The Accuracy of Digital Models for Road Design - Geoinformatics for Intelligent Transportation - page 236

Fig. 1 Data sample of the
aerial laser scanning — source
material for re-laying the R55
road (Courtesy of GEODIS
BRNO Ltd)

usually consisting of two integrated units: scanning and navigational. Due to
high density, speed and above all the spatial accuracy of obtained point clouds,
the method represents one of the most effective methods of obtaining spatial
information for precise designing works. By selecting a suitable measurement
method, using appropriate vehicles (eventually utilizing terrain three-wheelers
or manual walk-survey under hard inaccessible terrain conditions with an
apparatus in bag) and subsequent elaboration we can reach results, which we
could not reach by other methods. During post-processing, we can use addi-
tional information received during scanning each point, especially the
sequence of reflections and reflective intensity. The cleared data can serve for
generating detailed digital models, depicting cross and longitudinal sections in
any position and make other elevation analysis. Such data with RMSW
h = 0.015 m

see [ 4 ], represent the most accurate source material for
designing works. Currently there are various SW platforms, which are ready to
work with these data and also enable the 3D designing. In comparison with
conventional methods, this one brings relatively high time savings during the
designing works and above all

—

the savings during the construction itself

(Fig. 2 ).

Fig. 2 Sample of detailed 3D
digital model of a current road
(Courtesy GEOVAP
Pardubice Ltd)