The role, opportunities and challenges of 3D and geo-ICT in archaeology

Archaeology joins in the trend of three-dimensional (3D) data and geospatial information technology (geo-ICT). Currently, the spatial archaeological data acquired is 3D and mostly used to create realistic visualizations. Geographical information systems (GIS) are used for decades in archaeology. However, the integration of geo-ICT with 3D data still poses some problems. Therefore, this paper clarifies the current role of 3D, and the opportunities and challenges for 3D and geo-ICT in the domain of archaeology. The paper is concluded with a proposal to integrate both trends and tackle the outlined challenges. To provide a clear illustration of the current practices and the advantages and difficulties of 3D and geo-ICT in the specific case of archaeology, a limited case study is presented of two structures in the Altay Mountains

Determining geometric primitives for a 3D GIS : easy as 1D, 2D, 3D?

Acquisition techniques such as photo modelling, using SfM-MVS algorithms, are being applied increasingly in several fields of research and render highly realistic and accurate 3D models. Nowadays, these 3D models are mainly deployed for documentation purposes. As these data generally encompass spatial data, the development of a 3D GIS would allow researchers to use these 3D models to their full extent. Such a GIS would allow a more elaborate analysis of these 3D models and thus support the comprehension of the objects that the features in the model represent. One of the first issues that has to be tackled in order to make the resulting 3D models compatible for implementation in a 3D GIS is the choice of a certain geometric primitive to spatially represent the input data. The chosen geometric primitive will not only influence the visualisation of the data, but also the way in which the data can be stored, exchanged, manipulated, queried and understood. Geometric primitives can be one-, two- and three-dimensional. By adding an extra dimension, the complexity of the data increases, but the user is allowed to understand the original situation more intuitively. This research paper tries to give an initial analysis of 1D, 2D and 3D primitives in the framework of the integration of SfM-MVS based 3D models in a 3D GIS

Spatiotemporal data as the foundation of an archaeological stratigraphy extraction and management system

A

Helium balloons for 3D modelling : off to a flying start?

Currently, the use of unmanned aerial vehicles (UAV) as a platform for aerial photography is becoming more and more common practice for 3D photo modelling applications. However, the use of these platforms has several drawbacks. Firstly, to recharge the UAV’s batteries a nearby electricity source is needed. This might cause problems when performing research in remote areas. Secondly, a skilled operator is required to control the UAV. Thirdly, there might be legal restrictions to the use of such an aerial platform in several countries. Finally, purchasing a UAV can form a big cost when performing a small project. To address these issues, the use of helium balloons as an alternative and low cost platform for aerial photography is proposed. To assess its efficiency, effectiveness and accuracy, several case studies are elaborated. In the first case study the accuracy of a 3D model created by laser scanning is compared with a 3D model created by helium balloon imagery (Ghent, Belgium). The second case study comprises a test of the performance of the system used at the lake of Vassivière (France). Finally, the helium balloons are deployed on the archaeological site of Edzna (Mexico). Here, a comparison is made between the accuracy of 3D models generated by UAV and helium balloon imagery. In conclusion, the advantages and drawbacks of the use of helium balloons as platform for aerial photography are listed. This allows potential users to make an informed choice between this and other platforms

On the way to a 4D archaeological GIS: state of the art, future directions and need for standardization

In recent years, Geographical Information Systems (GIS) have become a wide-spread and increasingly used technology in various domains. GIS have proven their strength in archaeological research applications, such as the analysis of spatial relations between excavation objects and predictive modeling. Besides the increasing attention to GIS, in diverse research areas much interest has aroused to explore the potentials of three and even four dimensionality (3D/4D). In cultural heritage, this has mainly resulted in a proliferation of 3D digital visualizations, predominantly virtual reality models. Notwithstanding their impressive appearance and great value for publication purposes, the analysis and data exchange capabilities are generally abandoned. Integrating these two research trends will bring benefits to a wide range of domains. Although a 4D GIS would facilitate better insights and more complex analyses, in archaeology, realizing this combination is challenged by the diversity of archaeological data and its inherent complexity. Fully exhausting the power of GIS is currently improbable because archaeological data are more complex than most of the regular geospatial data. Therefore, a specifically to archaeology tailored 4D GIS based on a customized data model proves to be necessary. This paper first tries to present the state-of-the-art of current 4D data modeling in archaeology. Second, points of attention for future research directions are geared to this overview. Accordingly, integrating an object-oriented and event-driven approach is brought forward to take into consideration