hul 2004
3D MODELLING OF THE MARKET GATE OF MILETUS
DEVELOPED FROM PHOTOGRAMMETRIC EVALUATIONS
K. Ringle*, M. Nutto T. Voegtle? M. Pfanner^, M. Maischberger^
‘Institute of Photogrammetry and Remote Sensing, University of Karlsruhe, Englerstr. 7,D-76128 Karlsruhe, Germany
(ringle, nutto,voegtle)@ipf.uni-karlsruhe.de
® ARGE Pfanner, Dircksenstr. 46, D-10178 Berlin, Germany , arge@pfanner-baustatik.de
Commission V, WG V/4
KEY WORDS: Photogrammetry, 3D-Visualisation, CAD, Cultural Heritage, Architectural Heritage Conservation, Archeology
ABSTRACT:
After rediscovery in 1903 the impressive Market Gate of Miletus was transported to the Pergamon Museum in Berlin (Germany) in
1907/08. In 1929/30 the object was rebuilt in the original dimensions (about 30m x 16m x 5m). In more than 70 years the monument
had suffered from damages of many kinds. After all, a modern reconfiguration of the Pergamon Museum today requires a complete
photogrammetric documentation as a basis for restoration of the Market Gate of Miletus.
Due to the complexity of damage, mapping a digital 3D model of the market gate, generated from high accurate photogrammetric 3D
data (+/- 5 mm), was necessary to understand the relations between damage and stress analysis more exactly. To obtain this high
accuracy with sufficient economy, data acquisition had to be made with two different camera systems. The front parts were taken by
a UMK 1318 while the interior parts were recorded by a SMK 120 / SMK40. For determination of the necessary 3D information
stereoscopic models had been analysed by an analytical plotter (AP).
Starting from a three dimensional CAD vector model a volume model was developed close to reality. Therefore, comprehensive
rendering methods, effects, texture mappings and animations were used. By means of this 3D model, it is possible to visualize the
single components of the building, e.g. the original and modern parts which had been classified before by restoration experts.
Through this representation, the interior iron construction of the Market Gate of Miletus can be shown. By computer animation
different parts like single columns or architravs can be featured in detail, too.
In future the 3D model will contribute to a spatial information system which will assist restoration activities on the one hand and will
be used for tourist information inside the Pergamon Museum on the other hand.
1. INTRODUCTION outer solid line is the contour line of the exhibition room.
Different grey values represent different depths of the
The monumental Market Gate of Miletus was built between ca. architectural elements (black: front level, dark grey: middle
120 and 130 AD in the time of the roman emperor Hadrian.
Parts of the market gate were rediscovered in 1903 during the
archaeological excavations in Miletus. The gate was rebuilt in
1928/29 inside the new Pergamon Museum in Berlin including
integrations in modern materials replacing the destroyed parts
(Figure 1). Photogrammetric data acquisition was performed by
standard cameras, i.e. UMK 1318 for the front parts and
SMK120 / SMK40 for the interior parts of the gate, e.g. for the
extraction of vertical cross sections, upright projections and
special details. The control points were measured by an
accuracy of approx. rms-t3mm. In order to fulfil the demands
of high accuracy the stereoscopic models were processed at an
analytical plotter DSR-11 (Leica) In model orientation an
accuracy of approx. rms-t5mm could be obtained. The main
contour lines and roughly the main ornaments were mapped. As
an example Figure 2 shows one photogrammetric result in terms
of a front view of the whole market gate including columns (in
this case without flutes) and brickwork of the back plane. The
level, light grey: back plane level). More details about the
Market Gate of Miletus, its acquisition and analysis can be
found in Vógtle et al. (2003). These photogrammetric data are
the basic information for a subsequent 3D modeling process. A
3D respresentation of this complex building was to improve the
possibilities of visualisation and the spatial impression as well
as the evaluation by static experts. For this model it is not
necessary to include the (partly) damaged status of the building
elements but to represent more or less an idealised shapes
reconstructed by means of the real measurements. SolidWorks®
was used for modelling of the market gate. It provides very well
the concept to build up complex structures by combination of
simple basic elements. By this procedure the symmetries of the
building can be utilised. In the following some representative
elements of this reconstruction process will be explained in
more detail.