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4.4 Us e of the AP/C as digital plotting device 
Much has been said in favour of digital terrain model data 
acquisition. As compared to standard plotters requiring costly 
magnetic tape and coding additions the analytical plotter possesses 
all ingredients to act as a digital data acquisition device. 
With it heights of points may be recorded at irregular intervals 
(as in tacheometry) or at regular grid points. Profiles may be recorded 
at regular distance or time intervals. Contours may be digitally 
coded as well as break lines. 
With respect to position, coded points or lines may be acquired for a 
planiinetric digital terrain model. 
At the T.U. Hannover the following programs have been or are being 
prepared in this context: 
1. The recording of point coordinates x y z on disk, 
2. the driving of the plotter to point grid positions, where 
the operator sets z by the hand wheel and recordsx y z, 
3. continuous profile scanning in or recording mode, 
4. recording of contours in At or As mode, 
5. recording of coded break lines, 
6. recording of point objects with code in x y z, 
7. driving the plotter to ground coordinate positions, 
8. recording of coded lines. 
to 
The programs will permit/evaluate the techniques of digital terrain 
data acquisition varying acquisition conditions (spacing, mode, 
speed) by existing DTM programs (Kraus, Koch, Swedish highway 
administration, Hansa Luftbild Geomess).