. (2011), due to dpi and photomontage quality. a) b) Cracks and Fractures Blistering Disintegration Missing part Discolouration Crust Impact damage Alveolization Figure 5. a) Photo mosaic of the visible images taken by UAV on the Façade of Palos de la Frontera of the Royal Tobacco Factory. b) Weathering map carried out by AutoCAD with the in-situ visual analysis in the same Facade. The temperature measurements on the wall at this time show a range between 8-11ºC on the Façade of Palos de la Frontera; it decreases to 6-8ºC in the Façade B (Maria Padilla Street) as this façade is facing North and is surrounded by trees, so the differences along the day are smaller. Some temperature differences can be observed by the UAV equipment in the areas of the cornices and basements on both zones of analysis (figure 6). This photo mosaic carried out with the infrared images can not allow developing ulterior analysis and quantifications, due to the quality of the images and overlapping.