3D Laserscanning for
Engineering and Architectural Heritage Conservation
Mettenleiter, M.; Härtl, F.; Heinz, L; Neumann, B.; Hildebrand, A.; Abmayr, T.; Fröhlich, C.
Zoller + Fröhlich (Z+F) GmbH, Simoniusstr. 22, D-88239 Wangen, Germany
Phone: +49-7522-9308-0; www.zf-laser.com; info@zf-laser.com
KEY WORDS: Architectural Heritage Conservation, Engineering Heritage Conservation, Close
Range Photogrammetry and 3D Scanning, Cultural Heritage, Industry, Laser scanning, Terrestrial,
Three-dimensional
ABSTRACT:
Laserscanners are used more and more as surveying instruments for various applications. With the
advance of high precision systems, capable of working in most real world environments under a
variety of conditions, numerous applications have opened up. The developed IMAGER 5003 is a
state-of-the-art, high precision, high speed laser scanner that provides accurate measurements.
In order to monitor scenes by means of range and reflectance images, the IMAGER 5003 is based
on a phase-shift measurement principle. In combination with a newly developed and patented
scanning system, the system provides a wide field of view of 360° (horizontal) x 310° (vertical)
with an image resolution of up to 36,000 x 20,000 pixels within one single image. Scanning time
for a full scan depends on the section to be scanned and the number of measured points - for a
standard image 360° x 310°, 8,000 x 8,000 pixels less than minutes. The IMAGER 5003 measures
both, range and reflectance images at the same time. The range image generates geometric
dimensions of the environmental scenes whereas the reflectance image generates a photographic
like impression of the scanned environment which is used for feature extraction, visual inspection,
object identification, surface classification and documentation purposes.
To realise surveying tasks in architectural, archaeological and cultural landscapes conservation, the
point clouds measured by the laser radar are combined with a specially developed colour camera
providing a panoramic image of the 3D environment. The camera is developed by the DLR and
provides a good resolution so that images can be mapped onto the point clouds of the IMAGER.
This paper reports design and applications of the Z+F IMAGER 5003 and the DLR panoramic
camera. It focuses on accuracy of the system and reports the realised approach from physical
measurement of point clouds to coloured point clouds in the end. It shows results from two cultural
landscape conservation projects - one inside and one outside measurement - and gives an outlook
to further work in the laser scanning development area.
1. INTRODUCTION
1.1 Laser scanner for surveying
The visual laser scanner IMAGER 5003 of Z+F
(Fig.l) is an optical measuring system based on
the transmission of laser light. The environment
is illuminated on a point by point basis and then
the light reflected by an object is detected. The
laser scanner consists of a one-dimensional
measuring system in combination with a
mechanical beam-deflection system for spatial
survey of the surroundings.
The laser scanner is designed for non-tactile,
high performance measurements with high
robustness and accuracy. This is necessary for
exploration by surveying industrial plants and
production halls, as long down-times in
production have to be avoided; but it is also
required for cultural sites like churches or
