The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part Bl. Beijing 2008 
1184 
Figure2. picture of helium airship 
Figure 2 shows the helium airship for low altitude 
photogrammetric mapping. 
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3. SENSOR SYSTEM 
A super-wide-angle camera is constructed by four digital 
cameras, mounted in different optical axis directions. The four 
images taking from different cameras are special designed to 
have some overlapping areas, which used for high accuracy 
calibration of relative orientation elements between the four 
cameras to make compensation for the deformed errors due to 
the light and simple constructed mechanical frame. The 
geometric optical distortions from each camera are accurately 
calibrated. The advantages in using super-wide-angle cameral 
are as follows: 1) to get large framed images at very low 
altitude flying for rising the production efficiency, 2) to enlarge 
the base to height difference at terrain. 
Due to the limited efficient load of UAV platform and in order 
to keep the system to be easy, only general purpose digital 
cameral are accepted and the installed stabilization plant are in 
low accuracy, but due to the possibility of very low altitude 
flying of UAV, this photograph system can acquire very high 
resolution images. To sum up the advantages and disadvantages 
of UAV data acquisition system, the UAV images are suitable 
for large scale mapping and routine monitoring. 
Figure 6a, b show the super-wide-angle camera constructed by 
four digital cameras. 
Figure3. flying control system and equipments 
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Figure4. remote grand station and equipment 
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Figure5. data communication and monitoring system 
Figure 3, 4 and 5 show the flying control, data communication 
and grand monitoring equipments, same for the both platforms. 
Figure6. a, b the appearance and inside of super-wide-angle 
camera 
Figure 7 shows the overlapping structure of the images 
projected from the four camera data. 
Figure7. overlapping structure of the images projected from the 
four cameras 
In figure 7, point i =1, 2 ... 12 are selected for high accuracy 
calibration of relative orientation elements between camera A, 
B, C, D. The mathematical formulas have been derived as 
following. 
Length 
12—20m 
Speed 
0~50km/h 
Diameter 
2~4m 
Height of aviation 
50m ~ 1000m 
Task Load 
5~50kg 
Radius of Control 
10km 
Aviation Time 
3—5h 
Control 
Program-controlled, 
remote-controlled,