Proceedings 18 th International Symposium CIPA 2001 
Potsdam (Germany), September 18 - 21, 2001 
THE STATUE OF RAMSETE II - INTEGRATION OF DIGITAL PHOTOGRAMMETRY 
AND LASER SCANNING TECHNIQUE FOR 3D MODELLING 
Andrea Lingua (*), Fulvio Rinaudo (*) 
(*) Politecnico di Torino - Dipartimento di Georisorse e Territorio 
C.so Duca degli Abruzzi, 24 - 10129 TORINO 
Tel. +39-011-5647659/7700 Fax. +39-011-5647699 
Email: rinaudo@polito.it; lingua@polito.it 
KEY WORDS: Laser Scanner, Dense DTM, 3D Modelling, Archaeological Photogrammetry 
ABSTRACT 
The investigation of archaeological and architectural goods can obtain great advantages from the reconstruction of 3D models for 
more effective object analysis and 3D navigation. For this purpose it is necessary to derive a dense digital elevation model (DTM) 
that is useful for 3D modelling. DTM surveying is traditionally performed by means of profiling total stations or derived from photo- 
grammetric stereo-plotting. 
In recent years, laser scanner technology has also been developed for non industrial application and new instruments have been pro 
duced that satisfy the requirements of cultural heritage recording. Thousands of points can be surveyed in a few seconds, with accu 
racies that are adequate for particular applications, to build a dense DTM that is directly compatible with a great number of represen 
tation techniques and which can be integrated with more traditional survey methods. 
A practical example, based on the integration of digital photogrammetry and laser scanning techniques, is shown in this paper: a 
complete test has been carried out on the statue of RAMSETE II which can be found in the Egyptian Museum of Turin (catalogue # 
1380). 
1. INTRODUCTION 
Laser scanner technology has been applied in industrial applications for many years: robot control and the metrical description of sur 
faces are the best known fields where this technique reaches interesting results and high accuracies. 
Laser technology has also offered a considerable contribution to topographical applications allowing the measurement of distances 
without artificial reflective devices. More than ten years ago, AG A and WILD instruments implemented this technology inside total 
stations and electronic theodolites (AGA IMS 1000 total station and WILD DIOR 3002 distance meter). The most recent motorized 
total stations can be seen as the first precursors of modem terrestrial laser scanner devices. 
Laser scanner devices are able to define r, cp, 9 spherical coordinates of angular regularly spaced points, in a local reference system 
defined inside the instrument itself: the angular coordinates are set by the device and the distance is measured by a laser beam. These 
instruments can acquire thousands of points in a few minutes and all the information (spherical coordinates, cartesian coordinates, 
reflectance values) are stored in a PC or directly inside the instrument. 
The density of the surveyed points obviously depends on the distance between the instrument and the object and on the angular steps 
used by the laser scanner device. The acquired data always show non negligible noises that must be removed by means of statistical 
approaches. 
In aerial applications a great deal of effort is required to define the positions of the instrument during the acquisition and the correct 
computation of the coordinates of the surveyed points in a common reference system: this is obtained using GPS and inertial platform 
information.In terrestrial applications, laser scanners are easy to handle instruments. The reference system is stable during the acqui 
sition and defined by the instrument itself. In this case the surveyed points are ready to use immediately after the acquisition phase. 
The operational range of the terrestrial laser scanners allows to measure distances ranging from a few millimetres to some hundreds 
of meters: this fact fits the requirements of all the possible applications that cannot be satisfied when using aerial laser scanners. 
The product of a laser scanner device is a dense and irregular DTM: the limited acquisition times, 
the low prices of the acquisition phase and the large amount of metric information that can be ob 
tained are the most attractive properties. None of the other survey technology (topography, GPS and 
photogrammetry) can reach the same performances in DTM production. 
As far as aerial applications are concerned, 3D city modelling and the automatic production of large 
scale true orthophoto of urban areas are the first practical uses that have been investigated. 
In terrestrial applications the DTM obtained from laser scanner devices can be directly used for the 
3D modelling of quarries and slopes, the rapid and economic acquisition being the most attractive 
qualities for the monitoring of these dynamic phenomena. 
In the field of cultural heritage recording a large number of studies are in progress to test the accu 
racy, the possible integration of the traditional survey techniques and the new possibilities that are 
offered for the metric description and representation of the objects. 
The present paper shows a practical example of integration of the data acquired with a terrestrial la 
ser scanner device used for the digital photogrammetric documentation of the RAMSETE II statue 
(Egyptian Museum of Turin - Italy- catalogue #1380 ). 
After transportation from Egypt to the Egyptian Museum in Turin (the second most important Egyp 
tian museum in the world) the statue (fig. 1) was found to be broken into many blocks that were then 
assembled at the end of the XIX century. The vibrations due to the bombardments during World 
War II and the deterioration of the materials used for the reassembling, have rendered the stability of 
the statue critical. 
Fig. 1: The RAMSETE 
II statue in the Egyptian 
Museum of Turin (Italy)