Assessments for 3d Reconstructions of Cultural Heritage Using Digital Technologies

Abstract

ABSTRACT:The aim of this contribution is to show the results of evaluations on 3D digitizations performed using different methodologies and technologies. In particular, for surveys conducted at the architectural and urban scale, the recent reduction of costs related to Time of Flight and phase shift laser scanners is actually enhancing the replacement of traditional topographic instruments (i.e. total stations) with range-based technologies for the acquisition of 3D data related to built heritage. If compared to surveys performed using traditional topographic technologies, range-based ones offer a wide range of advantages, but they also require different skills, procedures and times. The present contribution shows the results of a practical application of both approaches on the same case study. Another application was suggested by the recent developments in the photogrammetric field that enhance the improvement of software able to automatically orient uncalibrated cameras and derive dense and accurate 3D point clouds, with evident benefits in reduction of costs required for survey equipment. Therefore, the presented case study constituted the occasion to compare a rangebased survey with a fast 3D acquisition and modelling using a Structure from Motion solution. These survey procedures were adopted at an architectural scale, on a single building, that was surveyed both on the outside and on the inside. Assessments on the quality of the rebuilt information is reported, as far as metric accuracy and reliability is concerned, as well as on time consuming and on skills required during each step of the adopted pipelines. For all approaches, these analysis highlighted advantages and disadvantages that allow to conduct evaluations on the possible convenience of adopting range-based technologies instead of a traditional topographic approach or a photogrammetric one instead of a range based one in case of surveys conducted at an architectural/urban scale.

Challenges and Opportunities for the Implementation of H-Bim With Regards to Historical Infrastructures: A Case Study of the Ponte Giorgini in Castiglione Della Pescaia (Grosseto – Italy)

“…In both cases (TLS and SfM), the final output is a point cloud or a 3d mesh model that can be used as tracking reference systems for the definition of parametric elements suitable for the BIM model. The literature shows that improvements in digital photogrammetry that mean that we can consider it a reliable technique in the 3D acquisition field, comparable with results from laser scanners [8][9][10][11][12]. The decision of choosing one of the two techniques before mentioned (TLS of SfM) could be done in relation of the morphology and the accessibly of the area (due to the maneuverability of the tools) but, at the same time, connected on costs evaluation.…”

BIM for heritage science: a review

“…However, the combination of Laser Scanning outputs and Digital Photogrammetry ones can be delicate, as the devices must be both properly calibrated, and error propagation is likely to occur [53]. It is also possible to compose a structure from high-resolution images through Structure from Motion (SfM) [50,55] methodology. SfM is based on the principle that 4 non-coplanar surfaces can be detected by three orthographic projections [55].…”

Virtual and Physical Recomposition of Fragmented Ecclesiastical Frescoes Using a Photogrammetric Approach

“…In the last decade a new surveying methodology based on Structure from Motion (SfM) algorithms has been developed, implemented and applied in the Cultural Heritage field of studies (El-Hakim et al, 2003;Barazzetti et al, 2010;Doneus et al, 2011;Verhoeven et al, 2011;Verhoeven et al, 2012;Lo Brutto et al, 2012;De Reu et al, 2013;Manfredini et al, 2013). Although these procedures may suffer from reduced accuracy when applied to large structures and buildings without the support of a proper topographic survey, they resulted suitable for the purpose of the present study, i.e.…”