We have developed a software system for evaluating the merits of
several virtual environments for archaeological tasks. The ARCHAVE
system, developed at the SHAPE lab at Brown University, presents
archaeological excavation data and site information via a virtual
reality interface. These data come from the Brown University Great
Temple excavations in Petra, Jordan [1].

As Bowman proposes [2], we are designing several user studies that utilize the following
virtual environments: a Cave, Barco Baron table, head-mounted
display and the desktop, to evaluate the hypothesis
that virtual reality is useful for this kind of research. This type of study is one of the
``Hot open challenges'' in VR research [3].

Following standard archaeological practice,
artifacts recovered from the excavation site are recorded with precise
three-dimensional characteristics. The database for the Great Temple
excavation contains more than 115,000 artifacts, recorded since
1993. Unfortunately, the full potential of archaeological databases is
rarely realized. Most archaeologists are not able to analyze the geometric
characteristics of artifacts and their spatial relationships with other
elements of the site [4].

For analysis, it is essential to maintain the artifacts in their
architectural and topographical context. Following what Forte proposes
in [5], we believe that a virtual environment will be particularly useful
in helping researchers understand their data to develop new conclusions and
hypotheses about the history and evolution of Nabataean culture.

The ARCHAVE system displays all the components of the archaeological
excavation in the context of an architectural reconstruction of the temple.

The virtual site is divided into a grid of trenches where the
dirt is excavated and important objects recovered and analyzed. Each
trench is organized into layers, and artifacts are plotted in their
exact find locations.

As the user enters the site, different artifacts can be interactively
retrieved from the database and viewed, together or separately, for
spatial analysis. For example, a user can bring up pottery finds and
coin concentration data to explore the relationship between the two.

In a fully developed environment, a researcher will be able to study
the site by navigating through different stages of the excavation or
important historical phases of the building. He or she will also query
the database of artifacts using speech recognition, gesture-based
commands, or automatic query generation depending upon the state of
the user in the virtual site.

This application will help us answer the following specific
questions: What virtual reality environment, if any, performs better
in giving archaeologists the adequate interface and contextual
information they need for analysis?  What context is necessary for
performing archaeological tasks?  Which interaction techniques allow
the user to navigate through an archaeological site and access a
database of artifact information?  How do we display the results of
those queries in a way that he or she can gain maximum insight about
the data?

From a number of informal tests and demonstrations, we have observed
that users get a good sense of immersion, and those who have visited
Petra report that using the system is similar to being at the actual
site.  We have also observed that, because the temple is large, users
need to look up to see important parts.  In our Cave this is
problematic because the ceiling is not a display surface.  One of the
main problems we have detected is that scale is hard to convey
accurately.  We are currently developing a pilot user study to compare
how important this factor is in the different platforms and how it
affects the archaeologists studying the site.

The system we have described allows archaeologists to preserve and visualize
the data they collect in a 3D environment.  It enables them to better understand
the context of the excavation data and gain freedom of movement through the
dataset (i.e., site, trenches, trench layers, architecture and artifacts). It is also
significant because it allows the user to easily manipulate objects and variables
and query information for analysis.

References

[1] Joukowsky, Martha S.,
Petra Great Temple: Volume I: Brown University Excavations 1993-1997,
E.A. Johnson Company, USA. 1998.

[2] Bowman, Doug A.,
Interaction Techniques for Common Tasks in Immersive Virtual Environments -
Design, Evaluation and Application,
PhD Dissertation, Georgia Tech., 1999.

[3] Brooks, Frederic P.,
What's Real About Virtual Reality,
IEEE CG&A, December 1999, 16-27.

[4] Crescioli, M. and Niccolucci, F.,
P.E.T.R.A.-Data: an Integrated Environment for Archaeological Data Processing,
New Techniques for Old Times: Computer Applications and Quantitative Methods in Archaeology,
Proceedings of the 26th Conference,
Barcelona, March 1998. BAR International Series 757, 133-134.

[5] Forte, Maurizio,
About Virtual Archaeology: Disorders, Cognitive Interactions and Virtuality,
BAR International Series 843, Archaeopress, England, 2000, 247-259.