International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B3. Istanbul 2004
Horizontal cross sections with 1-meter interval were computed
from the 3D surface model. The cross sections surface
representation is simpler to manage and render with standard
CAD software.
dome
ew of the 3D surface model (detail).
Figure 1. Perspective vi
Figure 2. Photograph of the tunnel in Fig. 6.
As an attempt to evaluate the quality of the model, the points
from the local network were compared with the model. Only 6
of the 13 points fell inside this study area. They are too few
points to consider the results significative and they are also
poorly distributed: Points 4000-4002 are very close one of each
other.
KnownH Laser H AH
Number Easting Northing
2001 431226.611 4691455.977 1501.910 1500.986 -0.924
2002 431239.628 4691461.193 1499.961 1494.111 -5.850
4000 431555.676 4690889.853 1458.325 1458.053 -0.272
4001 431567.400 4690893.977 1459.470 1459.192 -0.278
4002 . 431572.284 4690888.450 1460.905 1460.510 -0.395
6000 | 431522.593 4690889.032 1506.640 1506.695 40.055
Table 2. Differences between final DTM and GPS network points
Point 2002 was measured on a bridge and in the model this
construction was removed. Without considering point 2002 the
statistics of the results are:
Number of points: 4
Average of the errors: -0.223 m
Standard deviation: 0.193 m
RMS: 0.270 m
An independent survey to evaluate the quality of the model is
pending at the time of writing this paper.
REFERENCES
Alamüs, R., Bosch, E., Serra, A., Pla, M., Talaya, J., Miranda,
J., 2004. On the accuray and performance of the Geomobil
system. IAPRS. Istambul, Turkey. Vol. XXX.
Baltsavias, E., 1999. Airborne laser scanning: basic relations
and formulas. ISPRS J. Photogramm. Remote Sensing, 54; 199-
214.
Kornus, W., Ruiz, A., 2003. "Strip Adjustment of LIDAR
Data”. WG III/3 workshop on airborne laserscanning, “3-D
reconstruction from airborne laserscanner and InSAR data",
8.10.03 - 10.10.03, Dresden.
Ruiz, A., Kornus, W., 2003. "Experiencias y aplicaciones del
LIDAR”. V Semana Geomatica, 11.2.03 -14.2.03, Barcelona.
Serra, J., 1982. Image Analysis and Mathematical
Morphology. Academic Press, London, 1982
Talaya, J., Bosch, E., Alamus, R., Serra, A., Barón. A., 2004a.
GEOMOBIL: the Mobile Mapping System from the ICC. 4th
International Symposium on Mobile Mapping Technology
(MMT'2004). Kinming, China.
Talaya, J., Alamüs, R., Bosch, E. Kornus, W.. 2004b.
Integration of a Terrestrial Laser Scanner with GPS/IMU
Orientation Sensors. Istambul, Turkey. Vol. XXX, Part B3.
TerraSolid, 2004a. TerraScan User's Manual.
TerraSolid, 2004b. TerraModeler User's Manual.
Vosselman, G., 2000: “Slope based filtering of laser altimetry
data". IAPRS, Vol XXXIIL Part B3, pages 935-942.
Amsterdam, The Netherlands.
ACKNOWLEDGEMENTS
Many people has been involved in this project. We want to
acknowledge especially the help from the company Santiago &
Cintra and the work done by Ernest Bosch, Miquel Soro, Marta
Sastre, Miriam Moysset, Santi Sánchez and Jordi Hernández.
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