Knowing the past for managing the present: A comparison between historical cartography and satellite images for the study of Rome's city centre

The idea of this paper, develops from the consideration that, since the second half of the XXth century, urban planning of Italian historical centers seems constrained by the fear of compromising the architectures of the past. Rome's city centre, today UNESCO site, gathers a built up heritage that witness its long and unique existence. The missing industrialization phase that, during the XIXth century, determined the urban transformation of the great European capital cities, has permitted to a large area characterized by highly stratified urban tissue to survive. The aim of this project is to exploit the geometric precision and descriptive detail, characterizing the "Nuova pianta di Roma", published in 1748 by Giovanni Battista Nolli, fot studying the urban transformations at housing block level. The rigorous georeferencing of the historical cartography, allows for the spatial comparison with actual cartographies and with very high resolution satellite images, and the consequent analysis of the urban structure and its formal and functional contents

Historic cartography of L'Aquila city as a support to the study of earthquake damaged buildings

The city-center of L'Aquila suffered big damages from the main seismic event (6th April 2009, 3:32 a.m., local time; Ml=5.8, Mw= 6.2) of the seismic sequence that included hundreds of aftershocks (more than 30 of them 3.5<5.0) (INGV, 2009). Causes and modality of the collapse of some buildings are still under investigation. A 1:2000 map representing the center of L'Aquila city at the beginning of twentieth century was recently found and the comparison of this map with contemporary ones can help the study of the causes of the different response to seismic stress to different aged buildings. This study represents the first step to build a database of historic buildings in L'Aquila to test a potential correlation between the anti-earthquake regulations adopted over the years and the resulting damages. A comparison with post earthquakes damage map and the map of seismic zoning was performer to find all the possible combination of other parameters that together with building age can help to evaluate building vulnerability

Development of a software to plan UAVs stereoscopic flight: An application on post earthquake scenario in L'Aquila city

On April 6, 2009, an earthquake hit the historic center of L'Aquila city, hundreds of victims, thousands of collapses. During the post-emergency a continuous monitoring of all building is crucial in order to guarantee that each structure at least will not worsen its stability until the final reconstruction is completed. So detailed surveying of all building is performed using different geomatic techniques as total stations, land photogrammetry, and laser scanners. Even if all these techniques can perfectly respond to many crucial post hazard needs, there are still many monitoring that cannot be completely carried on with traditional techniques. For these reasons, in this work, the advantages of using multirotor UAVs will be illustrated; UAVs can be fully remote controlled and so the geometry of photogrammetric image acquisition can be imposed. For this task planning of flight is essential so a package was realized to obtain actual photogrammetric stereoscopic acquisitions. © 2013 Springer-Verlag Berlin Heidelberg

development of a software to optimize and plan the acquisitions from uav and a first application in a post seismic environment

AbstractAn Unmanned Aerial Vehicle (UAV) is an aircraft without a human pilot on board. UAVs allow close-range photogrammetric acquisitions potentially useful for building large-scale cartography and acquisitions of building geometry. This is particularly useful in emergency situations where major accessibility problems limit the possibility of using conventional surveys. Presently, however, flights of this class of UAV are planned based only on the pilot's experience and they often acquire three or more times the number of images needed. This is clearly a time-consuming and autonomy-reducing procedure, which is certainly detrimental when extensive surveys are needed. For this reason new software, to plan the UAV's survey will be illustrated

Automatic three-dimensional features extraction: The case study of L'Aquila for collapse identification after April 06, 2009 earthquake

This paper illustrates an innovative methodology for post-earthquake collapsed building recognition, based on satellite-image classification methodologies and height variation information. Together, the techniques create a robust classification that seems to yield good results in this application field. In the first part of this study, two different feature extraction methodologies were compared, based respectively on pixel-based and object-oriented approaches. Then the classification results of the most accurate classification methodology, obtained on an eight band WorldView-2 monoscopic image, were completed with height variation information before and after the event. The height difference is calculated, comparing a photogrammetric DSM, obtained using a photogrammetric rigorous orbital model on some EROS-B 0.7 metre across-track stereopairs with a 'roof model' before the earthquake

Unmanned aerial vehicle for post seismic and other hazard scenarios

On April 6, 2009, an earthquake hits the old city of L’Aquila resulting in hundreds of victims and thousands of collapses. The post emergency and very crucial phase regarding surveys, structure controls and investigations till now is fully underway. Conventional surveying techniques using high precision total stations, GNSS and laser scanners, are instruments of extreme operability but here are still many evident limits on their use especially regarding the survey of both the roofs and the facades of tall buildings or dangerous places, typical in post earthquake situations. Another very important disadvantage of the traditional surveying, especially during the post seismic periods, regards the overall safety of the instruments, operators and workers. In particular, the seismic sequence that may last for months after the main shock, causing collapses and ulterior damage that in most cases can also damage the transport and communication infrastructure creating important problems for all instruments located in that area and definitely posing a further serious risk for all operators. Moreover, some surveys have to be repeated periodically in order to achieve a final result. On the other hand, by using micro UAVs (Unmanned Aerial Vehicles) for surveying in such particular scenarios, many of these problems can easily bypassed. For example, there are no accessibility problems for an UAV mainly because of its extreme flying capabilities that can really permit the access of virtually any place. Regarding the security, these instruments are fully remotely controlled, so they do not involve any risk for the operators simply because they are in the dangerous area. For these reasons, in this work, we’ll explain the advantages of multirotor UAVs, fully remotely controlled, to acquire roofs and facades of structures in an old city center damaged by a seismic sequence like L’Aquila city

Prism triplet and stereopairs to build digital surface models

In the present paper the phases of extraction of a DSM from Prism stereopairs and triplets are illustrated. PRISM was a panchromatic radiometer carried onboard the Japanese remote sensing satellite ALOS (Advanced Land Observing Satellite); this work has mainly a methodological value cause on May 12, 2011, a command was sent to stop the onboard transmitter and now the sensor is no more operative. The sensor had three optical systems for forward, nadir and backward views with 2.5 meter nominal spatial resolution. Multiple Linear Array CCD chips were located on the focal plane of each camera, along one across-track line. Images here studied represent a coastal area that spans from the city of Pescara to the city of Ortona (both in Abruzzo region, Italy). The availability of PRISM stereopairs and triplets is not widely studied and in this paper accuracy of produced DEMs is compared with heights from terrestrial Lidar survey on the area of the city of Pescara (Abruzzo region, Italy). Extraction was executed with Geomatica 2012 using rigorous model, with GCPs