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The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B5. Beijing 2008
scanning was performed by each direction and total 35 scanning
data(17 up-lines and 18 down-lines) were scanned as moving in
order for the gap of each scanning data to be about 40m.
Figure 7. Constituent diagram of laser scanning for registration
and georeferencing in the object tunnel.
Figure 9. Panoramic view of a sub-sections
The data obtained in the process of a sub-project included the 3
dimensional location information, RGB information and
reflection powerfulness information and the primitive data of a
sub-project were appeared like Figure 10 and Table 3.
No
X
Y
Z
R
G
B
Intensit
y
1
6.036
3.203
-1.715
158
181
144
25
2
9.522
4.235
-0.915
213
116
253
64
3
11.265
3.563
0.236
161
153
151
30
And the ground reference points were facilitated at the starting
part and the ending to convert the multi scanning data into the
absolute coordinates. 3 round-type targets were facilitated at the
repeated location like Figure8 for the conformation of sequent
multi scanning data and precisely scanned in the process of
each sub project work.
object
a rari 9e
a ran 96
• a location of
© a sohencat target for
Figure 8. Plan view of spherical target arrangement for the
registration of continuous scanning data.
At 2 ground reference points facilitated at each starting point
and ending point, the round-type targets with the high reflection
powerfulness were facilitated and the precise scanning was
performed to achieve the conversion into the absolute
coordinates. The photograph which automatically mosaicked
the snap photographies obtained while the laser scanner was
rounded 360° in the horizontal direction within the concerned
tunnel is like Figure 9.
Table 3. Raw point clouds data including various informations
Figure 10. Illustration of raw point clouds data obtained from a
sub-sections
3.2 Results of measurement
The transmitted data were treated by Real Works Survey
developed by Trimble company. At the step of treatment, the
registration and the geo-referencing were performed and finally
the accuracy of treated data was analyzed. And for the
registration, 3 round-type targets were facilitated at the repeated
locations in the process of the sequent sub-project and precisely
scanned in the process of each sub-project work. The round-
type targets were facilitated like Figure 11 and the figures of the
targets precisely scanned at the sequent prior and post sub-
project are as per Figure 12 and 13.