Technical Design Report Super Fragment Separator

DRAFT
mated guided vehicle system. Via tracks this device will be driven along the beamline in the activated
area, which has to be surveyed. Appropriate fiducial points are mounted on the magnets /
cryostats. In addition, photogrammetric tie-points and calibrated scale-bars are distributed in object
space to guarantee a stable photogrammetric network. At least two adjacent components are captured
in one shot, before the vehicle starts to move to the next stop for taking the following picture.
After finishing data acquisition the camera system is lead out to a radiation-protected storage room
to download the image data. A bundle adjustment provides correction values for the alignment of
the accelerator components that is completed by remotely controlled adjustment devices. Another
camera run is performed to check the quality of remote alignment [101].
Figure 2.4.147: Schematic view of a possible configuration in an accelerator tunnel. The camera vehicle
(green) carries two divergent digital cameras. By moving the vehicle along the tunnel (red arrows), any part
of the magnets will be captured by two or more images. This results in an image bundle for the whole tunnel
to be processed in a photogrammetric bundle adjustment.
Different digital cameras for industrial application have been tested at a photogrammetric test field,
in order to analyze their geometric stability and the accuracy of image measurement. In the context
of possible camera damages during operating time of RALF by remaining radiation after machine-shutdown,
some experimental tests were performed at ambient conditions of gamma dose
rates of up to 10 mSv/h, which can be expected at PF2 (pre-separator focus point 2 of Super-FRS).
Although image analysis tools detected a slight influence, the tests showed no significant loss of
image point accuracy.
Considerations to a photogrammetric network design, regarding stretched objects, have been carried
out; extensive simulations were computed, which resulted in satisfactory, homogeneous object
point accuracies in 3D (approx. 0,1 to 0,2 mm) [102].
Aspects of image analysis, camera vehicle and motion system, data transfer and power supply as
well as adjustment devices appropriate to the environmental conditions were investigated. Fiducials
of later on strongly shielded magnets and a measuring method to connect precisely the adjacent,
accessible sections to the inaccessible areas were studied.
In order to verify the simulations, to test cameras, to try different types of targets and image
analysis and to investigate the influence of different configurations of the bundle adjustment a test
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