160
7. CONCLUSIONS.
We have presented the current state of our research in
order to develope a low cost mobile mapping system,
providing sufficient accuracy to perform road surveys
for GIS applications. The lack of the INS has lead us to
implement a georeferencing algorithm by which the
istantaneous position and orientation of the van can be
recovered by the differentially corrected GPS data
only. For the same reason above, we can't get the 3D
coordinates of any object selected on corresponding
images, but rather its 2D coordinates on a projection
map, therefore the object elevation cannot be restituted.
Anyway, the capability to locate on a map any feature
of interest through rapid road survey has represented
our primary goal in developing such a MMS.
At the present we have carried out only separated tests
for the various modules which make up GeoVision, but
we have in plan to assess the performances of the
whole surveying system in real environment, testing it
capabilities for real time data acquisition and the final
accuracy for object position as derived by post-proces
sing step.
Through the contribution provided us by the VRG
(Virtual Reality Group) of NRC Canada, this mobile
mapping system can be integrated with the BIRIS
sensor, in order to detect the road surface deformations.
ACKNOWLEDGMENTS
We acknowledge J. A. Beraldin and F. Blais of VR
Group of NRC Canada, for the use of BIRIS sensor in
road survey applications, and ing. A. Menin of Buil
ding and Transports Department of Padua University,
for the help spent to assemble the system.
This work was developed with the project "Digital
surface modeling by laser scanning and GPS for 3D
city models and digital orthophotos", partly financed
by MURST (Italian Ministry of University and
Research) in 1999 as a project of relevant national
interest. National coordinator: Riccardo Galetto, Head
of the research unit: Antonio Vettore.
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