Articles by Alfonso Ippolito

Data acquisition digital methodologies have become a reliable tool for surveying buildings with heritage values. Laser scanning has become the preferred method for performing 3D digital surveys because of its high accurate results; even though, the cost associated with it is usually high. Emerging technologies have been able to produce low-cost data acquisition methods, and they are currently being incorporated as part of digital survey projects. Using the ‘Domus of the Calendar’ as a case study – an exceptionally unique archaeological and architectural site that was incorporated to the structural foundation system of the basilica of Santa Maria Maggiore – the present investigation aims to evaluate the data quality of two low-cost emerging technologies, namely SfM (Structure from Motion) and the iPad LiDAR system. This evaluation was developed by comparing low-cost technologies data acquisition capabilities with those of the laser scanner. The data for this test was obtained during an integrated survey campaign aimed at executing a critical analysis of the many historical layers of the Santa Maria Maggiore basilica. The results obtained from this investigation highlights the reliability of the different techniques implemented and suggest a useful solution for different and recurrent multi-scalar contexts.

In the past twenty years archaeological survey has changed radically thanks to the progress in the field of technology, in particular concerning 3D massive acquisition methods. A variety of data acquisition modes, based on active and passive sensor systems, is increasingly easier to access and use to document cultural heritage. The scientific debate focuses primarily on two issues: the use of free or proprietary software, and the control over data quality, in terms of metric accuracy, by comparing 3D image-based acquisition methods with consolidated methods (laser scansion and/or topographic survey). Collecting, interpreting and filing a large amount of information helps to define a system we can use to understand our archaeological heritage. The system is based on the scientific process used to achieve a dual objective: first, to document acquisition using a heterogeneous set of data (x, y, z and RGB) and metadata (information processing) and guarantee repeatability; secondly, to ensure data quality during acquisition and processing. Data processing obtained using 3D massive acquisition methods makes it possible to build models characterized by a biunivocal correspondence to the real object, studied from a geometric and spatial point of view. The study focuses on the shift from quantitative data, acquired in a semi-automatic manner, to qualitative data, meticulously controlled as regards to uncertainty. In this framework, all branches of the Science of Representation ensure metric, spatial and formal control of the built models. The study of the 13th century Gates of the city of Bologna have so far led to the development of a scientific process providing important data about metric quality vis-à-vis, the scale of the model.